Scientific news in small doses

A few milligrams of all the scientific news of the week.

pre-colonial horses

American and French researchers have succeeded in reconciling the traditional knowledge of the American Great Plains natives and modern genetics. The Lakota, Comanche, and Pawnee believe that hunting on horseback has always been part of their way of life, even though there were no horses in America before the arrival of Europeans. In Science at the end of March, paleontologists from the universities of Colorado and Toulouse reveal that the horses of these tribes are descended from Spanish horses of the early 16th century^e century. When the Americans arrived in the region 200 to 300 years later, hunting on horseback was therefore well established.

Quiz

What new animal species has been shown to be vulnerable to avian flu?

Seal. More than 330 seals died last June and July, in New England, from the H5N1 avian flu which has hit the world for several years. It is the first marine mammal that is likely to catch bird flu, which has affected ferret farms, bears and many seabirds, a probable source of contamination for seals. More than 6.5 million farmed birds died or had to be culled due to avian flu in Canada in 2022. The study from Tufts University, in suburban Boston, was published in mid-March in the journal Emerging Infectious Disease.

The number

1 month

That’s the lengthening of the annual growth span of trees in Ohio after a century of global warming, according to a study published in mid-March in the journal PLOS One. Climatologists at Ohio State University unearthed detailed observations from a farmer in Wauseon, upstate, who noted the beginning and end of foliage between 1883 and 1912. The fall leaves now occurs a month later on average.

The Mysteries of Mercury

Mercury is the smallest planet in the Solar System, with a size 20 times smaller than that of Earth, but it is also the second in density. American and French researchers think they understand how the planet closest to the Sun was formed, a phenomenon that intrigues astronomers. Based on probe data Messenger, who studied Mercury from 2011 to 2015, they explain that the giant planets (Jupiter, Saturn, Uranus and Neptune) formed much closer to our star, then moved away from it, attracting one another. other. In doing so, they have agglomerated most of the protoplanets close to the Sun. This ballet also led to collisions between protoplanets which crumbled the crust of Mercury, which explains why its core represents 85% of its size, compared to 50% for the Earth. The study was published at the end of March in the journal Icarus.

Taste and asthma

Taste receptors could be put to work in the fight against asthma, according to a new Israeli study. In mid-March, in the Journal of Medicinal Chemistry, immunologists from the Hebrew University of Jerusalem presented a molecule that activates taste receptors located in the respiratory tract. These receptors enlarge the size of the airways.