An update

For those of you who've been wondering where I've been, my family has been a little busy with the recent birth of our daughter. Please be patient! I will start posting entries again in the near future.

More than just bed-head: UHS

I came across an article on a news website today that I read and thought, "this has got to be a joke." The article was entitled "The tangled truth about uncombable hair," and it began with the following sentence:
"If ever there were a disease designed to vex a mother, it’s uncombable hair syndrome (UHS)."

You're joking, right? Uncombable Hair Syndrome? They came up with a disease name for when someone has messy hair? As I read on, I became more disbelieving; my disbelief was not helped by the statement that it was first described 35 years ago in a French medical study, which called it "cheveux incoiffables." Okay, now I know you're pulling my leg, right?

Actually, much to my surprise, no! This story is legit. This syndrome is legit. It may sound wacky, but it's for real. Some people have messy hair. Some people have hair that is easily tangled. Some people have truly horrible cases of bed-head when they get up in the morning. But others have truly uncontrollable hair.

Uncombable Hair Syndrome is also known as Pili trianguli at canaliculi, or Spun Glass Hair. This syndrome can manifest itself in children anytime between the ages of 3 months and 12 years old. While these kids start out with hair that looks thin and glassy (though still relatively normal), the hair begins to become drier, curlier and lighter in color. Eventually, it stands straight out from the scalp and is literally impossible to comb flat.

The reason for this disorder lies in an abnormality in the hair shafts of the affected individual. When examined under high magnification, these hair shafts have 2 unique qualities. First, their cross-section is shaped like a kidney bean (instead of a circle). And second, there is a deep groove or canal that runs down the entire length of the hair. This makes the hair unable to bend like normal hair without such a groove. So it stands straight out from the scalp. But here's the good news. Kids with UHS usually outgrow it. So while their hair may be unmanageable now, it'll get better as they get older.

But in case you're wondering whether your messy hairdo could be the result of UHS, the odds are quite strong that it's not - UHS is an incredible rare syndrome. In the last 35 years, barely 100 cases have been reported in the medical literature.

It's far more likely that you just have easily tangled hair.

In honor of the start of school

I thought I’d write an entry in honor of all of the children, teachers and administrators in our country who are just starting up another year of school. The start of the school year brings lots of exciting opportunities, does it not? New books, new subjects, new friends, new challenges – oh, and of course, the possibility of new illnesses. Sometimes school seems the perfect place for the propagation of viruses, bacteria and other assorted bugs. And it’s one of these bugs I want to discuss today – the ever-popular, ever-fun, and ever-exciting pediculosis. Otherwise known as head lice.

What are head lice? A head louse (singular, as opposed to the plural form lice) is a small, wingless insect that lives among human hairs and feeds off small amounts of human blood. How small are they? Lice go through three stages during their life cycle. They start out as eggs, otherwise known as nits. These are very small, about the size of a flake of dandruff. About 7 days after the nits are laid by a female, the lice hatch into the nymph stage. Nymphs look like adult lice, but they’re much smaller. At this point, they need human blood to survive to adult. If they feed enough, after about 7 days as a nymph, they will mature into adult lice, capable of laying their own nits. Adult head lice are tan to grayish-white and about the size of a sesame seed, easily visible to the naked eye; so if you’re going to spot an infestation, it’s the adults you want to be on the lookout for. And adult louse can survive for around 30 days as long as it keeps feeding; if it falls off its human’s head, however, it will die within about 2 days.

Here’s a few facts about head lice that I did not know before I started looking into them:
Head lice cannot survive on any animal besides a human. That means you cannot catch head lice from your pets – cat or dog blood will not sustain a louse.
Head lice cannot jump or fly from head to head. The only way to pass head lice among people is for them to come into direct contact with hair that has a nymph or an adult louse clinging to it. Once that contact is made, the louse can transfer itself to the new person’s head and begin feeding.
Head lice have very strong claws that allow them to hang on very tightly to a strand of hair.
Dessicated head lice and head lice nits have been found on the hair and scalps of Egyptian mummies.
It is believed that 1 in 10 kids in America will come down with head lice at some point during their lives.

Okay, now that I’ve given myself the creeps over imagining all these little bugs crawling over my scalp…

An update from MESSENGER

In February of this year, I wrote an entry about the MESSENGER spacecraft, NASA's recent expedition aimed at learning more about the planet Mercury. Despite being relatively close to us in the solar system (a few scant planets away), we know relatively little about this rocky planet. MESSENGER is an attempt to answer some long-standing questions about the planet, including (if you remember from my previous post) what half of the planet even looks like! I figured it was about time to give you an update on what MESSENGER's been up recently.

Some of the latest news to come from the MESSENGER mission concerns the origin of Mercury's magnetic field. The question of what exactly is a magnetic field opens the door to a big area of physics called electricity and magnetism. I'm not going to go into a lot of detail about magnetism - at least, not right now. I will tell you that a magnetic field is a a field that permeates space and exerts a magnetic force on moving electrical charges and magnets (otherwise known as magnetic dipoles). Earth (as I'm sure you know) has a magnetic field; this fact gives us north and south. There does not appear to be a simple answer for why Earth has a magnetic field. It seems that it has something to do with our rotation. We believe this because the planet Venus, though it has a similar iron core to Earth's, has a different rotation pattern and has no magnetic field itself. Earth's rotation may generate something called a dynamo effect, causing the fluid iron in the core of our planet to circulate. At the same time, convection occurs, drawing the hottest part of the molten iron away from the center of the planet towards the surface. This combination of rotation and convection generates electric currents, which in turn generates and sustains our magnetic field.

Now, while it's long been known that Mercury has a magnetic field (though it is about 100 times weaker than our own), why it does so has been a mystery. Scientists had believed that Mercury's iron core was thought to have cooled long ago; a lack of fluidity in the core would make it incapable of generating a dynamo effect. But it turns out that Mercury's core is not as quiet as they once believed. The latest news from MESSENGER seems to indicate that a combination of volcanic activity and fluidity in Mercury's core is responsible for the generation of this magnetic field.

Of course, as is always the case in science, as soon as one question is answered, another is posed. The question now is not "why does Mercury have a magnetic field," but "why is Mercury's core still molten?" For the answer to that one, however, it looks like we'll have to wait for more data from MESSENGER, and another announcement from NASA.

In the meantime, here are a few other facts about Mercury that NASA has announced from the latest data from the spacecraft:
1. Mercury appears to have active volcanic vents around something called the Caloris basin, This is one of the solar system's largest and youngest impact basin - a basin formed by an impact with an asteroid or comet during the first billion years in the history of the solar system.
2. The planet has shrunk in on itself more than anyone had ever expected - in fact, the planet seems to have shrunk one-third more than anyone predicted
3. The magnetosphere around Mercury is more complex than scientists had predicted. The magnetosphere (a kind of bubble around the planet that contains atomic and molecular particles) contains more complex particles than had been expected, given how close it is to the sun. In fact, many of the particles themselves originate from the planet, and are not carried there by solar wind.

MESSENGER is supposed to make another flyby of the planet in October, so I'm sure that more news about Mercury will be coming shortly. Until then, if you want to see a really interesting picture from the latest set of data, check out picture of the Caloris basin on the MESSENGER website at:
http://messenger.jhuapl.edu/gallery/sciencePhotos/image.php?gallery_id=2&image_id=193

Octopus - up close and personal

I wanted to write a quick post about a topic I've written on before - octopus. In May, I wrote an entry about the intelligence of octopus (and I don't know about you, but some of what I learned certainly surprised me!). Well, my husband and I recently came home from a vacation in Hawaii. We both love to snorkel and scuba dive, and though we weren't able to do any scuba diving this trip, we did get in some great snorkeling. And this time we saw something we've never seen before while in the ocean - an octopus.

Now, we strongly suspect that there are octopus all over the areas where we often snorkel. The rocks and coral have so many cracks and fissures that there are ample hiding places for them. There are also significant numbers of moray eels in the area, and octopus are a tasty snack for a moray (if it can catch one, that is). And finally, we've heard other people say they've seen octopus around there before. So we knew that they were there. But we've never seen one before.

I think there are 2 main reasons for this. First, octopus are nocturnal, and we always snorkel during the day. And second, octopus are really, really, really good at hiding - especially when it comes to camouflage! An octopus sitting motionless in a crevice looks just like a rock - brown and bumpy. Put that "rock" 10 feet below the surface of the water, and a snorkeler swimming over the top of it will never see it.

However, this year we were extremely fortunate. We managed to see an octopus as it was moving to a new hidey-hole. It was fairly easy to see it when it was in motion; moreover, once it was settled into its new spot, we knew where to look for it, and were able to watch it quite easily. It was pretty big, maybe 2 feet long from the head to the tips of the arms, much longer than I ever expected to see in the wild. And perhaps the coolest thing about it was the way that it would rapidly change colors when one of us swam close to it. It would instantly switch from rock-brown to dark red, then fade back to brown when we backed off. I think that means we were spooking it a little bit!

We saw quite a few other interesting sea creatures while snorkeling this year, as well, including both the largest and the smallest moray eels we've ever seen (the largest being probably close to 4 feet long, and the smallest being only several inches), and a huge devil scorpionfish. This has to be one of the uglier fish I've ever seen. They sit on the bottom of the ocean, disguising themselves as rocks. They kind of look like a fishy equivalent of a gargoyle, actually - lumpy, brown, and extremely grumpy looking. And while you don't want to touch these guys (yes, they are poisonous), being able to find one is actually quite a treat. (Can you see the face of this one on the right-hand side of the picture, with a fin in the bottom left corner?)

I'm sure there were all kinds of interesting creatures in the ocean where we were snorkeling that we never even saw. But I think we were very fortunate to find the things that we did! Of course, the next time we go, I'll be on the lookout for even bigger and better things.

