Homo antecessor: characteristics of this extinct species

A review of the characteristics of Homo antecessor, an archaic human species.

Atapuerca is a Spanish locality that has become famous for having been the scene of one of the greatest discoveries in the history of paleoanthropology. In 1994, the remains of the oldest hominid in Europe were found: Homo antecessor. Homo antecessor.

This species is one of the earliest of the genus Homo, but it has some characteristics that can be related to later species, such as Homo heidelbergensis and Homo sapiens sapiens.

Below we will discover a little more about its history, its morphology, the main findings that have been made of the Homo antecessor and the debate on whether it is really an independent species or if it is within other hominids.

What was the Homo antecessor?

The Homo antecessor is an extinct species of hominid considered to be the oldest representative of the genus Homo in Europe and probably an ancestor of Homo heidelbergensis and Homo neanderthalensis. and probably an ancestor of the line of Homo heidelbergensis and Homo neanderthalensis. Based on the remains found so far, it is considered that it must have lived about 900,000 years ago, in the Calabrian age of the Middle Pleistocene.

This hominid has become very well known due to its great importance in the field of paleoanthropology, especially the remains found in Atapuerca. It is near this town in Burgos, at the Gran Dolina site, that, since 1994, remains of the Homo antecessorwhich have allowed a better understanding of the evolutionary history of the Homo genus in Europe.

Morphology

It is believed that the Homo antecessor adults were tall and strong hominids, with a face with archaic features and a brain smaller than that of Homo sapiens. Homo sapiens today. Based on the findings, mainly those of Atapuerca, this hominid had very primitive features in its dental apparatus, a trait which led the scientific community to relate them to African hominids of the Lower Pleistocene. Their height must have been between 160 and 185 centimeters and they weighed between 60 and 90 kilograms.

But despite their resemblance to hominids from earlier times, the mandible of the Homo antecessor has features reminiscent of certain later hominids of the Middle Pleistocene. One of these species with which some similarity has been found are the remains of Homo heidelbergensis, such as those from the Sima de los Huesos, also in Atapuerca. The bones of Homo antecessor suggest a certain gracility in comparison with the Neanderthals, also later than them.also later than the Neanderthals.

Apparently, the face of Homo antecessor was similar to that of Homo sapiens sapiens. This presented a coronal orientation and slight backward inclination of the infraorbital plate. The lower edge of this plate is horizontal and slightly arched and the superciliary arch is double arched.

The encephalic capacity of these hominids, estimated from a fragment of frontal bone, must have been greater than 1000 cm³. As we have mentioned, this brain was smaller than that of present-day humans, with a capacity of 1200-1850 cm³ in the Homo sapiens modern Homo sapiens. In addition, it has been assumed that the brain of the it has been assumed that the brain of Homo antecessor had fewer cerebral convolutionsindicating that the brain surface was reduced.

Sites

Although the site with remains of Homo antecessor Although the most famous site is Atapuerca, more remains have been found in other parts of the planet, suggesting displacements from other parts of the globe. The following are the main sites, putting their findings in chronological order.

1. Gran Dolina (Atapuerca)

In 1994, thanks to the team of archaeologist Eudald Carbonell and paleoanthropologist Juan Luis Arsuaga, the remains of Homo antecessor were discovered at the Gran Dolina fossil site in the Sierra de Atapuerca.

During that year and part of the following year, more than 80 skeletal remains of six individuals were discovered, the best preserved being an upper jaw and a frontal bone of an individual who must have died between 10 and 11 years of age.

Also more than 200 stone tools and 300 animal bones were also found.. Among these lithic tools, a knife carved in stone was found along with ancient hominid remains. The dating of these remains is at least 900,000 years old.

Another important finding from the Gran Dolina site is a female jawbone of Homo antecessor, aged between 15 and 16 years and showing very clear similarities with those of Peking Man, remains of Homo erectus. This suggests an Asian origin of Homo antecessor.

2. Ceprano Man

Almost simultaneously to what was discovered in Atapuerca, in Ceprano, Italy, the upper part of the skull of an individual belonging to the genus Homo with primitive characters was found in 1994.The skull was dated to between 800,000 and 900,000 years ago.

Although in 2003 a new name was proposed for these remains and they were considered a new hominid species, Homo cepranensis, the phylogenetic, chronological, archaeological and geographical characteristics of these bones have led them to be considered remains of Homo antecessor.

The fact that they are remains of Homo antecessor or a new hominid would be easily solved by direct comparison of both sets of fossils. The problem is that this is not possible since the bones found in each set correspond to different anatomical parts or to individuals of different ages.

Likewise, both the Atapuerca and Ceprano bones have in common intermediate traits between the primitive Homo populations of Africa and the more recent Homo heidelbergensis populations. Homo heidelbergensisin Europe.

Given that the name Homo antecessor was proposed before that of Homo cepranensis, in case both bone assemblages are part of the same species, the term Homo antecessor would have nomenclatural priority.

3. Norfolk remains

In 2011 the discovery of several tools was reported near Happisburgh in Norfolk, England. These tools must have been used by Homo antecessor and date back some 780,000 years.

Earlier remains have been found at Happisburgh Beach, as well as numerous footprints left by at least five individuals, one adult and several juveniles, on the muddy sediments of an estuary. footprints left by at least five individuals, one adult and several juveniles, on the muddy sediments of an estuary.

4. Homo sp. from Sima del Elefante (Atapuerca)

In 2008, new skeletal remains were discovered, initially attributed to the Homo antecessor. The remains had been found in 2007 in the Sima del Elefante, a site located only 200 meters from the Gran Dolina site in Atapuerca.

This finding consisted of part of a mandible of an individual about 20 years old and 32 Olduvayense-type silica tools, with a dating of 1.5 years old.The find was dated to 1.2 million years ago, considerably pushing back the presence of hominids in Europe.

The detailed study of the mandible was quite striking, given that a dentition and symphysis were found in it that bring it closer to the oldest hominids from Africa and Dmanisi, Georgia.

However, in this case there are some derived characters in the internal part of the symphysis that have led to identify these remains as Homo spi.e, undoubtedly hominid remains but it is not known exactly to which species they belong..

Although for the moment they are considered as possibly belonging to Homo antecessorAlthough it has not been ruled out the idea that it is a new species of hominid discovered, although it is still to be defined.

Debate

As has happened throughout the history of paleoanthropology, every time a new type of hominid is discovered, or believed to have been discovered, there is debate, and the case of the Homo antecessor was to be no exception. The controversy is especially related to its taxonomic classification and kinship relationships with other species of the genus Homo. with the rest of the species of the genus Homo.

Since no complete adult skull has been found and most of the skeletal remains found to date represent juvenile stages, there are those who consider that it is difficult to ensure that Homo antecessor is a separate species. It has not been possible to compare Homo antecessor remains with other hominids in a completely reliable way, given the absence of complete skeletons of this hominid.

In addition, the line of thought critical of these findings holds that what has been termed Homo antecessor discovered in Europe could actually belong to Homo heidelbergensiswhich inhabited the continent between 600,000 and 250,000 years ago, in the Pleistocene.

Likewise, its discoverers, together with the support of other experts, consider that the remains that have been called Homo antecessor to date are clearly a different hominid species.

The most widely accepted hypothesis is that this is an evolutionary link, a link between the Homo ergasterbefore it, and Homo heidelbergensis. Homo heidelbergensisthe more modern Homo heidelbergensis. In turn, antecessor would be an ancestor of Homo neanderthalensisprobably being the last common ancestor between humans and Neanderthals.