Science Friday

The cassowary, a large flightless bird native to Australia, New Guinea, and nearby islands, has a reputation for aggression and wickedly clawed feet that can cause serious injury. Indeed, they’ve been known to attack humans dozens of times, and even occasionally kill people.

But they also have a beauty trick: Their glossy black body feathers have a structure for producing shine that’s never before been seen in birds. Where other black birds like crows are shiny because of structures in their feather barbules, the cassowary instead derives its shine from a smooth, wide rachis—the main “stem” of the feather.

University of Texas paleontologist Julia Clarke explains how the cassowary’s color could help shed light on the feathers of extinct birds and dinosaurs—and how paleontologists are investigating the evolution of birds as we see them today.

The novel coronavirus SARS-CoV-2 has primarily been considered a respiratory virus, causing acute problems in the lungs. But doctors around the world have recently been reporting unusual blood clotting in some COVID-19 patients. The exact cause of these blood clots isn’t yet known—there are several interacting biological pathways that all interact to create a blood clot. One theory is that the clotting is related to an overactive immune response, producing inflammation that damages the lining of small blood vessels. Other theories point to the complement system, part of the overall immune response. 

Ira speaks with hematologists Jeffrey Laurence of Weill-Cornell Medicine, and Mary Cushman of the University of Vermont Medical Center about the unusual clotting, how it impacts medical treatment, and what research they’re doing now in order to better understand what’s going on in patients. 

The history of a group of people can be reconstructed through what they’ve left behind, whether that’s artifacts like pottery, written texts, or even pieces of their genome — found in ancient bones or living descendents.

Scientists are now collecting genetic samples to expand the database of ancient East Asian genomes. One group examined 26 ancient genomes that provide clues into how people spread across Asia 10,000 years ago, and their results were published this month in the journal Science.

Biologist Melinda Yang, an author on the study, explains how two particular groups dominated East Asia during the Neolithic Age, and how farming may have influenced their dispersal over the continent.