Human evolution; last of H. erectus on Earth (Introduction)

by David Turell , Wednesday, December 18, 2019, 22:34 (1591 days ago) @ dhw

A very careful timed study on Java:

https://cosmosmagazine.com/palaeontology/the-final-stand-of-homo-erectus?utm_source=Cos...

"The disputed age of the youngest known Homo erectus remains on the Indonesian island of Java has been revised, effectively ruling out any overlap between the archaic human species and anatomically modern humans.

***

"The bones in question – 12 skull caps and two lower leg bones – were discovered in the 1930s by Dutch explorers near the Solo River at Ngandong in Central Java.

***

"Homo erectus has emerged as the most widespread of our ancient relatives. Remains throughout Africa, in Georgia in the Caucasus, in eastern China and on the Indonesian archipelago as far east as Java are all now considered to have come from the same long-surviving species.

"The species emerged as far back as two million years ago, but exactly how long they persisted has been a mystery.

"By the look of the Ngandong remains, they belonged to some of latest surviving members of the species.

***

"To narrow the age estimate even further, the team excavated at sites upstream and downstream of Ngandong, gathering 52 age estimates in total from different terrace layers using a range of different dating techniques.

“It's a much bigger scale, much more comprehensive approach to establishing a chronology for this site than has ever been attempted before,” says Westaway.

"Each of these 52 age estimates had margins of error: some were minimum ages, others maximum. The team used Bayesian modelling to combine these estimates and arrived at a final approximate age for the bone bed of 117,000 to 108,000 years old.

"The finding suggests that Homo erectus lived on Java for more than 1.4 million years.

"The new date rules out any co-habitation on the island with anatomically modern humans, who only arrived in the area after about 75,000 years ago, and the possibility that Homo erectus met its end at the hands of modern humans.

"It doesn’t rule out interactions with other hominins, including Denisovans, says Westaway. Some scientists have even suggested that the changing appearance of Homo erectus over time could be sign of hybridisation rather than the simple march of evolution. (my bold)

"Finding evidence to back up such tantalising theories will, of course, require more work, says Westaway. Drawing a line under the last appearance of the species is a good start.

Comment: Like the Hobbits, isolation seems to have helped them to exist until more recent times. For me it calls into question Gould's punc-inc theory that isolation produces evolution. And think, they lived in the time of H. habilis, Neanderthal, and early H. sapiens. A bush of Homos, just like the bush of life. Evolution follows a bushy pattern.