All about popcorn

Did you know that popcorn is made from a special kind of corn? I had never really thought about it before, but if asked, I would have guessed that you could use any old corn to make popcorn. All you have to do is dry some kernels, then heat them up and they'll pop, correct?

Actually, no, it turns out that popcorn is a little more sophisticated than that. In researching how it's more sophisticated, I've learned some things about corn that I never knew before.

All corn is a type of maize, of which there are 6 kinds - pod, sweet, flour, dent, flint and pop. The kernels of all kinds of corn are made of 3 things - the germ, the endosperm and the pericarp. The germ is the only living part of the kernel. It's right in the middle of the kernel, and contains the information necessary for that kernel to produce a whole new corn plant (genetic material, enzymes, vitamins and minerals). It's also the part of the kernel that produces corn oil - about 25% of the germ consists of corn oil. The endosperm is the largest part of the kernel. It accounts for over 80% of the kernel's dry weight, and consists largely of starch. The endosperm lies between the germ and the pericarp, or outer hull. The pericarp is very tough, and is designed to prevent moisture loss from the inside of the kernel, as well as protecting the delicate germ from being eaten by bugs or microbes.

Different kinds of corn differ in how much of these 3 components the kernels have, as well as their starch and oil composition. Dent corn, for example (the leading type of corn grown on US farms), has an endosperm consisting of horny starch on the sides and soft starch on the top. As the kernels age, the soft starch shrinks, making a characteristic "dent" in the top of the kernel. Flint corn has no soft starch at the top of the endosperm, so it does not make a dent as it matures. The endosperm of flour corn consists mainly of soft starch, which makes it very easy to grind into flour. Sweet corn, grown for human consumption, has much less starch than any other kind. That's because the sugar in the kernels is not converted into starch in the endosperm - hence the sweet nature of the food. Pod corn is a very pretty kind of corn, with kernels that often turn a variety of colors. It is not eaten very often, but instead is grown to use for decorative purposes. And then, of course, there is popcorn.



Popcorn is specifically - and scientifically - known as Zea mays everta. It is a derivative of flint corn, and is distinctive in that it has a very thick pericarp. The thickness of its pericarp allows for the popping process to occur. When the water inside the germ is heated, it turns into steam. The thick pericarp holds the steam in, where it begins to gelatinize the internal starch and protein in the endosperm. Once the pressure of the steam gets too great, the pericarp bursts, releasing the starch protein and steam in a big pop. As the starch expands, it cools and solidifies into its distinctive popcorn shape.

There are several variables that go into how well popcorn will pop. One important factor is how quickly the popcorn is heated. The internal temperature has to reach about 180 degrees celsius (356 degrees fahernheit) before it will burst. If the kernel is heated too quickly, the external portion of the endosperm will release steam too quickly, bursting the pericarp before the internal part cooks properly. If it is heated too slowly, the building steam may leak out of the tip of the kernel, and it won't pop at all. Popping quality also depends on how much moisture the kernel contains. If there is a lot of moisture in the kernel, it will pop into chewy, soggy pieces of popcorn. Also, very moist kernels of popcorn tend to go moldy easily. If the kernel is too dry, however, it will not produce enough steam to pop well. So popcorn growers usually carefully control the moisture level of their popcorn kernels, and try to dry them out to around 15% of the total kernel weight being moisture.

There are lots of other interesting facts about popcorn that I came across when writing this entry. Here are a few of my favorites:


1. Popcorn usually pops in one of 2 shapes - mushroom (on the left) or snowflake (on the right). Different kinds of popcorn can produce exclusively one shape or the other, or a mix of the 2. Snowflake popcorn is usually used for eating straight as popcorn, which mushroom popcorn is usually used for popcorn confections (like caramel corn).

2. Popcorn kernels can move a distance of up to 3 feet when they burst.


3. "Popability" refers to how many kernels of a given batch of popcorn will pop. Some kernels simply do not pop, and are known in the popcorn industry as "old maids." They are assumed to either by too dry to produce enough steam, or have too leaky a pericarp.


4. Popcorn is the official state snack food of Illinois - which, by the way, produces a lot of the US supply of popcorn.


5. Scientists have found popcorn kernels over 1000 years old in tombs in both Peru and southwestern Utah.



Personally, I really enjoy eating popcorn. And I'm not alone. Apparently, Americans consume an average of somewhere around 17 billion quarts of the stuff per year. That's a lot of popcorn!

Sitting in the catbird seat

I was in the car this morning, and one of my favorite programs on NPR came on the radio. It's a short little thing, usually just 2 or 3 minutes long, but it's always so interesting! The program is called "Bird Note," and every episode describes something about birds. Wild or tame, big or small, common or rare, showy or drab - it runs the gamut. The narrator sometimes talks about the behaviour of the birds, or their environment, or their plumage. One particularly interesting one a few weeks ago compared how much effort it would be for a human to build a nest comparable to that made by a robin. (It would actually be really, really difficult!) Today's show was about a bird called a catbird. Actually, it was about an idiom in which the catbird features prominently - as you might have guessed from the title, the idiom is "sitting in the catbird seat."

I'd never heard this phrase before, but the narrator explained that this phrase means having an enviable position, the upper hand, or the greater advantage in a situation. And the reason it means this is perfectly explained by the behavior of the catbird.

Catbirds are American birds of the mimid family. "Mimid" is Latin for "mimic," and mimids are known for the vocalization abilities. Other mimids include thrashers, mockingbirds and tremblers. The catbird's standard call sounds roughly like a yowling cat, actually, though it can also imitate other birds. (It's alarm or warning call sounds startlingly similar to a male mallard.) There are two kinds of North American catbirds. The grey catbird is the most common, and is found across the US in all kinds of environments (rural, suburban and urban). They are medium-sized and dark in color, with the only notable coloration being a rust-colored patch under their tails. The other kind of catbird is the black catbird, which is found more in Central America and Mexico.

So what does the catbird do to deserve having an entire idiom phrased after it? The catbird (like many animals) relies on height to assert superiority or dominance. If a catbird feels threatened, it will go to the highest position it can find to call out its warning call. The higher that position, the more likely the intruder will back off. In addition, if two male catbirds are jockeying to be the top male in the area (and thus attract the best female), they will take gradually higher and higher perches, trying to outsing the other, until one is at the highest point. The bird who gets the highest is the winner. And, of course, the high perch from which he claims his victory is called "the catbird seat."

So there you go. Sitting in the catbird seat means getting the most advantageous position.

I love finding examples of how something science-related has worked its way into everyday life and language. Okay, so maybe this phrase isn't the most common, everyday phrase you'll ever hear. But now, if you ever do hear it again, not only will you know what it means, you'll also know where it comes from!

Anyone have any other suggestions for phrases or idioms that have their origins in science?

The science of fireworks

In recognition of the fact that tomorrow is the 4th of July, I'd like to spend today's post talking about fireworks. I love watching fireworks - the colors, the shapes, the sizes, and the different ways they twirl and burst and shimmer and sparkle are all entrancing to me. In thinking about fireworks, I wanted to investigate and see if what I think I know about fireworks is really true. In particular, I wanted to look into the science behind what makes fireworks different colors. I believe that I already know a little bit of the answer (as may you), but since it never hurts to have our knowledge expanded upon, here we go...

First, let's talk about the kind of firework that we are most familiar with in fireworks displays during the 4th of July - skyrockets. Skyrockets are projected into the air before they explode (unlike ground fireworks such as catherine wheels, which are like small, glowing ferris wheels that spin as they burn). These are built around a basic design - paper or pasteboard tubing filled with a combustible material, called pyrotechnic stars. Different tubes filled with different pyrotechnic stars can be combined in various ways to make the many shapes, sizes and colors that are seen when the firework explodes.

Pyrotechnic stars contain 5 basic components. First, there must be a combustible fuel to burn. Second, there is an oxidizer. This provides the oxygen required to start the burning process in the first place. (For a reminder about oxidizers, you can read my entry on flaming gummy bears.) Third, there is also something to hold the entire firework together, called the binder. And finally, there are chemicals which burn to provide the color, as well as another chemical to help strengthen the color of the flame produced.

So I was right - the color is provided by the burning of certain chemicals. Here's something I didn't know - a few of the chemicals that are used in producing fireworks displays:
Red: strontium or lithium salts
Orange: calcium chloride or calcium sulfate
Yellow: sodium salts such as sodium nitrate or cryolite
White: magnesium, aluminum or barium oxide
Green: Barium chloride
Blue: Copper chloride
Silver: Titanium or magnesium

Apparently, the most difficult color to achieve is blue. That's because copper is a tricky metal to burn. If it does not reach a high enough temperature, it will not emit enough light to be seen. However, if it gets too hot, it will fall apart before it produces any light at all. So consider yourself lucky if you wee a blue firework! Actually, all of the color-producing chemicals have to be handled carefully to achieve the right color. If there is a small amount of chemical impurity, thee metal will not burn properly. In particular, trace amounts of sodium burn so well that they easily overpower the intended color, producing yellow-orange instead.

I think my favorite kind of firework is called the willow firework. What's a willow firework? Well, your basic firework is called a peony. It makes a spherical burst of colored stars. Building off that, your next most common firework is the chrysanthemum, which is like a peony but with longer burning stars which leave a visible trail behind them. The willow firework is a variation on a chrysanthemum, but it has extremely long burning silver or gold stars. These burn so long that a long trail of sparks can be seen falling gracefully to the ground, just like a weeping willow tree.

Unfortunately, this year we probably will not watch a display of fireworks ourselves, but we may get to watch one on TV. Of course, it's not quite the same as in person, but it's better than nothing!

