Tuesday , May 18 2021

Fossil record of "The Cradle of Humankind" gives a picture of early climate change – Xinhua



The survey, launched on Thursday by an international group of scientists, including those in Australia, creates a much more definitive understanding of how and when our ancestors evolved and even what the climate was when they did.

It has long been accepted that the origins of mankind are in Africa and that the fossils have recovered from the cradles properly called "Cradle of Humankind" in South Africa that have told us so.

However, to date, scientists have endeavored to create a clear calendar for fossils due to the lack of adequate dating methods available.

Trobe University professor Andy Herries, who researched sites, said that "while the record in South Africa was the first to show Africa as a point of origin for people, the complexity of the caves and the difficulty of meeting them meant that the record was hard to interpret. "

"In this study we show that cave stones in caves can act almost like the volcanic layers in East Africa, forming themselves in different caves at the same time, allowing us to directly relate their sequences and fossils in a regional sequence, he said.

The increase in the World Heritage of the Human Caves has produced nearly 40% of all known ancestors' fossils, including the famous Australopithecus africanus skull, nicknamed Ms. Ples.

According to Robyn Pickering, senior scientist at the University of Cape Town, team meetings provide "a model to explain the age of all fossils across the region," as well as creating an image of our ancestors' climatic conditions.

"Flower stones are the key," said Pickering.

Precious stones are deposits of calcite or other carbonate minerals that form when water enters caves.

"We know that significant stones only grow in caves during wet periods, when there is more rain outside the caves – by dying flower stones, we choose these times of high rainfall," Pickering said.

Using uranium-lead dating techniques developed at the University of Melbourne, the team analyzed 28 layers of stone that are placed between fossil-rich sediments in eight cradles on Cradle – revealing that fossil ages fall into six narrow windows between 3, 2 and now 1.3 million years.

"Therefore, we know that during the interwar period, when the caves were opened, the climate was drier and more akin to what we are experiencing today," she said.

According to experts, this is an astonishing breakthrough that significantly contributes to the self-record of humanity and understanding in the life of the common ancestors from which we have evolved.


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