A global cooling around 34 million year ago appears to have shifted primate evolution and with that human evolution during the Eocene epoch.
Fossil find may fill a gap in evolution thinking
Fossils recently found in what is now southern China show that six fossils have led to the discovery of a new primate species that lived in Asia during the greenhouse state that was the Eocene epoch, which according to K. Christopher Beard, senior curator at the University of Kansas Biodiversity Institute and co-author of a paper that was published yesterday in the journal Science.
“This was a wonderful time to be a primate, because primates like things to be hot and muggy,” according to Beard.
These hot an muggy conditions saw primates do quite well in Asia, Africa, Europe and North America. However, when the Oligocene epoch began and brought a global cooling as well drier conditions, many of the primates in these regions when extinct with most primates only surviving in areas of Africa and Asia generally speaking around the tropics and the equator.
John Fleagle, a respected author of a number of books on primate evolution and a primatologist at Stony Brook University told the Christian Science Monitor that the fossil finds “fill a gap” and that they shed light on “a whole aspect of primate evolution that wasn’t clearly documented before.” Fleagle was not involved in the study published yesterday but had plenty to say about the paper.
The six new primate species
Of the six newly discovered species, four of them strepsrrhine primates similar to lemurs, another came from the haplorhine lineage that still exists in Asia and the last of the six is another haplorhine, more specifically a anthropoid which are the ancestors of apes, monkeys and, well, humans.
During the Eocene epoch anthropoids thrived in Asia but upon the arrival of the cold and the Oligocene epoch, they began disappearing rapidly.
While the lemur-like primates did well in southern Asia something quite different occurred during the Oligocene in Africa where the non-anthropoids went extinct and a “radiation occurred. Radiation is used by evolutionists to describe an explosion of new species including monkeys and apes from which we ultimately evolved.
“This is kind of an answer to a paradox that we knew about before,” Beard says. “All of the data that we have from the fossil record of primate evolution indicates that the very earliest anthropoids, the earliest members of this monkey, ape, and human group, actually originated in Asia, not in Africa. But we know by studying later chapters of this story that eventually the plot shifts from Asia to Africa.”
“We never knew when and we never knew why. Now we know when for sure,” he says.
“We now dominate the planet, but we’re here based on a historical contingency that occurred 34 million years ago. Our distant ancestors faced a climatic challenge 34 million years ago and, in Asia, our closest ancestors were not able to meet that challenge. Ultimately the Asian anthropoids went extinct,” says Beard as a warning on climate change. While very few scientists are calling for a global cooling anytime soon, climate change is climate change whether it’s getting colder or warmer and will have evolutionary effects down the line.