Catnip - a really good kitty drug

I've said it before, and I'll say it again - science is everywhere, all around us, in so many different things that we see all the time. I am reminded of that quite frequently when I spend a few minutes looking at our cats. There are many things that our two kitties do that spark questions in my mind, and today is no exception. What I want to explore today is the following question - how does catnip work?

For those of you with cats, you are probably familiar with what catnip does to a cat. But for those of you who don't, let me describe a scene for you. We have a toy for our cats that is a catnip-stuffed mouse. Fairly standard, as far as housecat toys go, but this one is a cut above most catnip-stuffed mice in that it has a pouch inside of it that you can refill with new catnip. So as the cats play with the mouse, though the catnip (a) slowly loses potency and (b) slowly leaks out of the pouch, it doesn't matter, because we can put new, fresh catnip in. Now, right after we fill the mouse with new catnip, it's quite amusing to watch our cats play with it. They rub their faces all over it, they lick it over and over again (until it's drenched in cat spit), they bat it around and around and around, and then they run like maniacs chasing it. And, just so you know, this is the only toy that causes them to act like this. (This is not really normal behavior for them). It's the fresh catnip - they love it. Love, love, love, love, love it! And from what I understand, our cats are not alone in their catnip obsession. Many cats love catnip. About 70-80% of domestic cats have some sort of reaction to it. They love to smell it, roll in it, lick it, rub their faces in it, and it tends to make them go a little bit nutso. Honestly, it's like a kitty drug!

So I was watching this unfold the other day, and I wondered - why does catnip affect cats so strongly?

Catnip is an herb related to mint. It's native to Europe, Asia and Africa, but has long since been established in the Americas, too. It's not entirely clear why it has such a potent affect on most cats, but here's what I've been able to find out. Catnip leaves contain a volatile oil (volatile means that it vaporizes easily) called nepetalactone. The nasal passages of cats is sensitive to this oil; when cats smell the oil, it stimulates sensory neurons that transmit messges to several parts of the cat's brain. In particular, it stimulates the amygdala (which controls emotional response to stimuli) and the hypothalamus (which regulates lots of different activities including emotions). The stimulation of these two areas of the brain cause the intense emotional reaction to the herb.

There are a few things that should be noted about catnip. First, cats will become desensitized to it after a few minutes. This seems to be analogous to how our noses become desensitized to a particular odor if we'rearound it long enough. A cat will only respond to catnip for a short while, then it ceases to have an effect. However, if they walk away from it for a while, then come back, their noses will be sensitive to it again. Second, it is not addictive. Cats do not become dependent on it, no matter how much of it they have. Third, it apparently has no effect in humans. This is presumably because our noses do not have the receptor for the nepetalactone oil. And finally, even large cats like tigers and lions appear to be susceptible to it.

I think it would be fairly amusing to watch a big, ferocious tiger rolling around, rubbing his face in a catnip bush! It would strike me as fairly undignified, for what is otherwise a thoroughly dignified animal.

New creatures

As I was scanning through the news this morning, I came across a story on msnbc entitled “Top 10 new species: only the coolest, weirdest – and deadliest – made the list.” Intrigued, I scrolled through the pictures on new life forms that have been discovered in various places on the planet over the last year. Here are a few highlights from the article:
Magaceras briansaltini: this is a new kind of rhinoceros beetle. Rhinoceros beetles are certainly nothing new, but this one has a completely different kind of horn than anyone has ever seen. Well, that’s not completely true – the horn has been seen before, but only in an animated cartoon. Remember Dim, the beetle from the Pixar movie “A Bug’s Life”? This new beetle looks exactly like him – only it’s black, not cartoon blue.
Xerocomus silwoodensis: This new mushroom species was discovered, surprisingly enough, in the relatively high-traffic area of Silwood Campus, a campus of Imperial College in London. Odd, how no one noticed it before this year, isn’t it?
Oxyuranus temporalis: This is the second most poisonous snake ever discovered. The other snakes that compete with this guy in terms of lethality are its 2 closest relatives – the inland taipan snake and the coastal taipan snake (which are ranked numbers 1 and 3 on the scale of snakes you don’t want to bite you). It was found in an isolated region of Australia.
Desmoxytes purpurosea: This one tops the list of these new creatures on my “yuck” scale, because it is a big bug with lots of legs. (You might remember from several of my previous posts that I’m not a big fan of bugs.) It’s a millipede, and what makes this species worthy of note is its shockingly bright pink color. It’s so pink, it almost looks fake – but apparently, its notable color is enough to scare away most would-be predators. That’s good for the predators, of course, since this creature also happens to be very inedible – spiny and poisonous.

The list also had a new jellyfish (highly toxic), a tubular plant (described as “having the appearance of the Michelin man”), and a frog specimen preserved in a museum that is now believed to be extinct in the wild. I knew that this list was merely the 10 new species this particular author found most interesting, and I wondered what other new species have been reported in the last few years that didn’t make the cut. Here are a few of the other new creatures that I’ve come across that I thought were worth note:
Rhynochocyon udzungwensis: This is a new type of giant elephant shrew, or sengi. The size of a house cat, this creature looks a but like a cross between a small anteater and a miniature antelope – 4 spindly legs, a stout, amber-colored body, a grey face, and a long, flexible snout. Despite its name, it’s not really a shrew at all, but a relative of African mammals like elephants and aardvarks. There are some 15 species of sengi previously known, but this one had never been sighted before, until first caught on film in the Ndundulu Forest in Tanzania’s Udzungwa Mountains in 2005.
Melipotes fumigatus: This is the only bird I’ve included in my list. It was discovered in New Guinea, on the same expedition that found numerous other species (including 20 new frogs that I won’t talk about here.) This bird is also known as a smoky honeyeater, and it is the first new bird species to be discovered on New Guinea for nearly 70 years.
And finally, Dendrolagus pulcherrimus: This species is more commonly referred to as the golden-mantled tree kangaroo. Also discovered on New Guinea, it’s the rarest arboreal, jungle-dwelling kangaroo in the world. Actually, I’ve cheated a little by including this species, since it was already known to exist in the Foja Mountains of Indonesia, but this is only the second place in the world that the animal has been sighted. But I included it, because I think it’s the cutest of the entire bunch I’ve looked at!

All in all, hundred of new species have been described over the last year. These creatures run the gamut in type, habitat, size, shape and purpose - parasites, plants, fungi, insects, fish, birds, mammals, and amphibians. Of course, since they’re so new, not much is known about many of them yet! I think it’s amazing that, despite the global nature of today’s world, there are still so many things about our planet that we don’t know. And these mysteries are not always even found in the deep jungles of New Guinea – sometimes they’re found right under our noses, or in the courtyards of the Imperial College in London.

The power of oses

Today I’d like to write about oses. What, you might wonder, are oses? Well, that’s actually a nickname I’ve come up with for the wide variety of sugars that are found in the foods that we eat. Since the proper name for all sugars ends in –ose (I’ll give you a few examples in a minute), I like to call them all “oses.” (It saves me some effort.)

When I say sugar, you might think of granulated sugar, that gritty white stuff we use to sweeten things when we cook. But that is only one specific kind of sugar – specifically, it is sucrose. (See, it ends in –ose.) There are actually dozens of varieties of sugars in the world. What, chemically speaking, is a sugar?

Sugar is a carbohydrate. Carbohydrates come in 2 basic varieties, actually, sugars and starches. Starches are the biggest source of carbohydrates that we eat, but sugars are themselves very important sources of carbohydrates, as well. There are 4 major kinds of sugar that we come into contact with regularly – 3 come from plants and 1 from animals. The 3 plant sugars are called sucrose (what we know of as baking sugar), fructose and glucose.

Fructose is the sweetest of all natural sugars. Its chemical structure is very simple – 6 carbons, 6 oxygens, and 12 hydrogens. It is found in a variety of plant sources, including tree fruits, berries, melons and root vegetables. Chemically speaking, it is actually very similar to glucose; they both have the same numbers and types of atoms, those atoms are simply connected differently in the 2 different sugars. Glucose is the least sweet of the three major plant sugars, but it is the primary source of energy for living cells of all kinds (plants and animals). Sucrose is also commonly known as saccharose, and it is known as a disaccharide. That means it is made up of 2 pieces of glucose and fructose that are bonded together in a specific way. It is the plant sugar that is intermediate in its sweetness between its 2 cousins.

Various food items that we think of as sweet usually actually contain a mixture of the three plant sugars. For example, honey is a mixture of glucose, fructose and sucrose (80% sugars, 20% water). Maple sugar (which makes up maple syrup) is mostly sucrose. Molasses is a byproduct of sugarcane or beet sugar, which is also primarily sucrose. High fructose corn syrup is actually only about 45-55% fructose, the rest of the sugar being a mixture of sucrose and glucose.

The 1 major animal sugar is called lactose. Lactose is found in the milk of all mammals, though it is not as sweet as the plant sugars That means that, though milk has a relatively high sugar content, it doesn’t taste as sweet as something sweetened with sucrose, fructose or glucose. Of course, the rest of a mammal’s body (blood and muscles) also contains sugar in the form of glucose. After all, it is the major energy supply for metabolism. However, mammals do not synthesize glucose out of the constituent atoms – they produce it by converting any other kind of sugar they eat into it.

I know that sugar gets a bad reputation, some of it deserved. After all, our diets are higher in sugar (eg higher in sucrose) than is probably good for us. And a little sugar goes a long way, so we don’t really need to eat as much as we do. But sugar does have a very important place in our metabolism, as well as in making food palatable (actually, making it quite yummy sometimes). So don’t throw the baby out with the bath water, equating sugar with all things bad and horrible. Like everything, just take in moderation.

