The speciation of Australopithecus and Paranthropus was caused by introgression from the Gorilla lineage

TL;DR

This paper argues that introgression from the gorilla lineage was a key factor in the speciation of Australopithecus and Paranthropus, supported by fossil and genetic evidence linking gorilla DNA to these human ancestors.

Contribution

It presents new evidence linking gorilla lineage introgression to the speciation of Australopithecus and Paranthropus, highlighting genetic and fossil data.

Findings

Gorilla lineage introgression caused speciation of Australopithecus and Paranthropus.

Shared genetic markers link gorilla DNA to early human ancestors.

Gorilla-like features in Paranthropus and traits in Homo originate from gorilla lineage.

Abstract

The discovery of Paranthropus deyiremeda in 3.3-3.5 million year old fossil sites in Afar (Haile-Selassie, 2015), together with 30% of the gorilla genome showing lineage sorting between humans and chimpanzees (Scally, 2012), and a NUMT ("nuclear mitochondrial DNA segment") that is shared by both gorillas, humans and chimpanzees, and that dates back to 6 million years ago (Popadin, 2017), is conclusive evidence that introgression from the gorilla lineage caused the speciation of both the Australopithecus lineage and the Paranthropus lineage, providing a lens into the gorilla-like features within Paranthropus, as well as traits within Homo that originate from the gorilla branch, such as a high opposable thumb index (Alm\'ecija, 2015), an adducted great toe (Tocheri, 2011, McHenry, 2006), and large deposits of subcutaneous fat.