Scientific American has an awesome contest going on right now. They're challenging you to make a video explaining some part, process, or system in the human body using eight objects: Yourself, a writing surface, a writing implement, rubber bands, paper clips, string, cups , and balls. You have to use all eight items. You can't use anything else.
You can read the full instructions and rules online. And check out the sample video, made by Scientific American interns Isha Soni and Mollie Bloudoff-Indelicato.
Bonus: The first 100 qualified entries all get a free digital subscription to Sci Am.
Via Bora Zivkovik
Last week, an American and a Russian — Scott Kelly and Mikhail Kornienko — were selected to spend a year living continuously in space, aboard the International Space Station. Only four other people have done this before. All them were Russian, so Scott Kelly is going to break the American record for time spent in space.
The mission won't start until 2015, and it's part of a much longer term goal — sending people to Mars. We know that spending time in space does take a toll on the human body. For instance, hanging out without gravity means you aren't using your muscles, even the ones that you'd use to support your own weight on Earth. Without use, muscles deteriorate over time. Bone density also drops. Basically, after a few months in space, astronauts return to Earth as weak as little kittens. Which is, to say the least, a less than ideal situation for any future Mars explorers.
Having Kelly and Kornienko stay up for a year will give scientists more data on what happens to the human body in space, give them a chance to test out preventative treatments that could keep astronauts stronger, and allows them to see how the amount of time spent in space affects the amount of time it takes to physically recover from the trip. As an extra research bonus, Kelly is the identical twin brother of Mark Kelly, the astronaut married to former congresswoman Gabrielle Giffords. Which means that there will be a built-in control to compare Kelly to when he comes back from his mission.
In honor of that upcoming experiment, here's an old video that will give you an idea of what we knew (and didn't know) back at the dawn of the space age. Science in Action was a TV show produced by the California Academy of Sciences. In this 1956 episode, they explore the then-still-theoretical physiology of space travel ... with a special guest appearance by Chuck Yeager!
Imagine an apatosaurus with a long, elephant-like snout. Plenty of people have. That's because the nostril placement on sauropod dinosaurs is, in some ways, remarkably similar to that of trunked animals that live today. In both cases, the nostrils are large, and they're located up around what we'd call the forehead, kind of smack between the eyes.
On the one hand, this is one of those things that it's really hard to ever know for certain. We don't have preserved soft tissue, so when we make models of what dinosaurs might have looked like we're really going on clues from the bones and comparisons to living animals with similar bone structure. Because of that, it is somewhat reasonable to suggest that hey, maybe, sauropods really did look like grumpy diplodocus in the image above. It's fun to speculate.
But not all speculations are created equal. In a fascinating post at the Tetrapod Zoology blog, Darren Naish explains why a superficial similarity to trunked animals isn't enough to counteract the much-more prevalent evidence against sauropod trunks. One of the more interesting lines of evidence he points out is the fact that dinosaurs apparently lacked the facial which form the trunk in living animals. We know this partly because muscles leave their signature on bone, and Naish says there's no evidence sauropods had the right facial muscles. It's further bolstered by the fact that the animals most closely related to sauropods don't have those facial muscles, either.
Naish's piece reminds me of the last time we talked about sauropod biology here. That, too, dealt with the fact that superficial similarities aren't enough to infer that two animals must have identical biology. Only, in that case, we were talking about the differences between the long necks of giraffes and the long necks of sauropods.
Here's a big difference between nature and a natural history museum: In the wild, when you find a skeleton of anything, it's seldom arranged in a neat, orderly, anatomically correct manner. Even if an animal dies in captivity, nature won't just conveniently produce a skeleton suitable for mounting.
So how do museums get the perfect skeletal specimens that you see behind glass?
The answer: Lots and lots and lots of tedious work. Plus the assistance of a few thousand flesh-eating bugs.
This video from the University of Michigan traces the creation of a bat skeleton, from a fleshy dead bat in a jar, to a neat, little set of bones in a display case. It's painstaking (and moderately disgusting) work. Sort of like building model cars, if the Ford Mustang had realistic organ tissue.
Thanks to Neil Shurley!
This hummingbird is sleeping in a specialized research container connected to a machine that measures how much oxygen it is breathing. According to forrestertr7, who posted the video to YouTube, this experiment was part of research aimed at understanding the differences between the metabolism of hummingbirds and that of larger species. After its nap, the hummingbird was released back into the wild.
