Stories tagged Life Science

Oct
27
2009

Help this little boy find his parents: Sorry. I couldn't find any pictures from Encino Man.
Help this little boy find his parents: Sorry. I couldn't find any pictures from Encino Man.Courtesy cote
It’s a weird suggestion, I know, because you probably give a lot of thought to whom the various cavemen had sex with anyway, regardless of the weather. But give it a little extra thought today. Because it’s nice out, and the dark corners of your brain could use the sunlight.

So, you guys all know that we aren’t the only human species ever to exist, right? The human family tree had other branches before it got to us (take a look at our Human Spark feature for more on that), and there were times when more than one species lived in the same area, and—in all probability—had interactions with each other. Neanderthals, for instance, lived alongside modern humans for many thousands of years in ice age Europe. Keep in mind, “Neanderthal” isn’t just a synonym for “cave-man.” Neanderthals were a distinct species—they had heavier, longer skulls, and thick, strong bodies. The modern humans of ice age Europe would have looked, more or less, like us. And because the two species were living in the same area for so long, it seems pretty likely that they interacted. But did those interactions include, you know, dinner, dancing, and romantic music?

Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Germany says yes, for sure they were having sex.

On one hand, these are sort of fightin’ words. People have suggested that Neanderthals faded into extinction as they interbred with modern humans, but when human DNA was compared with a sequence of Neanderthal DNA, it didn’t look like there was any overlap. That is, if there was any interbreeding, the Neanderthal contributions to our genes have been so diluted with human genes that it doesn’t appear that we have any Neanderthals in our family at all.

On the other hand… Well… I mean… People do all sorts of stuff… We all just want someone to love, right? Or, you know, just think of what a puppy will do to a piece of furniture. And humans and Neanderthals are a lot more similar to each other than puppies and ottomans. Too much? I don’t think so. Look at ligers. Or tigons. Or mules. Similar animals interbreed all the time, but very often they have infertile offspring. And that would explain why we don’t see any Neanderthal genes around today—everybody could have been doing it like it was 2012, but if the offspring couldn’t reproduce it wouldn’t matter to future generations.

Another factor that could explain the lack of genetic overlap (despite Paabo’s certainty of caveman/Neanderthal sexiness) is that our Neanderthal DNA sample just isn’t good enough. Mitochondrial DNA from Neanderthals doesn’t show up in modern humans, and while that’s an incredibly valuable genetic marker, it only makes up a tiny fraction of an organism’s total DNA. The Neanderthal genome hasn’t been completely sequenced yet, and that’s what Paabo means to do. Once we can fully compare the genomes, we can see if the two species became at all mixed.

Because they were definitely doing it.

Oct
23
2009

Stay sober, stay stimulated: Stay off sensory deprivation! Oh... wait... that wasn't the point of the study?
Stay sober, stay stimulated: Stay off sensory deprivation! Oh... wait... that wasn't the point of the study?Courtesy mikebaird
Stay in school, little dudes. That’s important. Also, stay off drugs. That’s also important.

Why? Because school embiggens your brain. And because drugs interfere with the brain embiggening process. Your uppers, your downers, your sliders, your narcotics, your kool-aid/cough syrup concoctions, your hallucinogens… they’re all dangerous, they will all keep you from focusing your brainwaves and chi and stuff.

But it’s easy avoiding those effects, right? The secret is to just not do drugs, right?

Wrong! Just 15 minutes of sensory deprivation can trigger hallucination! That’s just you and your brain, alone together in a totally quiet and dark room, making each other craaaaazy!

200 participants were given a questionnaire to determine how prone each person was to hallucinations. 9 of the highest scorers (that is, they had a high propensity for hallucination) and 10 of the lowest scorers (the least likely to hallucinate) were then (after volunteering) placed individually into an anechoic chamber. The anechoic chamber is build to muffle as much external sound as possible, and there’s no light inside, so once the participants were shut inside, they were in complete darkness and silence for the 15-minute duration of the test.

The study found:

“Of the nine volunteers who had high scores on the first questionnaire, almost all reported experiencing something "very special or important" while inside the chamber. Six saw objects that were not there, five had hallucinations of faces, four reported a heightened sense of smell, and two felt there was an evil presence in the chamber with them.”

Even the participants who scored low on the first test experienced hallucinations and delusions, although not as heavily as the first group.

The research seems to support the idea that hallucinations (or some hallucinations) are caused by the brain misidentifying its own thoughts and activity as something that comes from outside the body. So… you bring your crazy with you into the sensory deprivation chamber, I guess.