Antacids - chemistry in action

Since becoming pregnant, I’ve become acquainted with an uncomfortable stomach reality – heartburn. Or, more properly termed, pyrosis. If you’ve never had heartburn before, let me introduce you to the phenomenon. Your stomach is a very acidic environment – it has to be, to digest everything that you eat. The acid produced by your stomach is supposed to be kept in your stomach and out of your esophagus (the tube connecting your mouth to your digestive tract) through the action of the esophageal sphincter. It’s supposed to be a one-way valve that lets food and liquid from the esophagus into the stomach, but not the other way around. However, sometimes that sphincter doesn’t work very well, and stomach juices push up out of your stomach and into your esophagus. And as these juices are strongly acidic, they can burn whatever they touch; in this case, that would be the lining of your esophagus. This doesn’t really have anything to do with your heart, making heartburn rather poorly named. But since the burning sensation occurs right behind your breastbone, and in severe cases, radiate through the rest of your chest, I guess it makes sense for it to have gotten that name somewhere in the past.

Okay, so that’s heartburn – a burning sensation occurring in your esophagus. Fortunately for mild cases, there is a very simple remedy. Antacids. How do antacids work? It’s actually very simple chemistry in action. To stop heartburn, you want to stop the ability of the rising stomach acid to burn your esophagus. In other words, you want to neutralize the stomach acid. The opposite of an acid is a base. If you combine an acid and a base, they cancel each other out , resulting in something either neutral or closer to neutral than you started with (depending, of course, on the strength of each one). So, very simply, antacids contain some sort of base to help neutralize the stomach acid they encounter.

There are multiple kinds of antacids, each using a different chemical formulation to help neutralize stomach acid. Some, like Tums, use calcium carbonate. Others, like Alka-Seltzer, use sodium bicarbonate instead. There are also magnesium salt-based antacids, like Maalox and Mylanta. Each formula works very effectively, but there are limitations to them. People with hypertension have to be careful not to ingest too much sodium, so sodium bicarbonate antacids may not be recommended. And excess calcium or magnesium can cause kidney stones, so you don’t want to take too much of the other ones, either. All in all, antacids are like any over-the-counter medicine, I guess – you still have to be smart with what you take.

Incidentally, pregnant women frequently experience heartburn because there is less and less room in the abdomen as the baby grows. This puts pressure on the bottom of the stomach, often pushing the stomach juices up into the esophagus. But it’s not really that big a deal, at least for me. A few Tums usually clears things right up!

Yay for chemistry in action!

The rubella vaccine

Today I want to write about something that has bothered me for a while, but which has intensified since I became pregnant. And I know that I run the risk of jumping into a rat’s nest of controversy, as there are many people who passionately believe in one side or another of this controversy. But hey, science is sometimes controversial, so I’ll just take a deep breath and plunge right in.

I want to talk about childhood vaccinations.

You might have heard a lot of stories on the news or in the papers in the last few years about the controversy over vaccinations. Do kids really need them, should they get them, or (and this is really the favorite topic in the media) is the increase in the rate of vaccinations connected with the increased rate of autism in today’s children?

I consider myself very well educated on these topics, and let me just put my position out there. I do not believe there to be any credible scientific backing behind the purported link between vaccinations and autism. I think any “scientific” evidence supporting it is spurious at best. I understand that autism is on the rise among today’s children, my heart breaks for those families with autistic children, and I easily understand how they might want an answer for what has caused the condition. But the science just does not support their claim that it is due to vaccinations.

That’s all I want to say about the recent controversy over vaccines. The main focus of what I want to say about the decision of whether to have your children vaccinated or not is not simply, as I have heard it said, a personal decision. Yes,, it is personal. But it is also a social decision as well. Here’s what I mean.

Rubella, or German measles, is not a very common disease these days (at least in the US). That’s because vaccinations against rubella have been going on for years – it’s a part of the MMR vaccine, and it’s very effective. Some may argue that it’s silly to vaccinate against rubella. Actually, compared to regular measles, rubella is usually pretty mild. You might have a rash, low grade fever, swollen glands, headaches and body aches. Or you might not ever really notice that you have it at all. But here’s the sticky thing. While rubella might not be all that dangerous for children or adults, it is devastating to pregnant women and their unborn children. A pregnant woman who contracts rubella within the first 20 weeks of her pregnancy has a significantly increased risk of spontaneous miscarriage. And even if disease doesn’t kill her child, it is at high risk for congenital rubella syndrome. This syndrome includes a host of birth defects, including heart malformations, deafness, mental retardation, eye defects, low birth weight, or problems with the spleen, liver or bone marrow. These problem can plague a child for the rest of his life.

The easiest way for mothers to protect their unborn children against congenital rubella syndrome is to be vaccinated themselves. That way, even if they encounter someone with rubella, they and their baby will be protected. But here’s what I worry about: I’m sure there are plenty of women who don’t know of the dangers that rubella poses. And so their vaccinations are not up-to-date. What if they come into contact with someone else carrying rubella because they believe that “whether or not I get vaccinated is strictly a personal decision that doesn’t affect anyone else”? I hope that you clearly see that suddenly this is not simply a personal decision. The unvaccinated individual has significantly increased the risk of someone else being born with a serious birth defect – or perhaps even caused the baby to not be born at all. That’s not personal. That’s social.

I realize that I’m not going to sway anyone’s opinion on whether or not they or their children should be vaccinated. (Especially if their belief is based on religious reasons.) However, I just want to make people aware. This really is not just a personal question, and it makes my blood boil, both as a scientist and an expectant mother, when people suggest that it is.

Incidentally, for everyone who’s reading this – have you been vaccinated against MMR?

The intelligent octopus

I wrote about giant squid recently, which prompted thoughts on a related topic in my head. I’ve read before that octopus are really intelligent creatures. But I’ve never actually investigated that claim very closely; I’ve just taken it at face value. So I wondered – is it true? How smart are octopus, anyways? And how do we know how smart they are? Is there a little octopus IQ test given to all eight-legged water-dwellers currently residing in aquariums around the world?

Remember, an octopus is a kind of cephalopod. Cephalopods are classified by bilateral body symmetry, prominent heads, and a variation on a mollusk foot called a muscular hydrostat – aka arms or tentacles. (FYI, a muscular hydrostat is a piece of anatomy found in any animal that has muscle but no skeletal support and that is used to move stuff – such as food – around. Your tongue is a perfect example of one.) There are two major types of cephalopods – those with a mollusk shell (like the nautilus) and those without (like squid and octopus). The octopus takes being shell-less even one step further than many of its relatives, however, because it has no skeletal support at all. It doesn’t even have any vestiges of an internal shell or bones, unlike cuttlefish or squid. Its body is entirely soft.

You’d probably agree that an octopus does, indeed, have a noticeably large head. And housed within that head is a very large and complex brain. In terms of brain size relative to body mass, octopus brains rank higher than those of reptiles and fish. And while their brains are organized very differently from that of vertebrates, there is no denying that it is highly differentiated and organized into different sensory processing centers. So that brings us to the question of how intelligent these creatures are. If they have such large brains relative to their body size, it would make sense that they would be intelligent, right?

The answer is – maybe. It depends on whom you ask. Some scientists believe that the size of the octopus brain is not a sign of intelligence at all, but merely an indication that their entire brains are not built very efficiently. And there may be some backing for that. In fact, octopus have been discovered with spines lodged in their brains, from where a meal that they were eating went the wrong way through their system and got wedged in their heads. That’s a pretty good indication that there is something a little screwy about the way their digestive and nervous systems intersect.

However, others believe that octopus have large brains because they are intelligent. When they say “intelligent,” what they really mean is capable of highly complex behaviors above and beyond simple survival skills. Here are some examples of the evidence that scientists falling in to this camp cite as backing for their belief.

1. Captive octopi are extremely good escape artists. Lids of tanks must be heavily weight shut, or the creatures will use their arms to push their way out. Even then, the areas around octopi tanks are frequently carpeted instead of tiled. That’s because octopi can manage to squeeze through incredibly small spaces (remember, they have no bones). So even with a heavily weighted lid, they still sneak out. But they can’t crawl across a carpeted floor, so they have nowhere to go but back where they came from. When they do manage to escape, where do they go, you might wonder? Usually, they are found in neighboring tanks, snacking on whatever tasty treats they find there.

2. Octopi are highly adept at changing their appearance. They can change the color and texture of their skin at will to match their surroundings. Their appearance can change from solid colors to lightly speckled to dramatically striped very rapidly during hunting, courtship, male-to-male aggression and in response to a threat. They accomplish this through the stretching of chromatophores, which are multicelled organs consisting of pigment sacs and various colors. When their muscles fibers contract and expand, the chromatophores change within seconds, making the octopus much faster at changing appearance than any land-based camouflage artist.

3. Researchers have trained octopi to recognize shapes, colors and textures in much the same way that they would teach vertebrates like rats. In the 1950s and 1960s, scientists at the University of Cambridge taught young octopi how to recognize small and large squares, horizontal and vertical stripes, and black and white circles. And the octopi were quick learners, too, though it seems like their maximum level of knowledge is ultimately below that achieved by rats.

4. Octopi are highly skilled navigators underwater, and have been trained to run through mazes just like mice and rats. When presented with a new underwater terrain filled with holes, an octopus can quickly learn to navigate through the correct holes to get to its den (and a treat). And once it’s figured the route out, it is much faster at navigating it the second time through.

5. Octopi have been shown to be able to solve the “food in a container” challenge. If given a closed jar with a crab inside (crabs being a very tasty octopus snack), most octopi will figure out how to open the jar and get their treat, even if they’ve never seen such a jar before. Incidentally, this is a classic test of problem-solving ability in vertebrates such as non-human primates.)

