Scientific news in small doses

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

Mathieu Perreault
The Press

Sperm whale clans

The great Pacific sperm whales are divided into seven linguistic clans, according to German biologists. This is the first time that a symbolic division of a population has been observed in animals. Researchers from the Max-Planck Institute published, at the beginning of September in PNAS, their analysis of 23,429 sets of click sounds, captured in 23 Pacific locations. Sperm whales that never encounter sperm whales from other clans use their “tongue” less, that is, the clicking sounds typical of their clan, than sperm whales that often encounter sperm whales from other clans.

Quiz

What new concern is being raised about internet satellite megaconstellations?

They could hamper planetary defense against asteroids, according to a survey of 34 experts in the field. A quarter of them were extremely concerned that the constellations of thousands of low-orbiting satellites, such as SpaceX’s Starlink, would interfere with observations at dusk — an important time for detecting new asteroids that may be approaching Earth. The survey from the Olin College of Engineering in Massachusetts, published in early September, also points out that the mega-constellations of satellites will complicate the launches of probes, used in particular in the context of a possible mission to hijack or destroy an asteroid. threatening.

The number

3

Three million years. This is the maximum age of the youngest exoplanet ever observed, a feat accomplished by astronomers at Harvard University. Sketched by the ALMA observatory in Chile, this youth belongs to the LkCa 15 solar system, located 518 light years from Earth in the constellation of Taurus. The star LkCa 15 is relatively young and is surrounded by a “protoplanetary disk” where the exoplanet hides, which is 42 times farther from its star than Earth is from the Sun. This exoplanet, whose existence was advanced in 2015 and then rejected, could only be a million years old. The study was published in the Astrophysical Journal Letters.

From legs to brain

Older people who have low muscle mass in their legs have a twice as high risk of cognitive decline three years later, according to a new study from Montreal. The McGill University researchers, who publish their results in JAMA Network Open in early September, observed this cognitive decline (which does not affect memory) in the 20% of guinea pigs with the weakest legs. In the magazine sleepingresearchers at Concordia University noted that among adults with good sleep at baseline, 2% were diagnosed with insomnia three years later — and these insomniacs were 1.7 times more likely to experience trouble of memory.

Maple syrup for psoriasis

A molecule in maple syrup could be used against psoriasis. Quebecol, identified in 2011 at Laval University, seems (in a test tube) to hinder the proliferation and differentiation of skin cells typical of this disease, concludes a research team at the beginning of September in the journal Pharmaceuticals. Quebecol, a polyphenol, could also be used against arthritis. Polyphenols have antioxidant properties.