You hear that kids? If you’re not careful, and, like, accidentally fall into a sensory depravation chamber, your straightedge lifestyle will suddenly count for nothing! And you won’t get into your favorite ivy-league college, you little junky, you. So, whatever you do, stay stimulated! And if you ever do get trapped in an anechoic chamber, try to create your own sensory experiences until help arrives. I can't recommend whistling, because you’ll need your mouth for the arm-licking that I do recommend. But I think you should be able to hum and lick your arm at the same time, so do that. And, if you’re able, fart like crazy. With all this stimuli, you should be able to maintain some level of sobriety until a fireman axes the box open to find you sanely humming, licking your arm, and farting.

The more you know. You know?

Oct
20
2009

The first 2009 H1N1 vaccines are starting to arrive in Minnesota. So I'm wondering, will you be vaccinated? How about your kids? A national study out of the University of Michigan says only 40% of parents plan to get their kids vaccinated. Why? I think Michael Specter sums it up best in a New Yorker article:

In fact, the new H1N1 virus is similar to seasonal flu in its severity. In the United States, influenza regularly ranks among the ten leading causes of death, infecting up to twenty per cent of the population. It kills roughly thirty-five thousand Americans every year and sends hundreds of thousands to the hospital. Even relatively mild pandemics, like those of 1957 and 1968, have been health-care disasters: the first killed two million people and the second a million.

We are more fortunate than our predecessors, though. Scientists produced a vaccine rapidly; it will be available within weeks. And, though this H1N1 virus is novel, the vaccine is not. It was made and tested in exactly the same way that flu vaccines are always made and tested. Had this strain of flu emerged just a few months earlier, there would not have been any need for two vaccines this year; 2009 H1N1 would simply have been included as one of the components in the annual vaccine.

Meanwhile, the virus has now appeared in a hundred and ninety-one countries. It has killed almost four thousand people and infected millions of others. The risks are clear and so are the facts. But, while scientists and public-health officials have dealt effectively with the disease, they increasingly confront a different kind of contagion: the spurious alarms spread by those who would make us fear vaccines more than the illnesses they prevent.

I'm planning on getting the vaccine if I can and I'll make sure my kids get the vaccine. It is all about the risk vs. benefit for me. What are your plans and why?

Oct
13
2009

A friendly bear provides heat for the benches: A nice change from what bears sometimes do, right?
A friendly bear provides heat for the benches: A nice change from what bears sometimes do, right?Courtesy HolgerE
Since the dawn of humanity, we Homo sapiens sapiens have lived in fear of non-human animals, hiding in shadows, flinching at every sudden movement, lest it be the leaping of a huge, saber-toothed cat, a swipe of the massive paw of a bear, or, like, some sort of big snake.

Defenseless, we have eked out our existence in the puddles and dusty corners of the world, powerless against the animal threat.

Until now!

We’ve finally figured out how to destroy animals: with fire!

Check it out: on the 12th there was a news story about a Jordanian shepherd inadvertently witnessed the spontaneous combustion of a flock of sheep, and by today I found a story about a Swedish facility burning spare rabbits to heat the nearby town. (Those Scandinavians are so green!

We’re taking back the planet!

For anyone interested (not sure why you would be), here’s the rest of the story: The burning sheep thing had to do with a local waste treatment facility leaking methane and “organic material” into the ground. The soil became saturated, and when sparks from a grassfire hit the fumes… boom! Roast mutton. Also, this was probably a horrible, horrible thing to see.

The rabbit burning, amazingly, is slightly controversial. Stockholm’s parks are over populated with rabbits, so thousands of them are culled (killed) each year. Last year alone, over six thousand of the rabbits were frozen and trucked to a heat producing facility in Karlskoga, in central Sweden, where they were burned to produce heat for the province of Varmland. How… practical. Some folks have claimed that pet bunnies (or at leat the descendants of released pet bunnies) have been rounded up as well, for chewing on the flowers and shrubs in the parks of Stockholm. They aren’t happy about thee bunny burning, and suggest that a system of shelters be arranged for captured (living) rabbits. Tell that to the shivering people a Varmland. Tell them you’re taking their cheap rabbit-heat.

Oct
04
2009

Antennas key to navigating during migration

Monarch migration: The antenna is vital to navigating.
Monarch migration: The antenna is vital to navigating.Courtesy L-T-L

Ever wonder how monarch butterflies navigate. They use the sun you might say. The sun is constantly moving, though. Well, maybe a built in clock helps. How important are the eyes compared to the antennas?

