Homo antecessor

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Homo antecessor
Fossil range: Early Pleistocene

Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Subfamily: Homininae
Genus: Homo
Species: H. antecessor
Binomial name
Homo antecessor
Bermudez de Castro et al., 1997

Homo antecessor is an extinct hominin and a potential distinct species dating from 1.2 million to 800,000 years ago, that was discovered by Eudald Carbonell, J. L. Arsuaga and J. M. Bermúdez de Castro. H. antecessor is one of the earliest known hominins in Europe; only those individuals from the site of Dmanisi, Georgia, are older. Many anthropologists believe that H. antecessor is either the same species or a direct antecedent to Homo heidelbergensis, who inhabited Europe from 600,000 to 250,000 years ago in the Pleistocene. It is suggested that this is the last common ancestor of Homo neanderthalensis and Homo sapiens.

The best-preserved fossil is a maxilla which belonged to a 10-year-old individual found in Spain. Based on palaeomagnetic measurements, it is thought to be older than 780-857 ka (Falguères et al., 1999:351). The average brain was 1000 cm³ in volume. In 1994 and 1995, 80 fossils of six individuals that may have belonged to the species were found in Atapuerca. At the site were numerous examples of cuts where the flesh had been flensed from the bones, which indicates that H. antecessor could have practised cannibalism.[1]

Contents

[edit] Physiology

Homo antecessor was about 1.6-1.8 m (5½-6) feet tall, and males weighed roughly 90 kg (200 pounds). Their brain sizes were roughly 1000-1150 cm³, smaller than the 1350 cm³ average of modern humans. Due to its scarcity, very little more is known about the physiology of H. antecessor, yet it was likely to have been more robust than H. heidelbergensis. According to Juan Luis Arsuaga, one of the co-directors of the excavation in Burgos, e H. antecessor might have been right-handed, a trait that makes him different from the rest of apes. The hypothesis is based on tomography techniques. Arsuaga also claims that the frequency range of audition is similar to H. sapiens' which makes him believe that H. antecessor used a symbolic language and was able to reason.[2] Arsuaga's team is currently pursuing a DNA map of H. antecessor after elucidating that of a bear that lived in northern Spain some 500,000 years ago.

Basing on teeth eruption pattern, the researchers think that Homo antecessor had the same development stages as Homo sapiens, though probably at a faster pace. Other features acquired by the species are a protruding occipital bun, a low forehead and a lack of a chin. Some of the remains are almost indistinguishable from the fossil attributable to KNM-WT 15000 (Turkana Boy) belonging to Homo ergaster.

[edit] Fossil sites

The only known fossils of H. antecessor are from two sites in the Sierra de Atapuerca region of northern Spain (Gran Dolina and Sima del Elefante). The sites in this area have been found during the construction of railway cuts (Gran Dolina, Galería, Elefante) and in a cave (Sima de los Huesos). Sites in the area have also yielded stone artefacts.

[edit] Gran Dolina

Archaeologist Eudald Carbonell i Roura of the Universidad Rovira i Virgili in Tarragona, Spain and palaeoanthropologist Juan Luis Arsuaga Ferreras of the Complutense University of Madrid discovered Homo antecessor remains at the Gran Dolina site in the Sierra de Atapuerca, east of Burgos. The H. antecessor remains have been found in level 6 (TF6) of the Gran Dolina site . Over 80 bone fragments from six individuals were uncovered in 1994 and 1995. The site had also included roughly 200 stone tools and about 300 animal bones. Stone tools including a stone carved knife were found along with the ancient hominin remains. All these remains were dated at least 780,000 years old. The best-preserved remains are a maxilla (upper jawbone) and a frontal bone of an individual who died at 10-11 years old.

[edit] Sima del Elefante

On 2007-06-29, Spanish researchers working at the Sima del Elefante site announced that they had recovered a molar dated to 1.1–1.2 million years ago. The molar was described as "well worn" and from an individual between 20 and 25 years of age. Additional findings announced on 2008-03-27 included the discovery of a mandible fragment, stone flakes, and evidence of animal bone processing.[3]

[edit] References

  1. ^ Fernández-Jalvo, Y.; Díez, J. C.; Cáceres, I. and Rosell, J. (September 1999). "Human cannibalism in the Early Pleistocene of Europe (Gran Dolina, Sierra de Atapuerca, Burgos, Spain)". Journal of Human Evolution 37 (34): 591-622. Academic Press. doi:10.1006/jhev.1999.0324. ISSN 0047-2484. 
  2. ^ El Mundo newspaper (in Spanish)
  3. ^ Carbonell, Eudald; José M. Bermúdez de Castro et al (2008-03-27). "The first hominin of Europe". Nature 452: 465-469. doi:10.1038/nature06815.