According to the new UCL studies, Neanderthals and modern people differed at least 800,000 years ago, much earlier than most DNA estimates.
A study published in Science Advances analyzed dental evolutionary variables in different types of hominin, focusing on early neanderthals. This shows that the teeth of the Neanderthal ancestral hominines from Sima de los Huesa departed from the line of modern man before.
Sima de los Huesos is a cave located in Atapuerca Mountains, Spain, where archaeologists have recovered almost 30 fossils. Previous studies have indicated that the site was about 430,000 years ago (middle pleistocene), making it one of the oldest and largest human remains found so far.
The excavation site where neanderthal teeth were discovered. (Mario modesto / Public Domain )
Dr Aida Gomez-Robles (UCL Anthropology) said: "Any difference between Neanderthals and modern people under 800,000 years would have been unexpected rapid dental development in early Neanderthals from Sima de los Huesos. "
" There are various factors that can explain these results, including a strong choice to change the teeth of these hominins or their isolation from other continental neanderthals. But the simplest explanation is that the differences between Neanderthals and modern people were older than 800,000 years, so the evolutionary indicators of the early Neanderthals of Sima de los Huesa would be roughly similar to those found in other species.
Contemporary Human Ranges Neanderthal Teeth
Modern people have a common ancestor with neanderthals, extinct species that were our closest prehistoric relatives. However, detailed information on when and how they differed is a matter of intense discussion in the anthropological community.
The old DNA analysis in general showed that the two lines differed between 300,000 and 500,000 years ago, which severely affected the interpretation of the hominine fossil record. However, this difference time is incompatible with the anatomical and genetic similarities of the Neanderthals observed in the Sima de los Huesa hominins. Sima's fossils are considered the real ancestors of the Neanderthals, based on anatomical properties and DNA analysis
Neanderthal dental fossil found in the cave of Sima de los Hues. [UtaUtaNapishtim/ CC BY-SA 4.0 )
Dr. Gomez-Robles said: "Sima de los Huesos hominins have very small rear teeth (premolars and molars) that have many similarities to the classic Neanderthals. It is likely that the small and neanderthal teeth of these hominins have evolved from larger and more primitive teeth located in the last common neanderthal ancestor and modern humans. "
The shape of the teeth evolved very similarly to all types of hominin, including the highly expanded and greatly reduced teeth. This new study looked at the time that Neanderthals and modern people had to differentiate from the evolutionary pace of early Neanderthals from Sima de los Huesa
On the upper side is the upper and lower postanal part of one representative SH individual (A. Muela / ) Fair Use )
The study used quantitative data to measure the shape of the tooth shape for hominins, taking into account different different times between neanderthals and modern people and accounting for uncertainty about different types of teeth.
Sima's human teeth are very different from the ones we would expect to find in their last common ancestral species with modern people, which shows that they have evolved for a long time to create such strict differences.
The study has a significant impact on the identification of the last common ancestral species homo sapiens with the Neanderthals, as this allows to reject all groups that after 800,000 postpartum years.
Top: Neanderthal verses human skull. Source: Bruder / Adobe. In the article Neanderthals and modern people less than 800,000 years ago, different dental studies were originally published in Science Daily.
Source: University College London. " Neanderthals and modern people less than 800,000 years ago, dental research shows ." ScienceDaily. ScienceDaily 2019. May 15