To figure out what was important scientists dipped some antennas in clear varnish and some in black paint. The ones with clear varnish had no trouble navigating. The ones with black paint covering their antennas could not.

That not only showed the antennas were sensing light for navigating, it also showed that the sense of smell isn't involved in finding the way, since both paints blocked that ability. USA Today

Learn more monarch migration

The study was led by Dr. Steven M. Reppert, chairman of neurobiology at the University of Massachusetts Medical School. I urge you to visit his faculty web page which explains how his team is using anatomical, cellular, molecular, electrophysiological, genetic and behavioral approaches to more fully understand the biological basis of monarch butterfly (Danaus plexippus) migration.
The incredible detail and depth of their research made me appreciate how understanding one little thing like butterfly migration can lead to better understanding how complex things like the human brain works. This recent paper published in science was titled, Antennal Circadian Clocks Coordinate Sun Compass Orientation in Migratory Monarch Butterflies.

Sep
24
2009

The golden web of an orb-weaver: Little does this spider suspect that it is about to be captured and milked by the clinically insane.
The golden web of an orb-weaver: Little does this spider suspect that it is about to be captured and milked by the clinically insane.Courtesy Tai Po Kau Nature Reserve
After decades of frustration and failure, mankind’s dream of weaving a blanket entirely from the stuff of nightmares has become a reality.

For centuries, the very possibility of creating fabric from nightmares was considered little more than a fever dream, and the criminally insane resigned themselves to nightmare cloth substitutes, like hammered-flat baby rabbits, and prison toilet paper. Inventive though these are, like soymilk, they fooled no one.

Then, at the end of the 19th century, reports began to filter from Africa that a French missionary in Madagascar, exploring the dark peaks of his own madness, was creating fabrics of almost pure nightmare.

The missionary had supposedly created a spider-milking machine, into which he was placing massive Golden orb-weaver spiders, collected in their hundreds by local young girls. (Having little girls collect the spiders made the nightmare purer, but was not strictly necessary. Leave it to a missionary for such meticulous detail.)

The spiders were restrained in “a sort of stocks,” and then the beginnings of a strand of silk was coaxed from their abdomens and attached to a hand cranked wheel, at which point several hundred yards of the orb-weavers’ characteristically golden silk could be withdrawn from each spider. When the creatures could yield no more silk, they were released, apparently unharmed, back into the wild, where they would regenerate their webbing material after several days. The spooled spider silk could then be woven like any other material… but scarier.

Seemingly too “good” to be true, the missionary’s experiments were never replicated, and generations of madmen made do with sheets of dried bat saliva and mortuary blankets. Until now.

A “textile expert” and a visionary in what liberal arts colleges refer to as “insane studies,” Simon Peers and Nicholas Godley, recreated the missionary’s spider-milking machine, and after four years and one million spiders they have created an indestructible golden blanket, woven of pure nightmares.

The madmen discovered that while a single spider might produce a strand of silk up to 400 meters long, the material is, of course, exceptionally light. It took approximately 14,000 spiders to produce a single once of silk. The final 11 foot by 4 foot piece of fabric weighed about 2.4 pounds (~38 oz). So many, many spiders were involved, and lots of time. To help pass the long months of spider-milking, the artists whispered their secrets into mouse holes, and built razor blade houses.

The final intricately patterned textile has a rich, naturally golden color—the golden orb-weaver is named for the color of its silk, which attracts pollen-seeking insects in sunlight, and blends with background foliage in shadow. The spiders can adjust the exact tone of their webbing based on ambient light levels and color, so this textile has a unique shade based on how a million spiders perceived the room containing the tiny spider stocks.

The fabric is also exceptionally strong. Spider silk can stretch to 140% without breaking, and has tensile strength comparable to or exceeding that of modern fabrics like Kevlar, used for bullet-proof body armor. The complex protein structure that gives spider silk its strength has also makes it very difficult to reproduce artificially (that is, it hasn’t been done). Attempts have been made to insert the gene for spider silk protein production into goats, which then produce the protein in their milk, if not actual fibers. Unlike silk moths, spiders aren’t suited for mass production of silk, as they tend to kill and eat each other. And so it takes a madman, obsessed with drawing the secreted material for trapping prey from a hand-sized, venomous arachnid predator, to obtain enough spider silk to actually make something form it.

Despite civilization’s unwritten, yet long-standing rules against allowing madmen to have golden bulletproof cloaks, there is little to be done in this situation, seeing as how they made it themselves. Out of nightmares.