6. There was even one study in 1992 claiming to show that octopi could learn by observing other octopi. According to the study, an octopus was allowed to observe another octopus being trained to prefer one color ball (red) to another (white). Later, the observer octopus showed a preference for red balls, even though he had not received the training himself. This study has been met with much skepticism, however, and it is generally agreed that it must be rigorously repeated before it can be taken at face value. To date, no one else has been able to reproduce the results under more rigorously controlled conditions, so the jury is still out on that question.

This debate rages on even now, as scientists try to come up with the perfect experimental set-up to test whether the octopus is really intelligent, or simply very good at navigating in its surroundings. Regardless, I love watching octopi at aquariums. Whether or not they are as smart as some claim, they are fascinating creatures nonetheless. I’ve never seen one in the wild, though I’ve often looked (while scuba diving). Who knows – maybe some day I’ll get lucky enough to see one in the ocean!

Why don’t they go bad?

This post is for anyone who’s ever ordered coffee at a restaurant and wondered about the little cups of creamer that they bring with it. These creamers hold maybe a tablespoon full of cream that tastes actually tastes pretty decent in your average cup of coffee, but they also have an inherent mystery about them that has always puzzled me a bit. You see, unlike regular milk or cream, these little things do not need to be refrigerated. Says so right on the lid – no refrigeration necessary. And yet, if you look at the ingredients, there is actual milk in there. So why doesn’t it go bad?

To answer this question, let’s first look at how regular milk is processed for sale in the US. Milk (as well milk-related products like cream and non-dairy products like juice) undergoes a process called pasteurization before it is put on the market. Pasteurization is a process by which any liquid is heated to destroy any microorganisms in it, such as bacteria and mold. It’s named after Louis Pasteur, a famous French scientist who accomplished many things over the course of his life, including advancing the idea that diseases are caused by germs and for developing a vaccine for rabies. He also figured out that heating liquids to a temperature below their boiling point would significantly extend their shelf life (the amount of time before the liquid spoils). There are 2 major methods for pasteurization in use today – High Temperature/Short Time (HTST) and Extended Shelf Life (ESL) treatments. These different methods just use different machinery to achieve the same end. Pasteurization is different from sterilization, in that it is not designed to kill all of the microorganisms within the liquid. Instead, it results in a logarithmic reduction in their levels, reducing them to a point where they are unlikely to cause disease as long as the product is refrigerated. However, as anyone who has ever left a carton of milk in the fridge for too long knows, even a pasteurized product will go bad eventually. That’s because there are still some microorganisms left in the liquid that will cause it to curdle, sour, or otherwise go bad after enough time. If you were to leave the milk out at room temperature, the residual bacteria would spoil the milk even faster – even as fast as overnight.

So if they contain real dairy, why don’t those little creamer packages go bad when left out overnight, too? Well, it turns out that those things undergo a slightly different process called ultrapasteurization. This is also known as ultrahigh-temperature pasteurization, or UHT. Ultrapasteurization is really a process of sterilization instead of pasteurization. When a product is ultrapasteurized, it is heated hotter than in regular pasteurization. This results in the killing of all microorganisms within it – they simply can’t survive the heat. And without any microorganisms, the liquid simply won’t go bad – at least not for a very long time. You can keep ultrapasteurized dairy at room temperature for months if it has not been opened, and it will still be as good when you open it as when it was first produced. Of course, once it is opened, then you need to refrigerate it. That’s because there are numerous bacteria and mold spores floating around in the air, covering your skin, and on every surface in the world. So when that package is opened, those little beasties can get inside and work their destructive magic.

So there you have it. You don’t need to refrigerate little packets of creamer because they have been sterilized. Just another example of science making a difference in little aspects of life you may never have realized!

How to see the inner man (or woman)

There is a major event happening in the life of my family right now, and I haven’t written about it yet but have been waiting for the opportunity. My husband and I are expecting our first child! There are so many things that I’ve thought about writing with respect to the science of pregnancy – what causes morning sickness, how amazing the pattern of development of the human body really is, how statistically unlikely it was that we would have twins (though lots and lots of people teased us about the possibility), and how much I hope our child grows up loving science as much as we do. But I held off, waiting for the perfect topic. And today, I think I’ve found it – I want to write about ultrasounds.

Actually, I’d like to write about some of the various ways that medicine has come up with to look at what’s going on inside the human body – short of surgery, that is. Three big techniques come to my mind, and I’d like to take a few minutes to discuss what each one does, how they are different from each other, and what their advantages are. These three are ultrasounds, x-rays, and MRIs.

I’ll start with the ultrasound (particularly near and dear to us at the moment). The word “ultrasound” actually means sound waves that are above the range of human hearing (20,000 hertz), so when we talk about ultrasounds in a medical sense, we are actually talking about ultrasonography. Ultrasonography has been around for about 50 years, and is extremely widely used in diagnostic procedures to visualize soft tissues, muscles, tendons, and some internal organs (including the heart, liver, gallbladder, kidneys and bladder). It is also commonly used to look at a developing fetus within a mother’s uterus. During the process, ultrasound waves are produced by a small wand, or transducer, which radiate out into the body to focus at the specified depth. This sound wave is partially reflected from the layers between different tissues – specifically, where there is a change in tissue density. The sound waves that get bounced back towards the transducer are detected by a sensitive microphone, which are then translated into an image on a computer screen. There are several big advantages to using sonography as a diagnostic tool. For one thing, it does not use ionizing radiation (as do x-rays), making it safe to use for developing babies. For another, it is relatively cheap compared to its high-power brothers like the MRI. However, it is limited in its ability to see certain structures within the body – it is not good at visualizing bones or the brain, for example.

So let’s go now to the next imaging technique on my list – the x-ray. The medical use of x-rays manipulates the physical properties of – you got it – x-rays. (Clever, huh?) An x-ray is a high energy type of light wave. The energy of a light wave can be measured by its wavelength – the shorter the wavelength, the higher the energy the wave has. In the visible spectrum, red light has lower energy (and longer wavelengths) and blue light has higher energy (and shorter wavelengths). Past the visible spectrum comes ultraviolet light, followed by x-rays. While visible light does not have enough energy to pass through your skin, x-rays have considerably more energy, and thus can pass right through your skin and muscle. However, they are not strong enough to pass through bone. So when you undergo a medical x-ray (for example, to see whether you’ve broken a bone or when you are at the dentist), the doctor will put you in front of an x-ray emitter, which sends x-rays through your body and picked up by a detector (usually a piece of film) on the other side of you. Places of your body where the x-rays pass through (eg muscles and soft tissue) show up as black, while pieces of your body where the x-rays were absorbed (eg bone and teeth) show up white. The film is developed, and the doctor can tell whether your bones are all as they should be – whole and unbroken (hopefully). X-rays are more powerful than sonograms, especially for diagnosing problems specific to the skeleton. However, their major drawback is that they use ionizing radiation in the process. Too much ionizing radiation can cause all kinds of problems for your cells and tissues; however, the exposure any of us will be likely to receive from medical x-rays over the course of our lives is minimal and of low risk.

What about the fancier techniques, like MRI? MRI stands for magnetic resonance imaging, and it uses an entirely different basic principle to visualize the interior of the human body. Instead of sonography (which uses sound) or x-rays (which uses high-energy light), MRIs use magnetic fields. When a person is subjected to an MRI, their body is immersed in a strong magnetic field, which has an effect on the hydrogen atoms throughout their body. The human body can be upwards of 75% water; in each molecule of water, there are 2 hydrogen atoms. Thus, the amount of hydrogen in your body from water alone is really high. And these hydrogen ions will all align with the magnetic field when you are in the MRI machine. So you sit there, with all your hydrogens aligned, and then your body is pulsed with a radio wave. This pushes some of the hydrogen atoms out of alignment with the magnetic field. The radio wave stops, and the hydrogens all slowly snap back into alignment. However, depending on what tissue they happen to be sitting in, they will snap back into place at different speeds. And the speed at which the hydrogens align themselves with is detected by the machine, then calculated to determine what tissue is what. An MRI is a very powerful technique, and can be used to diagnose a number of different medical conditions, including multiple sclerosis, brain tumors, torn ligaments, spinal hernias, tendonitis, and even strokes in the early stages. Another advantage is that they, like sonograms, do not use any form of ionizing radiation. And yet another advantage is that MRIs can be used to look at any plane of the human body – sideways, top-to-bottom, or any other way you can think of. There are some disadvantages, though. Certain people cannot receive MRIs, because the strong magnetic field would be dangerous for them (for example, people with pacemakers). MRIs take a very long time to do, as well, and they are extremely expensive – much more so than either x-rays or a sonogram.

All three of these techniques are powerful in their own right. They can be used to look at different parts of the body – soft tissue, organs, bones or ligaments – with different resolutions. Each one uses a different major method of visualization – magnetic fields, sound waves or electromagnetic radiation. Each one has different costs, risks and benefits. And all in all, I’m glad to live in a day and age where all three are used as a part of everyday medicine. Each one is so much safer than having to cut the body open to see what’s going on inside!

Oh, and by the way, we have had our ultrasound to check on our developing baby. All looks good – 2 arms, 2 legs, and all pieces where they should be! Now we just have to wait to see the little one in person!

The giant of the deep

As you might have guessed from my various postings through the months, I like to write about animals. There are so many things about them that I find interesting – the purring of cats, lizards whose appearance hasn’t changed in a million years, goats that randomly fall over when they are startled, how kangaroos can’t walk backwards, and how, ounce for ounce, bats are one of the longest living mammals on earth. Well, today I’d like to talk about an animal that no one knows very much about, but one that I have found fascinating ever since I first heard about it. This creature is one of the great animal mysteries of the world – we know that it exists, but short of that, we know relatively little about it at all. The animal in question – Architeuthis. The giant squid.

