Despite slang terms that imply otherwise, the human penis contains no bones. The same cannot be said for many of our closest evolutionary relatives: Chimpanzees and bonobos both have penis bones (a macaque one is pictured, left), also known as bacula.
To find out why some primates have the feature whereas others don’t, researchers traced the bone’s evolutionary history through time. The baculum first evolved between 145 million and 95 million years ago, as reported in the Proceedings of the Royal Society B. That means it was present in the most recent common ancestor of all primates and carnivores. Why some descendants, like humans, lost their bacula appears to be due to differences in mating practices: In primates, the presence of a penis[ ... ]
Before I begin telling you about this fascinating new glue (adhesive), there's a thing or two you need to know about the animal that inspired it all, the gecko. Geckos are small lizards that have the ability to run up walls and scurry across ceilings with the help of tiny rows of hairs on their feet known as setae. Setae generate a multitude of weak attractions (called Van der Waals forces) between molecules on the two surfaces that add up to a secure foothold. Unlike glue or tape, a gecko’s sticky feet attach and detach effortlessly, which made it a perfect case study for engineers to model.
To create their artificial gecko adhesive, a Stanford team of scientists started by making silicone micro-wedges, which imitated gecko hair. They asse [ ... ]
This lady beetle (Coccinellidae) is protecting its enemy. The cocoon between its legs holds a parasitoid wasp larva (Dinocampus coccinellae), which fed on the beetle’s insides before bursting from its belly. Researchers have discovered what makes the beetles act as babysitters: They are infected with a brain-controlling virus. When the larva emerges and spins its cocoon, the virus makes the beetle freeze in place, protecting the baby wasp from predators.
Bdellovibrio bacteriovorus is a bacterium that attacks other bacteria. It can charge its prey at speeds of up to 100 micrometers per second, comparable to a human running 600 kilometers per hour. It then bores into its hapless victim by spinning at 100 revolutions per second. Most bacteria aren't quite that fast, but they can move by whipping flagella or by spiraling through their environment.
While it may sound counter-intuitive, new research suggests that selectively plucking hairs in very close proximity can stimulate some startlingly dense regrowth. The team behind the study, led by researchers at the University of Southern California, demonstrated that by carefully extracting 200 hairs, one-by-one, from the back of a mouse in a specific configuration and density, they could trigger the growth of around 1,200 new hairs in the area - a five-fold increase. The biological mechanism is shown below:
While it's very early days, the researchers say their findings, which were reported in the journal Cell, could pave the way for new treatments for balding, or alopecia. [ ... ]
A new study has found that most adults, everywhere in the world, are playing host to face mites. They live in our hair follicles, eat the oils we secrete, mate with each other near the surface of our skin, and sometimes venture out at night.
A bacterium previously unknown to science was found in two spacecraft clean rooms, one in Florida and the other in Guiana. Space agencies use these rooms to prepare spacecraft for launch and are considered two of the most sterile places on Earth.
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