New, high-res 3D images of human embryos show a variety of muscles that were “present in our ancestors but normally absent from the adult human.” For example, there are hand muscles that temporarily appear in human embryos but usually disappear before birth. According to the researchers, our human ancestors lost those “muscles from the back of the hand about 250 million years ago as mammals and reptiles split on the evolutionary tree.” From Science News:
These appearing and disappearing, or atavistic, muscles are remnants of evolution, says biologist Rui Diogo of Howard University in Washington, D.C. Such atavistic muscles are built as a base from which to start paring down to the final set of muscles that people are born with, he says. “Losing and specializing, that’s what happens in human evolution.”
Other animals have kept some of those muscles. Adult chimpanzees and human embryos have epitrochleoanconeus muscles in their forearms, but most adult humans don’t. Human’s mammalian ancestors also lost dorsometacarpales muscles from the back of the hand about 250 million years ago as mammals and reptiles split on the evolutionary tree. Lizards still have those muscles, and they appear in human embryos, but then are lost or fuse with other muscles during development and aren’t found in most adults.
“Development of human limb muscles based on whole-mount immunostaining and the links between ontogeny and evolution” (Development)
Listen to ‘dinks and donks,’ Marsquakes, and other weird sounds from the Red Planet
The NASA Insight lander on the Martian surface is equipped with an ultrasensitive seismometer to detect and record vibrations, from marsquakes to soft breezes to other unidentified vibrations. Listen below. From Space.com: If we were on Mars with our ears to the ground, our ears wouldn’t be sensitive enough to detect marsquakes. Even the recordings […] READ THE REST
Cormac McCarthy on how to write a scientific (or any kind of) paper
For twenty years, novelist Cormac McCarthy (The Road, No Country for Old Men) has been an unofficial “editor-at-large” for the Sante Fe Institute, where he is a trustee. McCarthy has helped numerous scientists improve the writing in their technical papers about theoretical physics, complex systems, biology, and the like. In the new issue of Nature, […] READ THE REST
This space geek built a DIY radio telescope for $150
David Schneider built his own radio telescope out of roof flashing, an empty paint thinner can, a free software-defined radio app, USB receiver, and a length of coaxial cable. The whole project cost him less than $150 and he’s already used it to detect galactic hydrogen and monitor the motion of our Milky Way galaxy’s […] READ THE REST
This Bloody Bath Mat is the best shower scare since “Psycho”
Cue the “Psycho” violins. If you’re a true Halloween completist who’s wondering how to deck out your bathroom for the holiday, we have your accessory: The Bloody Bath Mat™. When it’s dormant, this devious prank is a nondescript, almost paper-thin (.03 inch thick) mat, white with a matte finish. Placed beside your shower, it’s the […]
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This foldable carry-on bag expands into a full-size suitcase
Everybody’s an expert when it comes to packing before a vacation. It’s great that you squeezed all that stuff into a carry-on. Now, what happens when you find that must-have pair of shoes or holiday gift? Your options are paying to ship the items or getting an extra bag, and neither of those is ideal. […]
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Turn killer quotes by 50 Cent, Kim Kardashian, Donald Trump and more into wall art
Who can forget the moment our president, the man in charge of a nuclear arsenal, coined the word “covfefe”? Sadly, it’s easy to forget given the frequency and amount of head-slapping sayings he’s given us – not to mention the disposable nature of his favorite mode of communication. But not anymore. There’s now a way […]
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