What makes this centipede particularly interesting (besides that great handlebar moustache it's sporting) is the long, fuchsia appendages on its rear end, each one topped with a feathery, yellow bit, like a flag on a pole. According to Naskrecki, nobody knows what those appendages are for. They seem to have evolved from the animal's rear-most legs, but their function is a total mystery.
It could just be cultural connections that make us identify one song as happy and another as sad. But, explains Joe Hanson, there's evidence that our emotional connections to music are more universal than that.
In this video about evolution, music, and smooshy feelings, Hanson describes a study that asked participants to create short lines of music that matched specific emotions. The results were surprisingly similar, whether the participants were Americans, or people from an isolated village in Cambodia.
My dad calls the first few months of a baby's life "the necessary larval stage". I've heard other people refer to it as "the fourth trimester". Basically, newborn human babies are pretty useless, as far as baby animals go. This is especially true in comparison to baby apes, who come out of the womb at a much higher level of development. Scientific American has an excerpt from an upcoming book by Chip Walter that talks about this fact and its connection to two key moments in human evolution — the development of bigger brains (and thus, bigger heads) and walking upright (which has the side effect of creating a narrower birth canal). — Maggie
The populations at lowest risk for developing gestational diabetes — namely, ladies of European decent — come from cultures that eat (and have eaten, for thousands of years) dairy and wheat-heavy diets that would, normally, increase your risk. Meanwhile, writes Carl Zimmer at The Loom, Bangladeshi women, who have one of the highest risks for gestational diabetes, come from a culture that traditionally ate a low-carb, low-sugar diet. What's going on here? The answer might lie in evolution. It's a particularly interesting read given the ongoing pop-culture debate about whether 10,000 years is enough time for humans to adapt to eating certain foods. This data on pregnant ladies would suggest the answer is, at least in some respects, yes. — Maggie
Writer Darren Naish, who blogs at Tretrapod Zoology, took this photo of a Larus gull attempting to chow down on an awkwardly shaped starfish. (And, really, are there any other kind of starfish? Especially when you're trying to fit them in your mouth whole?)
First: When shown images like the one above and asked to choose which men they found more attractive, women cared significantly more about body shape than penis size. (Also, it's worth noting that the image above is meant to show you an average, actual human guy in the middle and the extremes of body shape and penis size that were shown to the women on either side of him. In reality, the women were shown a full spectrum of images mixing different body types and penis sizes).
Second: The hypothesis (that human women sexually selected human males to have the larger-than-other-primates junk they are blessed with today) comes with some big questions, including the obvious — flaccid penis size does not correlate well to erect penis size.
In Tulsa, Oklahoma, over the last 30 years, the number of cliff swallows killed by moving vehicles has drastically decreased. That change can't be accounted for by alterations in traffic patterns or swallow populations, say scientists. Instead, they think it's tied to the fact that the birds' wingspan is also decreasing. This adaptation — whether selected for by vehicular birdicide and/or other factors — helps swallows be more nimble in the air at high speeds, making it easier for them to avoid oncoming traffic. (EDIT: Sorry guys, I made an error here. Some of the researchers were from Tulsa, but study actually happened in Nebraska. Evolution takes place throughout the plains states.) — Maggie
By studying the way it has mutated and changed over time, scientists can trace human mitochondrial DNA — the DNA that is passed from mother to daughter — back to a single woman. Basically, everybody alive is descended from her. But that's not the same thing as saying that Mitochondrial Eve was once the only woman alive. In a very nice piece — with helpful illustrations — the Christian (but evolution-accepting) scientists at BioLogos explain what Mitochondrial Eve really means and why she can't be used as an argument for creationism. Whether or not you've ever found yourself arguing this point with a family member or friend, the piece is really useful for deepening your understanding of a pop-science concept that's often thrown around without a clear explanation behind it. — Maggie