But what about the snoring? Does the hummingbird really need a tiny, little beak strip, or what? I asked science blogger Joe Hanson, who posted this video to Twitter earlier today, and he did some research. Turns out, it's not totally unreasonable to call that adorable little wheeze a "snore". But, at the same time, hummingbirds have very different biology than we do. A snore for them isn't the same as a snore for us.
Hummingbirds have incredibly high metabolic needs. To do all that buzzing around and to keep their tiny bodies warm, they eat the human equivalent of a refrigerator full of food every day, mostly in the form of high-energy nectar and fatty bugs. Because of their small size, they also lose a lot of body heat to the air. In order to preserve energy on cool nights, they have the ability to enter a daily, miniature hibernation called torpor.
...Just before morning, their natural circadian rhythms kick in and they start to thaw out, like heating a car engine on a cold day. What we see in the video is probably a bird coming out of torpor (which is what the scientists in the video were studying), starting to breathe in more oxygen to raise its body temperature, and making that adorable snoring noise.
Read the full story at Joe Hanson's blog, It's Okay To Be Smart
The science behind the story of how Reddit saved yet another life.Read the rest
Come on. It's for science.
In fact, it's meant to help people.
Researchers at Simon Fraser University in Burnaby, British Columbia, Canada, put a dead pig in a shark-proof (and octopus-proof, as you'll see) cage and stuck it in the ocean in order to learn more about how human remains decompose underwater. That knowledge will help forensic scientists interpret crime scenes.
Most of the work is done by maggots known as sea lice, but towards the end, after the maggots have eaten the good bits, you can watch some fat, red shrimp move in to pick apart the cartilage.
Via Deep Sea News
Proteins are made up of chains of amino acids, folded and twisted in on themselves to make incredibly complex shapes.
The human brain, it has been said, is kind of a pattern-finding machine — prone to spotting faces on the moon, fat bunnies in the clouds, and Jesus on slices of toast.
When the two meet, you get Protein Art. May K., a Russian-born artist who lives in Germany, takes actual protein structures, sees the other things those structures seem to look an awful lot like, and then draws cartoons based on the resulting apophenia.
For instance, take a look at the protein structure above. After the jump, you can see the picture that May K. saw in its folds.
Read the rest
Fuzzyatelin, a field biologist, offers graphic and compelling advice on keeping your feet dry during your fieldwork.
1) For frak’s sake, DRY OUT YOUR SOCKS. Put them over the fan over night so that you have 5 precious, precious moments of dryness before stepping out that door into the rain again…
2) Air everything out. For real. I mean everything. If you have electricity, lay in front of a fan in the buff for at least two hours every evening. You think I’m joking… but:
3) When your feet start to bleed - and boy, will they ever - don’t panic. The hole that appears to be eating its way into the space between your 4th and 5th toes on your right foot won’t go any deeper than a full centimeter (you know this because you stuck your finger inside of it and then measured the extent of the bloody seepage on your pinkie finger… the hole is that wide and deep).
4) Ditch the hat. Ditch the hat. Ditch the - oh. Now it’s on your scalp.
It gets worse.
The MouSensor is a lab mouse genetically-engineered to sniff out land mines. Mice have already been trained to find explosives by scent but according to Hunter College biologist Charlotte D'Hulst, the MouSensor is ultra sensitive to the odor of TNT. From The Guardian:
Given its extreme sensitivity to TNT, the mouse would probably have some sort of seizure when it sniffed explosives, said D'Hulst, because so many neurons in its olfactory bulb would be firing at once. And that seizure might be detectable by some device implanted into the mouse.
"We are thinking along the lines of implanting a chip under the skin of these animals that would wirelessly report back to a computer when the animal's behaviour is changing upon being triggered by a TNT landmine," said D'Hulst. Once the location of a landmine had been identified, a bomb-disposal expert could go in and neutralise it in the normal way. The mouse itself would be safe from the landmine, since it would be too small to trigger an explosion.
Remember arsenic life? In 2010 NASA researchers thought they'd found evidence that certain bacteria could use arsenic in their DNA where all other forms of life on Earth use phosphate. Then it turned out their research was really flawed. Then it turned out they were wrong. In general, there was a to-do.
Fast forward to this month, when scientists from the Weizmann Institute of Science in Rehovot, Israel published a study in which they were trying to figure out how bacteria can tell the difference between phosphate and arsenate and "know" to prefer the phosphate. They used phosphate-collecting proteins from four different species of bacteria in their research, including the one that had been at the center of the arsenic life controversy. And along the way, they discovered a fun twist to that story.