The textile is now on display at the American Museum of Natural History. (And, again, a photo of it can be seen here.

Sep
16
2009

Many people wonder what happens to your hair and nail after death. Does your hair and nails still grow by itself or does it just stop right after death? There was an argument saying that your nails and hair still do grow after death, while others say they stop growing after death. What is the answer to this situation?

Well the answer is easy. No, your hair and nails don't still grow after death. As you die, your body dehydrates. This causes the skin and organs to shrink in size (remember your body is made out of 70% of water) but not the hair and nails. This gives the appearance of growth, but it's really the skin being pulled back. The reason the hair and nails don't shrink is because while the rest of the body does, it's already dead. The only part of hair that is alive is the follicle (a small spherical group of cells) and when that dies, you go bald over times as your hair falls out. And since because your hair grows do to protein and oil, there isn't any living cells to carry out this function so it would just be long gone. Hairs and nails don't shrink during funeral time is because they used some moisturizing cream on their body and hair, this stops it from shrinking. And if they didn’t then your hair would have fallen out and you would go bald.

When I first heard about this situation about hair and nails still growing after death, I was shock. And I was like no way your hair and nails still grow after death. I just had to research about the topic and find answers to this. When I did found out that the answer was no, I was like ok this is a better understanding. How can your hair and nails still grow when your body is already shut down? I am glad that I found the answer to this. Now I know the truth.

Sep
11
2009

An old Japanese guy: His secret? Hamburgers. Lots of hamburgers.
An old Japanese guy: His secret? Hamburgers. Lots of hamburgers.Courtesy isado
You heard it here first, folks, unless you heard it somewhere else already: There are a ton of really old people in Japan. And when I say really old, I mean older than 100 years old. And when I say a ton of people, I mean more than 40,000 people. Considering that the average weight for a Japanese centenarian (people over 100) is about 110-118 pounds, “a ton” is really way too small an amount. There are actually about 2,280 tons of really old people in Japan.

Although the US still blows Japan out of the water with the number of 100+ people in the country (We’re creeping up on 100,000. USA! USA!), your chances of living to be a super old dude or lady are much higher if you’ve lived your life in Japan. And people on the Japanese island of Okinawa are five times more likely to live to be 100 than even the rest of the Japanese population.

Plenty of research has been done on centenarians to isolate what factors might have allowed them to live for so long, and… the results aren’t super surprising. Certain genes are associated with long life, but so are certain diets and certain lifestyles. Basically, if you want to live to be one hundred, you should walk a lot, think a lot, poop a lot, don’t eat a lot, and hope your parents live to be one hundred. Or you could just start counting your age in dog years.

Sep
10
2009

Pshhhheeeewww!: Science everywhere!
Pshhhheeeewww!: Science everywhere!Courtesy SiamEye
I don’t even know where to begin today! All I can think is “OMG!!!!” And each exclamation point I think is like a blood vessel bursting in my brain!

OMG pop pop pop

So why is this a day of excitement, instead of quiet family tragedy? Because the biggest explosions today aren’t happening in little tubes in my head, they’re happening in the world of science! (I don’t consider the physiology of my head to be science. More like magic. Or trial and error.) I just don’t know what to do with all this science.

See, unlike your average Friday Extravaganza, a Thursday Explosion has no focus; it’s just kind of all over the place. A mess! There are all these stories, but we really have to stretch to fit them into a single post… so the loose theme of this explosion will, fittingly, be “flying things.” Am I not helping? Just wait, you’ll see.

Normal mouse becomes flying mouse, doesn’t care!
Check it out: a baby mouse was put into a little chamber and subjected to an intense magnetic field. What happened? All the water in the mouse’s body was levitated. And because those squishy little mice are so full of water, the mouse itself levitated along with the water.

Unfortunately, the first mouse wasn’t quite ready for life as an aviator, and upon levitation, he began to, as scientists say, “flip his Schmidt.” Lil’ mousey started kicking, and spinning, and with minimal resistance in the chamber, he started spinning faster and faster. He was removed from the machine, and put wherever little mice go to relax. Subsequent floating mice were given a mild sedative before flying (pretty much the same thing my mom does), and they seemed cool with it. Now and again the floating mice would drift out of the region of the magnetic field, but upon falling back into it they’d float right back up. After remaining in a levitating state for several hours, the mice got used to it, and even ate and drank normally. Afterwards, the mice had no apparent ill-effects from the experiment (rats had previously been made to live in non-levitating magnetic fields for 10 weeks, and they seemed fine too.)

