Stories tagged Life Science
Blue, blue, my ears are blue.: The blue morpho butterfly hears through ears on its wings.
Courtesy William Warby
The blue morpho does. Scientists have found that this large butterfly of Central and South America has ears on its wings. These primitive ears can distinguish between the high-frequency sound of a bid singing, and the low-frequency sound of a bird flapping its wings. A singing bird is a sitting bird, and thus no threat to the morpho, but a flying bird could be attacking, and detecting those sounds tells the butterfly when to beat a slow, erratic retreat.
(Wait a minute…Blue Morpho…wasn’t he a character in Yellow Submarine Reloaded?)
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Richard Lenski (top) and Jeffrey Barrick view bacteria cultures in Lenski's lab.: They have watched the bacteria's DNA evolve over 40,000 generations.
Courtesy Michigan State University / photo by G.L. Kohuth
Sometimes you’ll hear people cast doubts on evolution because no one has ever seen it happen. As if that’s some sort of great insight. No one has eve “seen” atomic fusion, either, but the fact that the Sun was shining this morning is pretty strong evidence that, yep, it happens. No one has ever “seen” gravity. Seen gravity’s effects, sure. But seen gravity itself? Like Ms. Ono once asked, Who Has Seen The Wind?
Evolution used to be in the same boat. The effects of evolution are visible everywhere, in every cell of every living thing on the planet. But seeing the actual process of evolution? That was another matter.
Until now. Scientists at Michigan State University (go Spartans!) have been growing bacteria in bottles for the past 21 years. Every so often, they would freeze a sample for later study. Well, “later” is now. DNA sequencing and computer analysis have advanced to the state where they can readily map the genome of each sample. And guess what? The bugs evolved exactly as evolution says they should. Mutations in the genome pop up at random intervals. Mutations that help the bug survive—like make more efficient use of food, or fend off disease—get passed on to future generations, and eventually spread through the entire colony.
Twenty-one years may not seem like enough time for a species to change. But, as Mia Sorvino said in the truly awful 1997 movie Mimic, think generations, not time. In the two decades of study, the little bacteria went through 40 thousand generations—the equivalent of roughly 800,000 years in human terms. Plenty of opportunity for evolution to do it’s thang.
And the experiment continues. Understanding mutations in bacteria might help us understand the mutations that lead to some forms of cancer. In recent generations, the rate of mutation has increased; the scientists would like to know why.
Richard Lenski, the scientist heading up the research, has put together a video explaining his work.
Deer Rumen: Opening up a deer's rumen.
Courtesy Kirk MonaEver wondered what's inside the stomach of a deer? For those not afraid of some graphic photos, the Twin Cities Naturalist Blog. has posted photos and descriptions of the four parts of a deer's stomach. Here's a quick overview.
- The Rumen is a fermentation and storage vat. Micro-organisms break down a lot of food in the Rumen so it can be absorbed by the deer but it does not physically break down the food with acid like a human stomach.
- The Reticulum is basically a filter that allows small particles to pass to the Omasum.
- The Omasum acts like a sponge that draws off excess water before food is passed to the next step.
- The Abomasum works like your stomach to break down food with acid so nutrients can be absorbed.
You can see all the photos and read more at Twin Cities Naturalist.
It's smiling!: But wait until it gets bitten in half.
Courtesy PterantulaNot much to say here other than… Holy Smokes! Check his out: a huge shark bitten in half by an even huger shark!
Shark fishermen in Queensland Australia pulled a ten-foot great white from a baited drum line to discover that the shark had been nearly bitten in half by an even bigger shark. Again, take a look. And the 10-footer was still alive when they pulled it into the boat. (Yowza.)
The think that the larger shark was also a great white, and that it might be as large as 20 feet long. A shark that size weighs about 4,400 pounds. There’s been some debate regarding the maximum size of a great white, but 20 feet is probably about as large as they can get. (In the late 19th century and early 20th century, there were reports of sharks caught that measured over 30 feet, but reexamination indicated that they were probably significantly shorter.) At any rate, the shark in Jaws (I think its name was Eustace) was supposed to be 25 feet long, so 20 feet is nothing to sneeze at. Unless huge sharks make you sneeze.
Happy shark attack Tuesday!
Help this little boy find his parents: Sorry. I couldn't find any pictures from Encino Man.
Courtesy coteIt’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.
Stay sober, stay stimulated: Stay off sensory deprivation! Oh... wait... that wasn't the point of the study?
Courtesy mikebairdStay 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?
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?
