Smelly flies, phony fossils, and more stories you might have missed this week
Did the asteroid that decimated the dinosaurs also give birds a boost? How do Andean highlanders thrive at altitudes that make most people dizzy? And why are epidemiologists so interested in mosquito poop? Check out the answers below in some of our favorite selections from Science’s daily newsletter, ScienceAdviser.
Female flies ditch sperm if they sniff out a better mate
Female vinegar flies (Drosophila melanogaster) often have many potential suitors and will mate with multiple males in succession. Yet not all of their mates father offspring: Females can selectively fertilize their eggs with the sperm from the male they prefer and eject ejaculate from mates they deem to be of lesser quality. In a bioRxiv preprint published last month, researchers discovered that female flies don’t actually need to see a high-quality male to make this choice: A whiff of his pheromones will do.
Different mutations, same gene. How two populations of humans survive extreme altitudes
The human body is best suited for life at low elevations, where oxygen is plentiful. If you venture above 2500 meters, you may suffer the effects of altitude sickness—symptoms such as nausea, confusion, and swelling of the lungs and brain. But thin air isn’t a problem for the Quechua people of Peru, who have lived high up in the Andes Mountains for more than 10,000 years.
Now, the authors of a study published last week in Science Advances have pinpointed a genetic variant that may have helped this population adapt to life at extraordinary heights. Surprisingly, Tibetans in the Himalayas possess a different mutation in the same gene, suggesting both groups independently evolved similar adaptations to high-altitude living.
Mosquitoes may transmit viruses to other mosquitoes via poop
Female mosquitoes often land on standing water to lay their eggs, quench their thirst, and use the toilet. But those same pools may be home to mosquito larvae still developing into the flying, annoying insects we love to hate. And if those pooping females are carrying West Nile virus, they just might pass the virus on to the younger animals, researchers report in a recent bioRxiv preprint. Knowing more about this “diagonal transmission”—a previously unknown mode of transfer for the virus—could help epidemiologists better predict West Nile’s behavior and spread.
Birds might have boomed long before dinos died
Some 66 million years ago, an asteroid collided with Earth, killing the dinosaurs and bringing the Cretaceous period to an explosive close. Yet the ancestors of all modern birds, from the diminutive hummingbird to the monstrous cassowary, survived and thrived. Paleontologists have long believed the catastrophe eliminated birds’ competition for resources, which allowed them to rapidly diversify into the 10,000 or so species alive today. But a new study, published this week in the Proceedings of the National Academy of Sciences, suggests birds were already a diverse bunch before the asteroid wiped out the dinos.
The remarkable fossil … that wasn’t
In 1931, an employee at a natural history museum discovered an incredible fossil near a small village in Italy: a small lizard remarkably preserved, its former skin creating a dark body shape in the rock. Decades later, a paleontologist came across the find, dubbed Tridentinosaurus antiquus, and instantly recognized how extraordinary it was. Soft tissue preservation like that is extremely rare, and at roughly 280 million years old, it was one of the oldest reptile fossils from the area. Scientists itched to get a more detailed look at the fossil, but they held back for decades, as the only methods available were highly destructive, and it was too special a specimen to destroy.
Or, so they thought. The authors of a study published yesterday in Paleontology employed cutting-edge, minimally destructive technologies to examine the fossil in depth. And that revealed the unfortunate truth: Although there is a genuine reptile fossil in the rock, the supposed soft tissue is just paint.
And finally …
Gas leaking from volcanoes may have turned Earth into a snowball for 56 million years, mushroom genes make petunia plants glow green, and an adorable frog might be the world’s smallest vertebrate.