Read the rest
Illustration from a peer-reviewed research paper provides poignant commentary on the futility of life
I'm not sure even Chris Ware could have done it any better.
In context, this illustration comes from a recently published paleobiology paper examining a cache of animal bones and pottery found in a sinkhole near China's Jiangdong Mountain.
One of the key things the researchers are taking away from this site: The range of the Giant Panda must have once been a lot larger than it is today.
Here's a link to the paper (which is behind a pay wall)
Via Ed Yong
So, the sky looks blue because of the particular gases in our atmosphere reflect and scatter the blue wavelengths of light from the Sun. Fair enough. But that leads directly to a second question that, I'm ashamed to say, I never really thought to ask — why doesn't the light from all the stars in the Universe reflect and scatter off our atmosphere, producing a blue sky, all the time?
This Minute Physics video provides a great explanation, which is grounded in both the timey-wimeyness of astrophysics and the limitations of our own human biology.
The cost of genome sequencing is starting to sink into the affordable range. (In comparison to its previous cost. We're talking "within reach" the same way Design Within Reach uses the phrase.)
Companies are starting to claim that a $1000 personal genome sequence is on the horizon. But what does that mean for you? Should you save up and get one? Can it really tell you anything meaningful at all? Who is going to sift through all the information your genome represents — and how will they do it?
Tonight, starting at 7:00 Eastern, Science Online New York City is hosting a round-table to discuss these issues, especially the problems associated with collecting, making sense of, and protecting a massive new stream of personal data. The live event is sold out, but you can watch whole thing streaming online.
Panelists: Ronald Crystal, the Chairman of the Department of Genetic Medicine at Weill-Cornell Medical College, who has had his genome sequenced and analyzed it himself. Virginia Hughes, a freelance author who has written about her experience with the 23andMe genotyping service. Manish Ponda of Rockefeller University, who has experimented with other -omic type analyses.
Via Lou Woodley
Creature Cast is one of my favorite blogs — a series of charmingly animated videos about surprising, oft-overlooked details in the animal kingdom. Better yet, the videos are often made by students who work with professor Casey Dunn's evolution and diversity laboratory at Brown University.
In this entry, Riley Thompson, from the College of the Atlantic, explains how transparency — the biological kind — really works. Why can we see through some animals and not others?
Tracy King sends us an "animated history of genetics from Nature to celebrate the release of ENCODE. Narrated by Tim Minchin and animated by the team who made Storm. Written by Adam Rutherford (Nature), Andrew Ellard (Red Dwarf, IT Crowd) and Tracy King (TAM London).
Ever since a monk called Mendel started breeding pea plants we've been learning about our genomes. In 1953, Watson, Crick and Franklin described the structure of the molecule that makes up our genomes: the DNA double helix. Then, in 2001, scientists wrote down the entire 3-billion letter code contained in the average human genome. Now they're trying to interpret that code; to work out how it's used to make different types of cells and different people. The ENCODE project, as it's called, is the latest chapter in the story of you.
Justine Larbalestier provides some context for Republican MO senate nominee Todd Akin statement that, "from what I understand from doctors [pregnancy from rape] is really rare. If it’s a legitimate rape, the female body has ways to try to shut that whole thing down."
It turns out that this belief in magic sperm-rejecting vaginas was the kind of thing that was believed in 1785, when Samuel Farr argued in his groundbreaking treatise on law and medicine that:
Samuel Farr, in the first legal-medicine text to be written in English (1785), argued that “without an excitation of lust, or enjoyment in the venereal act, no conception can probably take place.” Whatever a woman might claim to have felt or whatever resistance she might have put up, conception in itself betrayed desire or at least a sufficient measure of acquiescence for her to enjoy the venereal act. This is a very old argument. Soranus had said in second-century Rome that “if some women who were forced to have intercourse conceived . . . the emotion of sexual appetite existed in them too, but was obscured by mental resolve,” and no one before the second half of the eighteenth century or early nineteenth century question the physiological basis of this judgement. The 1756 edition of Burn’s Justice of the Peace, the standard guide for English magistrates, cites authorities back to the Institutes of Justinian to the effect that “a woman can not conceive unless she doth consent.” It does, however, go on to point out that as matter of law, if not of biology, this doctrine is dubious. Another writer argued that pregnancy ought to be taken as proof of acquiescence since the fear, terror, and aversion that accompany a true rape would prevent an orgasm from occurring and thus make conception unlikely.
(Quote from Thomas Laqueur’s Making Sex).