Aside from the excitement normally associated with floating mice, the experiment is promising in that it may be a useful way to study the effects of long term exposure to microgravity without bringing a subject to space.
pop pop pop

Great tits are dangerous if you’re a sleepy bat!

It’s true! Forget everything you thought you knew about great tits and get schooled once again, my friends, for great tits are killers!

I’m not talking about the senseless murder of bugs, either—everybody already knew that great tits are primarily insectivores. A population of great tits in Hungary have been observed hunting bats!

As fun as it is to keep writing “great tits” with no explanation, I suppose we should be clear that great tits are a type of song bird common in Europe and Asia. Little, bat-hunting songbirds.

Meat eating great tits had been reported in other parts of Europe, but it was thought that those individuals had only consumed already-dead animals. The tits of Hungary were actually observed flying into bat caves, where they would capture tiny, hibernating pipistrelle bats and drag them out of the cave to devour them alive. It even appeared that the birds had learned to listen for the bats’ disturbed squeaking (or, as I like to think of it, their horrified shrieking)—when the same noise (which is too high for humans to hear) was played back for captured tits, 80% of the birds became interested (read: bloodthirsty) at the sound.

If it really is just the Hungarian population that engages in this behavior, the situation also brings up the possibility of culture in the birds. That is, if this isn’t some sort of innate behavior, but something learned and taught, and passed through generations that way, it could be considered culture. Amazing! Great tits are cultured!

pop pop pop

Flying velociraptors!

Well, not so much flying as falling. But falling with purpose. (What was it Buzz Lightyear said? Oh yeah, “I’m so lonely all the time.”)

We all know about how awesome raptors are. I think it’s part of kindergarten curriculum now, just between how not to accidentally poison yourself, and why you shouldn’t swear and hit. Well, I remember reading a news item a couple years ago about how some paleontologists were thinking that raptors’ famous giant toe claws may not have been for disemboweling their prey. Instead, the scientists proposed, raptors would lodge the massive claw into the skin of their prey with a kick, and then use it to hang on to the unlucky animal while the raptor went bite-crazy. The researchers had made a simulation of a raptor claw, and found that it could easily puncture thick skin and flesh, it didn’t seem to be sharp enough to actually cut the skin. (Cutting is necessary for a good disemboweling.) One might argue over the strength and sharpness of raptor claws, considering that the fossilized bone claws we see in museums would have been covered with a tough, horny substance, which did not fossilize, but whatever—the new scenario was still pretty cool.

Now, the same group of paleontologists is proposing that raptor claws were also well suited to tree climbing. Raptors could have waited on overhanging limbs, and then pounced on their prey from above. Pretty neat! The researchers point out that the microraptor a tiny relative of the velociraptor, had feathered limbs to help it glide down from high places, so it’s not a stretch to think that its cousins were comfortable in trees too. “The leg and tail musculature,” one scientist says, “show that these animals are adapted for climbing rather than running.”

I’ll take his word for it, I guess, but I do have some questions on that point. There’s a dromaeosaur (it looks a lot like a velociraptor) skeleton here at the museum, and I seem to remember that its tale was supposed to be very stiff—it has these cartilage rods running the length of the tail to keep it rigid. I feel like a long, stiff tail would be a pain in the butt up in a tree. It’s not the sort of thing arboreal animals invest in these days. Also, I wonder what sort of vegetation was around in the areas raptors lived. Plenty of big trees with good, raptor-supporting limbs? (I’m not implying that there weren’t, I’m just curious.)

The researchers do acknowledge that tree climbing wouldn’t have been every raptor’s cup of tea, however. Species like the utahraptor, weighing many hundreds of pounds, and measuring about 20 feet in length would have been “hard put to find a tree they could climb.”

pop pop pop

Pretty neat stuff, huh? Explosions usually are. But you see now why I couldn’t wait for three posts to get it all out there.

Sep
04
2009

It's giant puffball time
It's giant puffball timeCourtesy ARTiFactor
The first time I saw giant puffball mushrooms in the woods I thought they were gallon sized plastic jugs. One that I saw behind the Tea House in Como Park's Japanese Garden looked just like a soccer ball.

Giant puffballs are edible

I slice them like bread and fry them on a pancake griddle. For flavor I use various seasonings like cinnamon and sugar or Cajun spices.

My wife used to see them along the State Fair ground fences (North side).

If they are yellow inside, it is too late to eat them. The one in the picture was traded in at our Collector's Corner on Wednesday. I sliced it once to see if it was good. Today I sliced it again and saw the yellow color. Yuck! Eat 'em while they are fresh.