The domestic history of goats
How and where were goats domesticated? 10,000-year-old DNA might be able to tell us.
A genomic study of ancient goat remains from the Zagros Mountains in Turkey and northern Iraq, published in PNAS, suggests that ancient goatherds were keeping female sheep and removing males from the herd.
The genetics showed that these goats were still very close to wild bezoar ibex, which suggests that the goatherds continued to hunt wild goats while they were domesticating others. This potentially helped avoid a genetic bottleneck due to inbreeding.
“Our genetic results point to the Zagros region as being a major source of ancestry of domestic goats and that herded, morphologically wild goats were genetically on the path to domestication by about 10,200 years ago,” says Kevin G Daly, of Trinity College Dublin, Ireland, who led the study.
Researchers have found that young clownfish living close to shore are dying more quickly than those that live far away, because there is too much light pollution.
“As with many other reef fish, clownfish feed, reproduce, defend their territories and interact with other fish during the day and reset whilst sleeping at night,” says the study’s lead author Jules Schligler, of the École Pratique des Hautes Études PSL Université Paris (EPHE) and the Centre of Island Research and Environmental Observatory (CRIOBE), both in France.
“However, 36% of the clownfish exposed to light pollution were more likely to die than fish under natural light cycles.
“Like humans, fish need a period of inactivity, which is crucial for their well-being.”
The team hopes this will raise awareness about the impacts of light pollution on marine ecosystems.
Their paper appears in Proceedings of the Royal Society B.
Nintendo Wii therapy for balance?
In a paper published in Developmental Medicine and Child Neurology, researchers have found that some video games might help children with cerebral palsy improve their balance, as a part of physical therapy.
“Virtual reality-based rehabilitation using Nintendo® Wii is considered a multi-sensory and active therapy that encourages the child’s participation, increasing motivation and adherence to therapy due to its playful nature,” explains author Esteban Obrero-Gaitán of the University of Jaén, in Andalusia, Spain.
“In addition, it is a low-cost tool that can be used at home for therapeutic purposes, a fact that is of great relevance during the COVID-19 pandemic.”
A giant blinking star spotted near the Milky Way
An international team of astronomers has found a stellar oddball around 25,000 light-years away, near the centre of our galaxy. The team watched as the star, VVV-WIT-08, decreased in brightness by a factor of 30 and nearly disappeared from the sky, before reappearing.
Their paper, published in Monthly Notices of the Royal Astronomical Society, explains that the star might be a new class of ‘blinking giant’ binary star system, where one giant star is eclipsed by a companion – perhaps another star or a planet – every few decades.
“It’s amazing that we just observed a dark, large and elongated object pass between us and the distant star and we can only speculate what its origin is,” says paper co-author Sergey Koposov from the University of Edinburgh.
Astronomers know of only a couple of other star systems that undergo this process, including the giant star Epsilon Aurigae, which is partly covered by a huge disc of dust every 27 years.
Ancient amphibians grew spines for swimming
The now-extinct amphibians varied in size from 0.5–6 metres long, and lived from the Carboniferous Period to the Cretaceous.
Aja Mia Carter of the University of Pennsylvania, US, and colleagues found that the lower portion of the vertebrae – which determines flexibility – varied with habitat: the creatures that lived in water had stiffer spines. Based on these bone structures, they may have kept going back into the water over many generations, and the spine became more rigid each time. This contrasts with other hypotheses that suggest the stiff spines helped with movement on land.