What is a giant squid? Since it is not very creatively named, you’ve probably guessed that it’s simply a really, really big squid. But how big is it? How does it get so big? Where does it live? And why do we know so little about it?

First, let’s discuss squid and octopus in general. Your basic squid has a few standard anatomical features – 8 arms and 2 tentacles, each with hooks and/or suckers, a head (with a very large brain), a mantle (or torso), and 2 fins at the rear of the mantle. Your basic octopus is the same, except that it doesn’t usually have fins, and it’s arms and tentacles only have suckers, not hooks. (There are a few species of octopus with fins, however; they live off the coast of New Zealand and are considered primitive relative to other octopus. That’s why they are referred to as “Dumbo octopus.”) The tentacles of squid are generally much longer than the arms. In fact, there are 2 ways to measure the length of a squid. You can either measure the standard length, which is the length from fins to the end of the arms, or total length, which is the length of the fins to the tentacles. Most squid are quite small, reaching an average total length of almost 2 feet. Of course, that’s the size of most squid – except for the giant squid.

How big a giant squid can get is a matter of debate, since they are so hard to find. The largest reported giant squid ever found washed up in New Zealand in 1887, supposedly at a total length of 55 feet. However, since it was dead, it is likely that its tentacles became stretched like rubber bands once it died and washed up. Based on the length of its mantle, it is now believed to have been only around 30 feet long. Scientists now generally base their estimates of how big a giant squid can get on the remnants of them found in the stomachs of their only known predators, sperm whales. Based on these leftovers, it is now believed that they can reach up to 45 feet in total length. The only invertebrate believed to be larger than the giant squid, actually, is its cousin, the colossal squid (which may be twice as long).

Giant squid live in the depths of every ocean in the world. They are usually found near continental and island slopes of the North Atlantic, the South Atlantic, and New Zealand and Australia, and are rarely seen in tropical waters or near the poles. Unfortunately for scientists, they are often studied after they’ve died, whether they’ve washed up on a beach or are taken out in pieces from a sperm whale’s stomach. In 2004, however, major news was made when scientists off the coast of Japan filmed a live giant squid for the first time ever in its natural habitat. Finding live giant squid in the ocean is notoriously difficult. Scientists usually try to follow sperm whales in the hopes of finding one, but that has proved relatively fruitless. Unless we come up with a better way of finding these elusive giants, they might remain a mystery for some time to come.

Of course, just because we don’t know a lot about them scientifically hasn’t stopped us from using our imaginations to envision them. Giant squid have been a source of legend for thousands of years. Tales of them have been around among mariners since ancient times. In fact, it is believed that the giant squid probably gave rise to the legend of the kraken - a giant sea monster off the coast of Norway and Iceland that was capable of engulfing entire ships (and one that you might remember from the recent Hollywood blockbuster “Pirates of the Caribbean 2: Dead Man’s Chest").

I don’t know why I find these creatures so intriguing, to be honest. Perhaps it’s simply because of their mystery. Imagine – an enormous creature, swimming in the depths of the ocean, so well adapted to its environment that we can’t even find it. Something so large that it only has one predator it needs to fear. And something that, unlike sharks, has not successfully been made into the villain of a Hollywood movie plot such that we feel the need to hunt it down and kill it. Maybe someday we’ll know more about this giant animal. Until then, I must say that I kind of like the uncertainty.

Reversing revisited

In my last post, I talked about the ability to walk backwards, with the following conclusions: kangaroos – no ability to walk backwards; emus – ability to walk backwards unverified. Apparently, in the book that I mentioned (“Emus can’t walk backwards: Another round of dubious pub facts”) I have been told that the author describes experiments done in Australia to demonstrate that emus can, in fact, walk backwards. I’d be interested to read it, learn the evidence for myself, and also to know whether it describes the origin of this fable. (Really, emus are not all that popular an animal to discuss in everyday conversation! So who started the idea that they can only walk forwards?)

Anyways, I’ll see if I can check it out from the library. This is good - this could save me a long time sitting in front of the emu exhibit at the zoo, waiting for one of them to back up.

Ready, set, reverse!

Our cats really love to sit on the counters in our bathrooms. Every morning, as I’m getting ready for work, our older cat will come and sit on the counter for a few minutes – until I pull out the hair dryer, that is. The noise of this machine always scares her, and she inevitably jumps down off the counter and scampers away. A few days ago, however, she tried a new technique for getting off the counter. Instead of turning around and jumping down, she simply backed herself right off the edge. Not surprisingly, this didn’t work very well – she misjudged where the counter ended, and wound up with her rear legs in the trash can and her front legs on top of the toilet seat! (I guess I should be glad she didn’t wind up with her back legs in the toilet bowl.)

Now, I must admit, I laughed quite a bit at her predicament. (After making sure she as unhurt, of course.) But it sparked a question in my mind. She can back up quite well, but apparently she has to be level ground. And I wondered if that was a trait that all animals share. Can any creature that walks forwards also walk backwards? Or are there animals in the world that are physically unable to back up?

For the most part, animals that can walk forwards can also walk backwards. However, it is not universally true.

The one mammal that I came across that is unable to back up is the kangaroo. Kangaroos are marsupials that belong to the family Macropodidae, which means big feet. Other macropods include wallabies, quokkas, pademelons, honey possums, and wallaroos – in fact, there are over 50 different species of macropods. The most obvious difference between kangaroos and other species like wallabies and wallaroos is size. The 6 largest marsupial species are all referred to as kangaroos. In addition to really big feet, kangaroos have very powerful leg muscles, a strong tail for balancing, and a skeletal structure that makes them very efficient hoppers. But it also means that they can’t really walk. If a kangaroo has to move slowly, it forms a tripod between its tail and two forelimbs. You might see a kangaroo in this position if it’s eating something from the ground. But for general locomotion, hopping is much more efficient. And apparently if a kangaroo wants to retrace its steps (its hops?) it must turn around to do so. They cannot hop backwards, nor can they mince backwards in their tripod walk.

It has also been reported that certain birds are unable to walk backwards – in particular, ostriches and emus. These are the two largest birds on the planet; they are both members of the most primitive of modern bird families (including kiwis, cassowaries, and rheas). Both flightless, these guys rely on good old-fashioned leg power to get themselves around. Emus, in particular, can be quite speedy – they can sprint upwards of 30 miles an hour! They have a unique structure to their pelvic bones and muscles that allow them to move so quickly. They also have extremely powerful legs - in fact, emus are also the only birds that have calf muscles. Not only can emus run really quickly, their strong legs make them incredible jumpers. If startled, they can jump straight up almost 7 feet – which, considering that the bird itself is over 6 feet tall, is quite impressive. So they can move really well going forwards – but can they reverse? Unfortunately, though that statement is often thrown around as fact (and is even the title of a book – “Emus can’t walk backwards: Another round of dubious pub facts”), I wasn’t able to find any reliable source to tell me whether or not it was true. The evidence is mostly anecdotal. I guess the next option to me to verify this fact would be to camp out at the emu section of the local zoo and watch them for a few days to see if I can see any of them go backwards!

There may be other animals that cannot reverse their locomotion. One other suggestion my husband came up with was the centipede. With that many legs, I can imagine that it might very well be difficult for organize them all to go in reverse!

Anyone have any other ideas?

Yikes! Brain Freeze!

Here in the Seattle area, we are going through a rather disappointing spring. With the exception of 1 very notable day, our weather has been much colder and wetter than usual. Now, I love warm weather. Give me sun, sun, sun! So I’ve been having a hard time being patient for the nice weather to return. When I think about warm weather, I think about lots of things associated with summer time – barbeques, running through the grass in my bare feet, seeing our cats sunning themselves in the windows, listening to the birds outside, and, of course, all the yummy summer food. Especially ice cream. I really like ice cream. The only downside to eating ice cream on a warm summer day, unfortunately, is the chance of developing brain freeze.

Have you ever had brain freeze - that feeling when you’re eating something really cold (could be ice cream, or a slurpee, or some ice cubes in a drink) and all of a sudden you get a horribly painful ache in the front of your skull? Fortunately, it only lasts a few seconds, which is a very good thing since it hurts so badly. Have you ever wondered what causes it?

Brain freeze occurs when your palate gets a little confused over the temperature. Your palate is, basically, the roof of your mouth. If you run your tongue over the roof of your mouth, everything from the ridge behind your teeth to the farthest back you can reach is the palate. It is made of both bone and muscle, and is covered by a layer of skin. It serves several important purposes, including separating your nose and nasal cavity from your mouth. There are many nerves and blood vessels situated in this region, which are all sensitive to the things you eat. When you eat something very cold very quickly, the nerves in your palate get a strong message that there’s something freezing here! These nerves then get a little confused – they think that your brain is in danger of freezing from the cold. And since a frozen brain would be very bad for your health, these nerves send an immediate message to increase the blood flow to your head. Increased blood flow would mean extra warmth for your brain, keeping it safe from freezing. However, the blood vessels holding this extra blood in your head expand so quickly that they cause pain. The pain is very short-lived – the increased blood flow stops as soon as your palate warms up a little, your blood vessels contract again, and the headache stops.

One thing that surprised me is that not everyone suffers from brain freeze. Apparently, it only happens in 30-40% of the population. (The American population, that is.) I guess that makes me one of the unlucky ones, since I definitely get them! I did learn one new way of getting the brain freeze to go away faster, though. When you feel it start to develop, press your tongue against the roof of your mouth. This will warm your palate up faster than it would otherwise, and stop the headache faster.

Or you could just eat your ice cream a little bit slower.