Justine notes that Farr's work was written in the same century in which Mary Toft was widely believed to have given birth to rabbits.
So yeah, that the kind of "science" that Todd Akin will bring to the Senate.
Given the trend lately to look backwards, historically, in search of the ideal human diet, I found this article by Rob Dunn really interesting. Dunn discusses some new research that gives us a better idea of what our closest relatives—chimpanzees and bonobos—are eating out in the wild.
Some of the takeaways fit neatly into the current human food zeitgeist—chimpanzees eat a diverse and varied diet, only consume small amounts of meat, and (for obvious reasons) focus on what happens to be in season and available. But some of the information is less apparently applicable to us. For instance, chimpanzees fracking love figs. In fact, different species of figs make up nearly half of all the food the chimpanzees in the study were eating. Figs, people. Can't get enough of 'em.
But the larger point, Dunn writes, is that we can't really apply any of the facts about chimpanzee diets directly to ourselves in a "Just So Story" sort of way. Geography, resource availability, and culture don't work like that. Neither does biology.
You are unlikely to eat like a chimpanzee eats. If you are the average American, you eat more meat and more simple sugar. You eat differently because of choices you make and choices our societies have made (e.g., to produce huge quantities of the foods that most simply satisfy our ancient urges). You also eat differently because the species around you are different, unless you happen to own a greenhouse specializing in tropical African trees.
But even if you were to abandon agricultural food and move into a forest in Tanzania you would still not eat exactly like a chimpanzee. By most reports the food chimpanzees eat tastes bad, at least to humans, (though, one hopes, not to chimpanzees). By some accounting the food chimpanzees eat is also insufficient to keep a human alive and fertile.
Spiders don't have an internal skeleton like we do. Instead, their muscles are anchored to an exoskeleton—a sort of hard, semi-flexible shell that encases a spider's whole body. In order to grow bigger, spiders have to grow new exoskeletons and shed old ones.
Karli Larson found a spider on her window frame in the process of shedding its exoskeleton. Naturally, she filmed it and set the whole thing to music. She says:
The entire molting process took about 30 minutes to fully complete. This is the interesting part, sped up.
The camera is a little shakey, so if that bothers you, well, sorry. But I think this is still way fascinating.
Read more about spiders, their exoskeletons, and the molting process at HowStuffWorks
Thanks, Maggie Ryan Sandford!
IUDs are the weird form of birth control. We don't really know exactly how they work, for instance. And they've been largely unpopular my entire lifetime—really, ever since a couple of poorly designed IUDs set off a mini-panic in the late 1970s and early 1980s. But IUDs are effective birth control. The ones that you can buy today are safe. And, more importantly, they represent birth control that you don't have to think about, and birth control that is really hard to get wrong.
If you've ever done research on the effectiveness of various methods of birth control, you'll notice that the statistics usually come with a little asterisk. That * represents a concept that few of the people who rely on birth control ever think about—perfect use. Let's use condoms as an example. With perfect use, 2 out of 100 women will get pregnant over the course of a year's worth of condom-protected sex. Without perfect use—maybe you don't use a condom every time, maybe you don't put it on right when you both get naked—the number of accidental pregnancies jumps to 18 out of 100. The same basic problem affects birth control pills, as well. Ladies, did you know you're supposed to take those things at the same time of day every day? That's the kind of use error that can make a difference between 1 out of 100 women getting pregnant in a year, and 9 out of 100 getting pregnant.
In contrast, IUDs represent a fit-it-and-forget-it method of birth control. Which is a big part about why they're up there with outright sterilization as the most effective means of birth control available. Bonus: Depending on which kind you use, you can avoid hormonal side effects. This, experts say, is why IUDs are experiencing something of a resurgence in popularity. In an article at Wired, Jennifer Couzin-Frankel writes that 5.5 percent of American women who use birth control use IUDs. That's up from only 1.3 percent in 1995.
Somewhat unbelievably, no one is quite sure how they work, but the theory goes like this: The human uterus has one overriding purpose, which is to protect and sustain a fetus for nine months. If you stick a poker-chip-sized bit of plastic in there, the body reacts the way it does to any foreign object, releasing white blood cells to chase after the invader. Once those white blood cells are set free in the uterus, they start killing foreign cells with efficient zeal. And sperm, it turns out, are very, very foreign. White blood cells scavenge them mercilessly, preventing pregnancy. In copper- containing IUDs, metal ions dissolving from the device add another layer of spermicidal action.
