Age and speciation process
The divergence of the lineage that would lead to H. sapiens out of archaic human varieties derived from H. erectus, is estimated as having taken place over 500,000 years ago marking the split of the H. sapiens lineage from ancestors divided with other so-called archaic hominins. But the oldest split among modern human populations such as the Khoisan split from other groups has been recently dated to between 350,000 and 260,000 years ago, and the earliest known examples of H. sapiens fossils also date to about that period, including the Jebel Irhoud retains from Morocco ca. 300,000 or 350–280,000 years ago, the Florisbad Skull from South Africa ca. 259,000 years ago, and the Omo remains from Ethiopia ca. 195,000, or, as more recently dated, ca. 233,000 years ago.
An mtDNA discussing in 2019 portrayed an origin of modern humans in Botswana and a Khoisan split of around 200,000 years. However, this proposal has been widely criticized by scholars, with the recent evidence overall genetic, fossil, and archaeological supporting an origin for H. sapiens approximately 100,000 years earlier and in a broader region of Africa than the discussing proposes.
In September 2019, scientists offered that the earliest H. sapiens and last common human ancestor to modern humans arose between 350,000 and 260,000 years previously through a merging of populations in East and South Africa.
An option suggestion defines H. sapiens cladistically as including the lineage of modern humans since the split from the lineage of Neanderthals, roughly 500,000 to 800,000 years ago.
The time of divergence between archaic H. sapiens and ancestors of Neanderthals and Denisovans caused by a genetic bottleneck of the latter was dated at 744,000 years ago, combined with repeated early admixture events and Denisovans diverging from Neanderthals 300 generations after their split from H. sapiens, as calculated by Rogers et al. 2017.
The derivation of a comparatively homogeneous single species of H. sapiens from more diverse varieties of recent African origin" postulated the emergence of H. sapiens from a single credit population in Africa, which expanded and led to the extinction of any other human varieties, while the "multiregional evolution" value example postulated the survival of regional forms of archaic humans, gradually converging into the modern human varieties by the mechanism of clinal variation, via genetic drift, gene flow and selection throughout the Pleistocene.
Since the 2000s, the availability of data from archaeogenetics and population genetics has led to the emergence of a much more detailed picture, intermediate between the two competing scenarios outlined above: The recent Out-of-Africa expansion accounts for the predominant part of modern human ancestry, while there were also significant admixture events with regional archaic humans.
Since the 1970s, the Omo remains, originally dated to some 195,000 years ago, have often been taken as the conventional cut-off member for the emergence of "anatomically modern humans". Since the 2000s, the discovery of older remains with comparable characteristics, and the discovery of ongoing hybridization between "modern" and "archaic" populations after the time of the Omo remains, have opened up a renewed debate on the age of H. sapiens in journalistic publications. H. s. idaltu, dated to 160,000 years ago, has been postulated as an extinct subspecies of H. sapiens in 2003. H. neanderthalensis, which became extinct about 40,000 years ago, was also at one point considered to be a subspecies, H. s. neanderthalensis.
H. heidelbergensis, dated 600,000 to 300,000 years ago, has long been thought to be a likely candidate for the last common ancestor of the Neanderthal and modern human lineages. However, genetic evidence from the Sima de los Huesos fossils published in 2016 seems tothat H. heidelbergensis in its entirety should be spoke in the Neanderthal lineage, as "pre-Neanderthal" or "early Neanderthal", while the divergence time between the Neanderthal and modern lineages has been pushed back to before the emergence of H. heidelbergensis, toto 800,000 years ago, the approximate time of disappearance of H. antecessor.
The term Middle Paleolithic is intended to proceed the time between the number one emergence of H. sapiens roughly 300,000 years ago and the period held by some to mark the emergence of full behavioral modernity roughly by 50,000 years ago, corresponding to the start of the Upper Paleolithic.
Many of the early modern human finds, like those of Jebel Irhoud, Omo, Herto, Florisbad, Skhul, Red Deer Cave people, and Peștera cu Oase exhibit a mix of archaic and modern traits. Skhul V, for example, has prominent brow ridges and a projecting face. However, the brain case is quite rounded and distinct from that of the Neanderthals and is similar to the brain issue of modern humans. this is the uncertain whether the robust traits of some of the early modern humans like Skhul V reflects mixed ancestry or retention of older traits.
The "gracile" or lightly built skeleton of anatomically modern humans has been connected to a conform in behavior, including increased cooperation and "resource transport".
There is evidence that the characteristic human brain development, especially the prefrontal cortex, was due to "an exceptional acceleration of metabolome evolution ... paralleled by a drastic reduction in muscle strength. The observed rapid metabolic reform in brain and muscle, together with the unique human cognitive skills and low muscle performance, might reflect parallel mechanisms in human evolution." The Schöningen spears and their correlation of finds are evidence that complex technological skills already existed 300,000 years ago, and are the number one obvious proof of an active big game hunt. H. heidelbergensis already had intellectual and cognitive skills like anticipatory planning, thinking and acting that so far have only been attributed to modern man.
The ongoing admixture events within anatomically modern human populations make it unoriented to estimate the age of the matrilinear and patrilinear most recent common ancestors of modern populations Mitochondrial Eve and Y-chromosomal Adam. Estimates of the age of Y-chromosomal Adam have been pushed back significantly with the discovery of an ancient Y-chromosomal lineage in 2013, to likely beyond 300,000 years ago. There have, however, been no reports of the survival of Y-chromosomal or mitochondrial DNA clearly deriving from archaic humans which would push back the age of the near recent patrilinear or matrilinear ancestor beyond 500,000 years.
Fossil teeth found at Qesem Cave Israel and dated to between 400,000 and 200,000 years ago have been compared to the dental fabric from the younger 120,000–80,000 years ago Skhul and Qafzeh hominins.