Because evolution of modern man is a topic covered by gene-environment interactions, these GEITP pages have kept up-to-date on the latest advances in how we Homo sapiens got here, today. The first of our “close relatives” Homo neaderthalensis was first discovered as a fossil in the Neander Valley (Germany) in the 1850s, and the first publication of Neaderthal DNA was from mitochondria (mtDNA) in 1997. Since these GEITP pages have begun in 2008 — there have been additional sublines identified and DNA sequenced: Homo denisova, Homo floresiensis (small hobbitt-sized humans from Flores island in Indonesia), and now Homo luzonensis (from island of Luzon in The Phillippines).
Hominins are members of the human family tree who are more closely related to each other than they are to chimpanzees and bonobos (divergence of 6-7 million years ago). Most extinct hominin species are not our direct ancestors, whereas our close relatives (divergence 600,000-850,000 years ago) had an evolutionary history that took only slightly different paths from ours. Authors [see attached article] identified this new close relative, named Homo luzonensis after Luzon; specimens of H. luzonensis were dated to minimum ages of 50,000 and 67,000 years old — which suggests that this species was alive at the same time as H. sapiens, H. neaderthalensis, H. denisova, and H. floresiensis.
Hominins appear in the fossil record ~6 million to 7 million years ago in southeast Africa, and the earliest hominin fossils found in Eurasia are about 1.8 million years old. Explanations for the earliest hominin dispersals from Africa fall under what is known as the “Out of Africa I paradigm.” Modern humans only come into focus in the “Out of Africa II paradigm,” which refers to the early dispersals of H. sapiens from Africa to Eurasia that first occurred in the past 200,000 to 300,000 years. Homo erectus (discovered in Indonesia on island of Java) is commonly believed to be the only early hominin that was part of the Out of Africa I dispersal ~1.5 to 2 million years ago, spreading across Africa and Eurasia. Meanwhile, other hominin species (2 to 7 million years ago) — e.g. Homo habilis, the australopiths, and more than a dozen others — had smaller brains and anatomy less similar to that of modern humans and died out, while remaining in Africa.
Authors [see attached report] describe specimens from Luzon that display a combination of primitive and derived morphological features that is different from the combination of features found in other species in the genus Homo (including Homo floresiensis and Homo sapiens) and authors believe “warrants their attribution to a new species,” which they name Homo luzonensis. This publication, however, DOES NOT INCLUDE WHOLE-GENOME SEQUENCING and therefore much more will be understood about this subline, and where it fits (in the Greater Realm of Things) when WGS has been completed — which will undoubtedly happen very soon. 🙂
DwN
Nature 11 Apr 2o19; 568: 181-186 & News’N’Views editorial pp 176-178