... Most modern IUDs incorporate copper, which has an assortment of benefits, including increased durability and effectiveness. They’re also free of hormones and can be made cheaply, a boon for women in developing countries. But copper IUDs can cause heavy menstrual bleeding and cramping. The Mirena solves that problem by forgoing the metal for a synthetic version of the hormone progesterone. Here again, the mode of action isn’t completely understood, but researchers suspect that the hormone thickens cervical mucus, which makes it nearly impossible for sperm to swim upstream. It may also thin the uterine lining, rendering it inhospitable to an embryo should fertilization occur. The hormone-based IUD has the opposite side effect of the copper ones: It sometimes leaves women with little uterine lining to shed, so they hardly get any period at all.
... Even though many more doctors are comfortable with the IUD, a generation of doctors didn’t get practice inserting it. And if they don’t know how to put one in, they’re less likely to recommend it as an option. Also, the devices are expensive—the ParaGard costs $500, the Mirena $850. “It’s absolute highway robbery that these companies charge so much,” Espey says. “If you went to Home Depot and got the raw materials for a copper IUD, it would cost less than 5 cents.” And the hormones don’t contribute much more to the cost, she adds. In fact, amortized over years of use—10 for the ParaGard and five for the Mirena—an IUD is far cheaper than birth control pills, which can cost $30 or more a month. But the initial outlay is difficult for some women to manage, and it’s not always covered by insurance.
Read more about different kinds of birth control, their effectiveness, and how to use them correctly at Planned Parenthood
Image: X-Ray showing an IUD in place. Photo taken by Wikipedia user Nevit Dilmen, used via CC license.
Many's the time I've rolled around on the ground, grimacing and making animal keening noises and wondering why the hell humans evolved to experience such dramatic pain from toe-stubbing. Here is a plausible-sounding threefold answer from Chris Geiser, director of Marquette College's College of Health Sciences athletic training program. Part one is that we've just got a lot of nerves in our extremities because they're our interface to the world. But more interestingly:
Secondly and related to the first point, there is very little tissue in our toes to absorb this type of impact. Much like hitting our shin, there is no fatty tissue or muscle tissue overlying the bones in the toe to cushion the impact. Every bit of the kinetic energy created in moving our legs forward is absorbed by the skin and bone of the toe, resulting in very high compressive forces on the many nerve endings that reside there. Because the foot is at the end of the longest lever system in the body — the leg — feet tend to be moving much faster than any other part of the body when they come into contact with an unknown object. For these same reasons a pitcher can throw a baseball 90-plus miles per hour and a soccer player can strike the ball at roughly the same speed; the further away from the axis of rotation, in this case our hip, the faster the end of that segment is moving. Add the mass of our entire leg to this equation, and there's a large mass applying force to the toe at a great velocity in a small area not capable of adequately dissipating that impact. OUCH!
"The last part of this explanation comes from an evolutionary perspective. In the not so distant past, infections killed many people. Stubbing a toe can open wounds on the feet, which are constantly in contact with the bacteria-laden environment. It has been suggested that individuals who received lots of sensory information from their toes were less likely to strike them, creating an evolutionary advantage for people blessed with this type of sensory information. So there are many components to this amazingly painful question."
"As a biologist, seeing this fossil represents something of a pilgrimage," says Bryan, "[Visiting this museum is] a journey that all biologists would benefit from making."
Snip from his blog post:
This particular sample was found in the Solnhofen limestone formation in Bavaria and is the basis for the link between the dinosaurs and the feathered birds. Archaeopteryx itself is a feathered theropod, but is though of as the oldest documented bird dating back approximately 150 million years ago.
The fossil was found in 1874 by Jakob Niemeyer who traded it to Johann Dorr for a cow. Johann then sold the fossil to Ernst Haberlein for 2,000 German Marks. This sale was then turned around to the founder of Siemens, Werner von Siemens for 20,000 German Marks for the University of Berlin which has provided this specimen to scientists around the world as the best preserved specimen found with elegant feathers and an exquisitely preserved skull.
From a public perspective, biology in the oceans, like biology on the land, tends to favor the charismatic megafauna. Stop by your local aquarium and you’ll find masses huddled around the seal pool or the shark tank.Read the rest
Last January, at the Science Online conference, I noticed that there was a research group collecting swabs taken from the bellybuttons of scientists, science bloggers, and science journalists. That culture above? It's made from the bellybutton of Anton Zuiker, one of the organizers of that conference.
Beyond personalized petri dishes, what is the point of all this? Turns out, the goal is to learn more about the bacteria that lives on us. Some of the data from analyzing all those bellybutton samples is starting to come back, and it's turning up some interesting facts about the tiny ecological niches on our tummys.