The Oregon earthquake swarm

I live in western Washington, an area not as well-known as California for being earthquake-prone but which is nevertheless earthquake territory. That's because we're right on the edge of the North American tectonic plate, which runs almost directly up the western coast of North America. When you think about the fault lines created by this boundary, you might think first of arguably the most famous fault line in the US – the San Andreas fault. The San Andreas fault stretches approximately 800 miles up the coast of California; here, the passage of the North American plate (which moves southeast) and the Pacific plate (which moves northwest) generates the most memorable earthquakes of the region. This includes the devastating 1906 San Francisco quake, which was an estimated 7.8 on the Richter scale and responsible for some 3000 deaths.

Now, the San Andreas does not extend up into Washington state. However, being at the edge of the North American tectonic plate means that we also have fault lines capable of generating substantial earthquakes in the area. For us, however, the danger comes primarily from where the North American plate meets the Juan de Fuca plate. The Juan de Fuca plate is very small, extending from the southern border of Oregon to British Columbia, Canada; it was once part of a much large plate (the Farallon plate) that has largely subducted (meaning sunk) underneath the North American plate. There are three remnants of the Farallon plate still in existence - the Juan de Fuca plate off of the Washington coast, the Cocos plate off of Central America, and the Nazca plate along the western edge of South America. Subduction of the Juan de Fuca plate is responsible for the formation of the Cascade mountains which includes two volcanoes that you might be familiar with - Mount St. Helens and Mount Rainier.

The last major earthquake to occur off a fault from the Juan de Fuca plate was around 1700, with a magnitude of somewhere around 9.0 on the Richter scale. However, in the last 2 weeks, scientists have detected a rash of earthquakes off the Oregon coast – over 600 of them, up to a magnitude of 5.4. But here’s the odd thing – these earthquakes do not appear to be coming from any of the fault lines from the Juan de Fuca plate. Instead, they are centered in the middle of the plate – about 40 miles from its edge.

There are actually several odd things about these earthquakes. First, of course, is that they do not correspond to a fault line. But second, they do not follow the typical earthquake swarm pattern of a major shock followed by steadily decreasing aftershocks. It has been a steady stream of earthquakes of mostly equal size. That means this is unlikely to be caused by a fault internal to the plate itself. In fact, scientists really have no firm idea what’s causing these tremors to occur.

One of the major researchers studying this swarm is Dr. Robert Dziak, marine geologist from Oregon State University. Though he says that nothing like this has been detected in this region ever since monitoring has begun, he has a couple of suggestions as to what’s causing the swarm. It’s possible that a new fault is opening in the middle of the Juann de Fuca plate. Or it could be that the entire plate is under stress, being squeezed by the plates around it, which could cause it to crumple a little in the middle. Or there could be new volcano activity in the area immediately beneath this spot, injecting new magma into the middle of the plate and pushing the plate much faster than it has previously moved.

I should mention that these earthquakes do not appear to be any danger to the inhabitants of the Oregon coast. The quakes are too far away, too deep and too small to even be felt on the mainland. They are detectable by a system of hydrophones set up on the ocean floor – which were actually originally set up to detect submarine activity off the Pacific coast during the cold war. But they’ve been put to a more peaceful use as of late.

Not a lizard, and not a snake - but some of both

Did you know that there is still a species alive on earth that roamed the planet alongside the dinosaurs?

It’s called the Tuatara. The tuatara is the last surviving species of the Sphenodontians, a group of animals that developed and thrived during the upper Triassic – nearly 220 million years ago. If you were to look at it, you might think the tuatara is a lizard – a triangular head, four squat legs with long spiny toes, leathery skin, and a long tail. However, while the tuatara is a reptile, it is equally closely related to both lizards and snakes. It is the only surviving species on earth that fits this description. Other relatives of the tuatara were the beak-headed reptiles (also known as Rhinocephalia), but the rest of them died out 100 million years ago.

The tuatara is sometimes referred to as a living fossil. Despite its ancient origins, the appearance of these animals has not changed very much in the last 200 million years. This means that they can be used to study what their ancient relatives looked liked. Because of this, they are of great interest to scientists who study the evolution of lizards, snakes, and diaspids (the group that includes both birds and crocodiles).

Interestingly, though the overall appearance of the tuatara has remained unchanged for millions of years, it now seems that they undergo relatively rapid molecular changes. By comparing DNA extracted from tuatara bones approximately 8000 years old to modern tuatara DNA, scientists now believe that this animal has the fastest rate of DNA changes ever measured. At an average rate of change of slightly over 1.5 subsitutions per nucleotide per million years, it beats out the previous record-holding fast molecular evolver, the Adelie penguin. The fact that the DNA of the tuatara changes so rapidly, while its overall body hasn’t changed in millions of years, is remarkable.

Tuataras live only in New Zealand. And though I refer to the tuatara as one species, there are actually 2 closely related subspecies of tuataras – S. punctatus and S. guntheri. S. guntheri is also know as the Brothers Island tuatara, and it is extremely rare, much more so than its S. punctatus relative. In reading up on these creatures, I came across a few interesting facts:
-They have the slowest growth rate of any reptile we know of. In fact, they keep growing until the reach about 35 years old, but only attain a final size of 20 inches.
-They can live to be over 100 years old, though their average life span is around 60 years.
-They can hold their breath for nearly an hour.
-They are nocturnal – for the most part. Adult tuatara hunt at night, but young tuatara will hunt during the day. This is because a really hungry adult will eat a young tuatara if it can catch it. In addition, because they are cold-blooded, they will bask in the sun during the day to regulate their body temperature.
-They have an extra eye besides the two in the front of the face. Called the parietal eye, it is found on the top of the head, and is visible only in the very young. After about 6 months of age, it becomes covered with opaque scales and pigment. Its function is unknown, though scientists have suggested it to play a role in circadian rhythms or the absorption of UV light to aid in the production of vitamin D.
-The hearing organs of the tuatara are very primitive, and look very similar to that of turtles. There is no eardrum, or even an earhole. The cells that respond to sound are relatively poorly specialized, and respond only to low frequency sounds.

If you have a few minutes, and want to see some pictures of these cool little creatures, you can check out the website of the Kiwi Conservation Club at:
http://www.kcc.org.nz/animals/tuatara.asp


The image of the tuatara was taken from:
http://www.wpclipart.com/imgpage.html?http:
//www.wpclipart.com/animals/T/Tuatara.png

A well-built skull

Why don’t woodpeckers hurt their heads when they bang them into trees?

That question popped to mind the other day as I was working outside in my garden. We have a woodpecker that has taken to visiting one of our neighbor’s trees. Stay outside long enough on a decent afternoon, and soon you will hear the distinctive “rat-a-tat-a-tat-a-tat” of the woodpecker’s beak, as it rams over and over again into the trunk. These birds are tenacious when it comes to drilling holes in things! Not only are they tenacious, they are powerful. In fact, North America’s largest woodpecker (the Pileated woodpecker) can hit a tree 20 times a second, up to 12,000 times a day, with forces as high as 1,200 times the force of gravity with each hit. That’s roughly the same as hitting a wall with your face at 16 miles an hour – over and over and over again. Ouch. That makes my head hurt just thinking about it!

So how come they don’t hurt themselves?

Woodpeckers are highly adapted to this punishing lifestyle based on the design of their skulls and brains. First, the skull: a woodpecker’s skull is very thick and bony, but the bone itself is fairly spongy. There is also a think layer of cartilage at the bottom of the lower jaw bone that serves as a cushion. This cartilage and bone structure enables to force of the blow to be distributed to the base and back of the skull, rather than the brain.

Next, the brain: a woodpecker’s brain actually has several features that protect it from impact. First, it is small and packaged very tightly inside the skull cavity. Because of its tight packing, the brain does not move much more than the skull does. When a human hits his head, the brain can jostle around within the skull cavity, actually bumping against the bones. That bump causes much of the brain injury associated with a head trauma, such as a concussion. But woodpecker’s brains don’t move that way, so they can’t knock themselves out, get concussions, or incur brain bleeding. Second, there is not a lot of cerebrospinal fluid, either, because there is simply no room for it. This fluid helps transmit shock waves from the skull to the brain, which can also cause injury to the brain. Little fluid – few shock waves. Third, a woodpecker’s brain has a smooth surface, with a high surface area to weight ratio. This is unlike a human brain, which has ridges, folds and bumps all over the surface. We actually have a lot of surface area on our brains! That’s good for thinking, but bad for a head trauma. It means that any impact to the brain is felt over a small surface area. For a woodpecker, a blow to the brain is spread out over a larger surface area, which means that the impact on any given spot is smaller.

Finally, there is another very important fact that helps explain why woodpeckers don’t hurt their heads when they peck – it has to do with their pecking technique. Woodpeckers will always peck at a surface in a straight line, with no side-to-side twisting or torque. This prevents a specific kind of stress on the nerve fibers of the brain called “diffuse axonal injury” or DAI. DAI is one of the most common and dangerous forms of traumatic brain injury. DAI occurs when a sudden deceleration is coupled with some form of rotation, which can twist nerves apart like a lid coming off a jar. A brain impact that occurs straight-on will not cause DAI, because there is no rotational stress being applied to the brain. So it is vital that a woodpecker hit its target dead center and straight on with every hit. And, from all indications, they do!

Incidentally, an Ig Nobel prize was awarded in 2006 in opthamology to Dr. Ivan Schwab and Dr. Phillip R.A. May, for their work on woodpecker head trauma. In particular, they studied why woodpeckers are immune to retinal detachments, brain damage and spinal cord injuries with their repeated head banging. And in addition to the stuff I’ve talked about above, they did learn one additional thing. Woodpeckers always close their eyes with every bang of their beak.

Dr. Schwab did admit, however, that whether they do it to keep their eyeballs in or the wood chips out was an open question.

