Nasa scientists have discovered that Milky Way settled gradually into its present state only around the time the Sun and earth were forming. Disc galaxies like our own Milky Way were believed to have been formed billions of years ago, however, now scientists have found they settled into the present state as the Sun and solar system were being formed.
“Astronomers thought disk galaxies in the nearby universe had settled into their present form by about 8 billion years ago, with little additional development since,” Susan Kassin, an astronomer at Goddard Space Flight Centre in Greenbelt.
“The trend we’ve observed instead shows the opposite, that galaxies were steadily changing over this time period,” Kassin said in a statement.
Nasa has studied hundreds of galaxies and found that they have continued to evolve contrary to the earlier belief that they reached their current state billions of years before the planets.
***
Learning to cook led to evolution of human brain
London: Learning to cook may have helped the human brain to grow, leading to the development of tools, culture and civilisation, scientists claim.
Scientists led by Suzana Herculano-Houzel, from the Federal University of Rio de Janeiro found the advent of cooking would have provided a much more efficient way of delivering calories to neurons, allowing the brain to expand. Without the invention of cooking humans would have to spend nine hours or more every day eating raw food only to support the 86bn neurons in their brains. Fewer hours spent foraging for food would also have freed up more time for social interaction and creative tasks. This probably contributed further to the evolution of a and complex brain.
The scientists calculated the metabolic needs of both present-day great apes and a range of different early human species. Large apes with energy-hungry bodies, such as gorillas, are already at the limit of achievable brain size with a raw-food diet, the research showed. — PTI