About 18 months ago, researcher in the laboratory of Dr. Dunn, a North Carolina State University professor, came up with an idea to explore the ecology and evolution of daily life and wanted to find a spot on the body that could provide an understanding of the natural skin microbiome. They needed a place that was infrequently disturbed, avoided the scrubbing of daily wash and was common to all humans. There was no better choice than the bellybutton. Dunn and his clan of navel gazers then invited people from two conferences, 60 in total, to swab their bellybuttons and provide him with the samples, which he took back to his lab and cultured. The next several months were spent not only growing the bacteria, but also typing them to identify the species.
The first set of data is in review, but the results suggest that the bellybutton offers far more to our understanding of life and our journey through it. From these 60 people, Dr. Dunn identified close to 1,400 species of bacteria. From these, a number were predictable, such as the ever-prominent Staphylococcus epidermidis and the corynebacteria, both of which give off that "eau de germs" scent when we don't wash frequently. But others, such as those found on volunteer Carl Zimmer, were completely unexpected, such as species that are found only in the ocean or the soil or in faraway lands.
...The navel bacteria were related to where the person has lived over the course of their lifetime. The tiny anatomical vestibule was actually a museum of lifetime experiences.
Read the rest of this story by microbiologist Jason Tetro at Huffington Post.
Learn more about the Bellybutton Biodiversity Project
Slate has a nice explainer covering heat wave health problems. The central question: If my body temperature is 98.6 degrees Fahrenheit, why am I uncomfortable when it's 98.6 degrees Fahrenheit outdoors?
The answer is both basic and interesting. Sure, 98.6 degrees F is the healthy temperature for a human body, but that's only because we are pretty good at transferring heat away from ourselves. Your metabolism and your muscles generate more heat than that, but you get rid of it using tricks like breathing out hot air and sweating. Basically, your body works like a heat exchanger. It's the same sort of system that keeps your refrigerator cool—take the heat from inside a closed space and dump it into the surrounding environment.
Unfortunately, this system works best when the surrounding environment is cooler than the closed space. Your body is happiest when the air temperature is around 70 degrees F. That's when it's most efficient at getting rid of your excess heat. When the weather gets to warm, it's a lot hard to make the heat exchange. With nowhere else to put the heat, your body temperature starts rising.
Because exercise causes the body to generate so much extra heat, optimal temperatures for intense physical activity are lower than those for daily life. Athletes can raise their core temperatures six degrees just by working out. Add an environment that makes heat dispersal more difficult—not to mention possible dehydration from sweat losses that sometimes exceed six liters (for marathoners) or two liters per hour (team game players)—and performance can take a nosedive.
... For example, researchers in Darwin, Australia, observing a long-distance runner taking a 30-minute jog through the humid air, noted that his body temperature increased from 98.96 degrees to 105.8 degrees. When he’d gone on a similar jaunt under cooler conditions, his temperature had risen by just two degrees. Such a spike spells trouble for maintaining an optimal heart rate: The man’s soared to 200 beats per minute during the last 15 minutes of his run, where, previously, it was a more sustainable 154 beats per minute.
Read the rest of Slate's Explainer on body temperature.
Sea urchin egg undergoing mitosis with fluorescent-tagged/stained DNA (blue), microtubules (green).
Sea urchin egg undergoing mitosis with fluorescent-tagged/stained DNA (blue), microtubules (green).
Cells divide. One single piece of life tugs itself apart and splits in two.Read the rest
Today, we're the only living member of the genus Homo and the only living member of the subtribe Hominina. Along with chimpanzees and bonobos, we're all that remains of the tribe Hominini.
But the fossil record tells us that wasn't always the case. There were, for instance, at least eight other species of Homo running around this planet at one time. So what happened to them? What makes us so special that we're still here? And isn't it just a little weird and meta to be fretting about this? I mean, do lions and tigers spend a lot of time pondering the fate of the Smilodon?
Today, starting at 12:00 Eastern, you can watch as a panel of scientists tackle these and other questions. "Why We Prevailed" is part of the World Science Festival and features anthropologist Alison Brooks, genome biologist Ed Green, paleoanthropologist Chris Stringer (one of the key researchers behind the "Out of Africa" theory), and renowned evolutionary biologist Edward O. Wilson.
You can also join in a live conversation about the panel, which I'll be hosting. Just post to Twitter with hashtag #prevail, or join us at UStream.