Scientists make the first confirmed sighting of a ginkgo-toothed beaked whale off the coast of Mexico. Plus, the oldest RNA molecules to date and how an obesity drug quietens ‘food noise’.
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A female ginkgo-toothed beaked whale — sporting shark bite scars on her flanks — swims with her calf. (Photo by C. Hayslip from E. Elizabeth Henderson, et al/Marine Mammal Science (CC BY-NC-ND 4.0))
Researchers tracked a mysterious whale call off the coast of Mexico to spot, for the first time, living ginkgo-toothed beaked whales (Mesoplodon ginkgodens) at sea. Researchers used a modified crossbow to grab a tiny skin sample from one of the whales and confirm its nature. The 24 species of beaked whales are rarely seen because they live offshore in deep water and rarely surface, so most of what’s known about them comes from their underwater echolocations and the remains of dead animals. “I can’t even describe the feeling because it was something that we had worked towards for so long,” says bioacoustic scientist and study co-author Elizabeth Henderson. “Everybody on the boat was cheering because we had it, we finally had it.”
The Guardian | 6 min read
Reference: Marine Mammal Science paper
Researchers have found the oldest RNA molecules to date in mummified woolly mammoth tissue. RNA is a fragile molecule, which makes intact ancient samples few and far between. But such samples are sought after because analysing ancient RNA could shed light on the gene activity of extinct animals. Scientists used enzymes to convert RNA in the mammoth tissue to DNA, and then reverse-engineered the original RNA sequences. This technique recovered fragments of RNA from three samples, dated to between 39,000 and 52,000 years old.
Science | 5 min read
Reference: Cell paper
The obesity drug tirzepatide, sold as Mounjaro or Zepbound, can suppress patterns of brain activity associated with food cravings, a study suggests. Researchers measured the changing electrical signals in the brain of a severely obese person who had suffered from persistent ‘food noise’ — intrusive, compulsive thoughts about eating — as they began taking the medication. The study is one of the first to directly measure how blockbuster obesity drugs that mimic the hormone GLP-1, affect brain activity in people, and to hint at how they can curb the urge to eat.
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