Archaeopteryx more dinosaur than bird
in Earth and Space Science, Life Science, Diversity of Organisms, and Biological Populations Change Over Time
Archaeopteryx: Detail of the Thermopolis Specimen
Courtesy Mark RyanWhen the first Archaeopteryx skeleton came to light in 1861 just two years after the publication of Charles Darwin’s On the Origin of Species, it was hailed as not only the earliest known bird but also as proof of evolution. The rare specimen (known as the London specimen) appeared to be somewhat of a chimera of both dinosaurian and bird features. Thomas Huxley, a fierce proponent of Darwin’s work, even suggested that birds were the descendents of small meat-eating dinosaurs. It took more than a century for the idea to become widely accepted. Today most paleontologists divide dinosaurs into two groups: avian dinosaurs (birds) and non-avian dinosaurs, the branch that died out at the end of the Cretaceous.
"For a long time, Archaeopteryx was considered the archetypical bird primarily because it had feathers, although it retained typical dinosaur features like a long tail and teeth,” said Mark Norell, Chair of the Division of Paleontology at the American Museum of Natural History. “But the discovery of classical bird features like feathers and wishbones have recently been found in many non-avian dinosaurs blurring the line of what constitutes a bird."
Now, a new study by Norell and co-author Gregory Erickson, a vertebrate paleontologist at Florida State University, shows that 150 million year-old Archaeopteryx (Greek for “ancient wing”) may have been much more like a non-avian dinosaur than a bird (avian dinosaur), at least in its bone structure and growth rate.
"Dinosaurs had a very different metabolism from today's birds,” Erickson said. “It would take years for individuals to mature, and we found evidence for this same pattern in Archaeopteryx and its closest relatives.”
For their research, the team removed tiny, 250-micron slivers of bone from the remains of several Archaeopteryx fossils, and from the bones of primitive but younger bird fossils (Jeholornis prima and Sapeornis chaochengensi, and Confuciornis sanctus) found recently in China. They also examined the bone structure of closely related non-avian dinosaurs such as Velociraptor mongoliensis.
Those samples from the Archaeopteryxes showed high bone-density, annual growth lines (a reptilian trait), and very small blood vessels similar to the bones sampled from the non-avian dinosaurs. The location of bone cells also appeared flattened and parallel – more like that of a velociraptor – and much different from the hollow, vascularized (i.e. filled with blood vessels), rapid growing bones found in younger-aged bird fossils, and most birds today. (Flightless birds such as ostriches and penguins have solid bones.)
"Although the genealogy of birds is well understood, the genesis of modern bird biology has been a huge mystery,” Norell said. “We knew that they are a kind of dinosaur, but we now know that the transition into true birds—physiologically and metabolically—happened well after Archaeopteryx."
What this implies is that Archaeopteryx was more of a dinosaur than it was a bird – at least in its metabolism and how fast it matured – and that the traits considered necessary for flight – such as light, hollow bone structure – evolved from a dinosaur body-plan sometime after Archaeopteryx.
"We show that avian flight was achieved with the physiology of a dinosaur," Erickson said.
The study can be found in a recent edition of the online journal PLoS ONE.
ScienceDaily story
Gregory Erickson’s Dinosaur Growth page
More info and photos about Archaeopteryx
Marie Carmichael Stopes
Courtesy Wikimedia CommonsToday is the birthday of Marie Carmichael Stopes, paleobotanist, poet and novelist, and family planning pioneer. Born in Edinburgh in 1880, as a young girl Stopes planned out her adult life in three stages: twenty years would be spent in science, twenty in social projects, and twenty writing poetry. And that’s exactly what she did. Stopes’s accomplishments are remarkable even though they often put her at odds with the institutions and social mores of her time. At 18, she won a science scholarship and attended University College in London receiving early honors in both botany and geology. After graduate studies in Munich she earned her Ph.D in paleobotany. She lectured on the subject at the University of Manchester for seven years. She also published the book Botany: the modern study of plants, and did research on the history of angiosperms and the composition of coal. This won her a grant from the British Royal Society that led to her collecting and studying fossil plants abroad in Japan for eighteen months. All this was done at a time when a woman’s place was definitely thought to be in the home. As an early proponent of birth control and women’s rights, Stopes established Britain’s first birth control clinic in 1921, and authored several books on the subjects of marriage and parenthood. Her best known work, Married Love : A New Contribution to the Solution of the Sex Difficulties, was written while – and probably because - she was still a virgin (she had been married but her husband proved impotent, and their short-lived marriage was supposedly unconsummated). Her second marriage produced one child, a son named Harry born in 1924. As she raised him, she continued her campaign for family planning, writing extensively on the subject. Stopes also founded the Portland Museum in Dorset in 1930, and wrote and published novels, plays, and poems including Love's Creation (1928) and Love Songs for Young Lovers (1938), although these writings never matched the attention garnered by her science and social writings. Marie Stopes died of cancer in 1958 a few days short of her 78th birthday.
LINKS
Marie Stopes, Scientist and Reformer
More about Marie Stopes on BBC.com
Additional info on Marie Stopes
Marie Stopes International organization
A friendly bear provides heat for the benches: A nice change from what bears sometimes do, right?
Courtesy HolgerESince 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.
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