Roadrunners

My husband and I were fortunate to be able to spend a few days last week visiting family in Palm Desert, California. Palm Desert is a beautiful oasis in Riverside County, a few hours east of Los Angeles. The weather there this time of year is gorgeous – 80 degrees, sunny, light breezes pretty much every day. Perfect weather for sitting out by a pool in the afternoon, which is mostly what we did! One afternoon, while engaged in this extremely pleasant activity, I looked over to the edge of the pool patio, and saw a funny little bird running underneath the shrubs. Lo and behold, it turned out to be a roadrunner.

I’ve never really thought about roadrunners that much (except, of course, for road runner in the Loony Tunes cartoon who always managed to get the best of Wile E. Coyote). But this was a neat looking bird. He had a long neck, a tuft on top of his head, and a very long tail. When he (or maybe a she, I don’t know exactly know what gender it was) walked or ran, his whole body went horizontal – head down, tail stretched out behind him. But when he stopped, his head came up, his tuft poofed out, and his tail rose up behind him. All in all, it was a very cute sight. I decided to investigate roadrunners a little bit more to see what I could find out about them.

A roadrunner is actually a kind of ground cuckoo. It is found in all of the southwestern states, but predominantly in the Mojave, Sonoran, Chihuahuan and south Great Basin deserts. Its prominent features include its tail and head (which I mentioned above), as well as its feet – it has 4 toes, 2 of which point forwards and 2 of which point backwards. The roadrunner can fly, and will do so if threatened or (apparently) if traveling downhill. But because it has a large body and weak wings, it can’t fly very well, so it usually prefers to walk or run. In fact, this little guy can run as fast as 17 to 19 miles per hour. (The fastest human in the world, incidentally, clocks in at around 22 miles per hour. But that’s for a distance of only 100 meters.)

The speed of this bird makes him well adapted to catching and eating other animals. Its diet consists almost exclusively of insects, scorpions, lizards, rodents, and other birds. They have been seen snatching dragonflies or hummingbirds out of air in mid-flight! They will eat fruit that they find on the ground, though, especially in the winter when prey becomes scarce. Roadrunners will even eat rattlesnakes – they are one of the few animals that can do this, actually. To catch this very dangerous snake without getting bit, the roadrunner will dart around, snatch the snake up by the tail, and whip it repeatedly against the ground until it’s dead. And here’s a funny tidbit that I happened across. A roadrunner will eat its prey whole; however, they have been know to catch snakes too big to eat in one sitting. So they will swallow as much as they can, then run around for a while with the rest of the snake dangling out of their mouths until the eaten bit has digested enough to make room for the rest of it! (Yuck.)

Interestingly enough, as long as the food that the roadrunner eats is high enough in moisture, the bird does not even need to drink any additional water. They also have special glands around their eyes that secrete extra salt from their bodies. This makes them very well adapted to living in the desert.

And no, they do not really say “beep beep” whenever they stop. Their vocalizations consist of a much more normal, bird-like cooing or whirring. The "beep beep" is, unfortunately, only in the cartoons.

The marvels of flight

Now that spring is starting to appear, our neighborhood is awash with the song of birds singing in the trees. Every day while waiting for the bus, I see at least a few geese flying overhead on their way south. And the number of robins digging worms in our yard is actually kind of comical. As I watch all of these birds, I am frequently struck by the fact that birds are remarkable fliers. The ease with which they take off, maneuver in the wind, swoop and swoon like acrobats, somehow manage to avoid running into each other, and then land safely on any number of surfaces (trees, roofs, the ground, cars, electrical wires, or the surface of Lake Washington) is remarkable. How do they do it?

Flying is all about having enough upward thrust to overcome to force of gravity pulling an object to the ground. Birds achieve this thrust using their wings in 2 ways – by manipulating air that is already moving (as in gliding) or by moving air themselves (as in flapping).

Gliding is actually relatively simple. When a bird is already airborne, it can glide in much the same way that a hang glider does. For one, they use thermals, trade winds or updrafts. These are piles of air that are rising upwards. The air moving upwards creates a force on the underside of their wings, pushing them up. For another, the shape of the wings gives them upward thrust. As their wings move against the air, they push the air underneath the wings down. This is a force that must be counteracted (according the Newton’s law of every action having an equal and opposite reaction) by an equal and opposite force up. A force pushing up – and voila! Flight.

Okay, so that’s the easy case. What about flapping? How does that work? Well, when a wing flaps, it pushes air in a strong force downwards. This moves the bird up in the air. A curious question, therefore, is why doesn’t the upward stroke of a wing flapping create a force that pushes the bird down? Actually, bird wings are hinged – when the flap down, they are fully extended. But when they move back up, they are folded up, presenting less surface area to push against the wind. You can think about this like the oar on a canoe. If you paddle with the full surface area of the blade pushing against the water, you get a big push. But if you paddle with the blade parallel to the direction of motion, you don’t get much thrust at all. So just imagine a bird wing being like a canoe paddle that pushes air around, instead of water.

Well, it doesn’t sound too complicated, right? If that’s all it takes for flight, why haven’t humans invented self-flying units with retractable wings that we can use to take off, and why don’t we glide into work every day in our personal hang gliders? Well, a bird can fly not only because of the forces its wings can exert on the air, but because its body is uniquely adapted for flight in ways that a human body is not. For example, birds are extremely light. They have extremely strong, hollow bones – strong enough to get the job done, but light enough not to create too much weight to overcome. Birds have feathers, which are capable of trapping and dispersing more air than hair or skin. Birds have highly efficient respiratory systems, which are extremely good at extracting oxygen from the air. In addition, they have extra air sacs next to the lungs, so the animals never run out of breath. This is really important, as it takes a lot of energy (and thus a lot of oxygen) to maintain flight. And birds eat food that is highly energy dense for their body size, which (again) gives them the extra energy they need to carry out this tremendously difficult task.

The human body is all wrong for us to be able to fly on our own. We’re much too heavy, largely because we’re so dense. We don’t have any sort of extra light, fluffy, airy material like feathers to help us move air the way we want to; our arms and hands are neither strong nor big enough to create enough of a downward thrust to move us skyward. Our lungs are perfectly fine for our usual activity on land, but are nowhere near efficient enough for such an aerobically intensive feat as flying. In fact, we just don’t have enough energy, period.

Of course, we have found ways around our limitations as far as flying goes. We’ve built jumbo jets, ultralights, hang gliders, and powered parachutes. So it is possible to get us off of the ground. But if you were to compare the simplicity of a bird flying with all of the ways that we as humans do it?

Frankly, I don’t think it’s much of a contest which one is more elegant. So you can consider this another entry in my list of “ways in which nature is a much better engineer than man.”

(With apologies to all of the engineers I know out there.)

It’s a bird… it’s a plane… it's a squirrel?

Today’s topic is one of those that makes me smile. Say these two little words to me, and I guarantee you that a silly grin will pop to my face. I don’t know why, exactly – it’s just irresistible to me. Want to know what the 2 words are?

Flying squirrels.

I find something irresistibly funny about the idea of squirrels flying loftily through the air. Squirrels! Those little, bushy-tailed sneaks who will do just about anything to get into a bird feeder, who sit and chirp just outside the patio door (tantalizingly out of reach of our cats), who like to play chicken and run across the road right in front of my car, and who have been brazen enough to steal entire grilled cheese sandwiches from picnic tables when my attention has turned. (That’s a true story, by the way.) I guess I find it funny that an animal like that can fly gracefully and elegantly through the sky.

Actually, we must get something straight. Flying squirrels can’t actually fly – they glide. They have a large, loose flap of skin that stretches between their front and back legs. When they jump from a tall tree, this skin stretches out, forming a shape much like a kite. Using the lift provided from these “wings” and their tails as rudders, the squirrels can glide up to 150 feet through the air to land on another tree trunk. The only true flying mammals in the world belong to the order Chiroptera, to which bats belong. Flying squirrels belong to the order Rodentia (yes, they are rodents), the family Sciuridae (meaning squirrel), and the subfamily Pteromyinae (meaning flying squirrels). There are two major subfamilies of flying squirrels – Northern and Southern. These differ in their geographic distribution, forest preference, and subtly in their appearance – for example, Northern flying squirrels tend to be larger than Southern ones.

While the flying squirrel is possibly the most well known mammalian glider, there are other ones, as well. There are several species of gliding possums, including 11 belonging to the family Petauridae. These guys have great names, including the Great-Tailed Triok, Tate’s Triok, Leadbeater’s Possum, the Biak Glider, and the Sugar Glider. There is another species of flying squirrel called the scaly-tailed flying squirrel (an African rodent that’s not actually related to squirrels at all, it just looks like them). There are also 2 species of flying colugos, or lemurs. It’s not a bad list, considering that mammals really do not have the right body shape or structure for flight at all!

What prompted my decision to write about flying squirrels? I came across an article recently in National Geographic about efforts to design a jumpsuit that will allow humans to skydive without a parachute – instead, they’ll glide to safety in the same way a flying squirrel does. It’s called a wingsuit. Actually, wingsuits do currently exist; they have large fabric panels between the arms and legs of the suit that allow the skydiver to maneuver in freefall. However, the current generation of wingsuits are not advanced enough to allow the entire flight to be parachute-free – you still need that for the actual landing. That’s because while the gliding action of the wingsuit slows your vertical speed down dramatically, it translates it into horizontal speed – upwards of 90 miles an hour. That’s plenty of speed to do some damage to your body! Designers are trying to create a wingsuit that will allow the skydiver to manipulate their “wings” at the last minute before landing, slowing their horizontal speed.

Now, the jury’s still out as to whether or not this will actually work. I think we can be certain of one thing, though. Nature still has mankind beat when it comes to creative ways to handle complex problems. What we will only be able to do with extreme effort, these squirrelly little rodents have been doing effortlessly for years. Kind of humbling, don’t you think?