Friday, November 11, 2016

Lizards help us find out which came first: the baby or the egg?

"Have you ever wondered why we give birth to live young rather than lay eggs? Scientists have pondered this for a long time and answers have come from an unlikely source: some of Australia’s lizards and snakes!"

Writes PhD Candidate  of the  University of Sydney in The Conversation

"In research published this month in the American Naturalist, my colleagues and I at the University of Sydney studied reptile pregnancy to identify the factors necessary for a placenta to evolve.

"Although most reptiles lay eggs, live birth has evolved many times in the group of reptiles that includes lizards and snakes.

"Some of Australia’s most iconic species, have discarded egg-laying and instead hang onto their babies for the duration of pregnancy and give birth to fully developed young.

 Full Article
Original published under a CC-By-SA license.

Sunday, November 06, 2016

Warratyi shows Australia's outback settled by humans 49000 years ago

Clifford Coulthard, an Adnyamathanha elder, was surveying gorges in the area in South Australian when "nature called". He happened across a rock shelter, which has turned out to be one of the most important prehistoric sites in Australia. The site, known as Warratyi, shows that Aboriginal Australian occupied the country 10,000 years earlier than first thought - about 49,000 years ago.

Wikipedia also has a stub article on Warratyi