Homo sapiens idaltu: characteristics of this possible human subspecies

Throughout the history of paleoanthropology, all kinds of bones have been found, both from primitive humans as species from which we are either descended or evolved in parallel to ours but are extinguished.

However, the bones of the Homo sapiens idaltu, human remains found in Ethiopia, seemed to be proof of a missing link between extinct humans and current humans, although generating a real controversy in the scientific community.

Let's see next who were these hominids and why so much controversy was generated.

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what is the Homo sapiens idaltu?

He Homo sapiens idaltu, also known as Herto man, was, according to the current point of view of the scientific community, a subspecies of Homo sapiens. The remains of this hominid were found in Ethiopia in 1997 and, although they are considered to belong to our species, the remains had some morphological characteristics that made them significantly different from how current humans are, but not enough to consider them a separate species.

The scientific name of this species, Homo sapiens idaltu, as you can see is trinominal. In taxonomy trinominal names are used to refer to subspecies, the two words being the genus and the specific name of the species, while the third word refers to its subspecies. In this case, Homo refers to hominids, "sapiens" to the fact that it is part of the human species (sapiens in Latin means wise) and idaltu is a word in Amharic, the language of the region where it was discovered, which means "old man".

Discovery

He Homo sapiens idaltu It was discovered in Herto Bouri, which is why it is colloquially called a man from Herto. This region is in Ethiopia, near the Middle Awash in the Afar Depression, areas characterized by having underlying layers of volcanic origin, dating back between 154,000 and 160,000 years.

The find was made in 1997 by the team of paleoanthropologists Tim White, Berhane Asfaw and Giday WoldeGabriel, scientists at the University of California at Berkeley and the Natural History Museum of London. Despite the fact that the discovery was made in the 1990s, the discovery would be made public several years later, in 2003., after making sure that they had indeed found a new type of hominid but within the human species.

These remains correspond to the skulls of three individuals, two male adults and one child. The age of these skeletal remains is 158,000 years, living in the Chibaniense or Middle Pleistocene prehistoric period. His finding was really important, since until then there was a gap in the human fossil record, missing intermediate fossils between prehumans and modern humans, in the period from 300,000 to 100,000 before our era.

The remains of the Homo sapiens idaltu they were considered to be the oldest specimens of the Homo sapiens species until 2005. In that year the fossils Omo I and Omo II were found, remains of Homo sapiens oldest, dating back 195,000 years. Subsequently, in 2017, human fossils were discovered in Morocco in Jebel Irhoud, dating back 315,000 years.

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Morphology and taxonomy

The remains of the Homo sapiens idaltu differ from chronologically later forms of the earliest Homo sapiens. In fact, the men of Herto possess traits reminiscent of other hominid species found in Africa.

The three skulls found closely match the shape of the modern Homo sapiens skull, especially the globular shape of the skull and face. Even so, they have distinctive features that have led them to be considered a different subspecies from ours. These traits are visible in the browbone, in addition to having a more robust build and a highly projected occipital protuberance..

One of the features that makes them stand out is that they do not present prognathism, something common in Neanderthals. This made the experts confirm that these remains did not belong to the homo neanderthalensis. This gave strength to the idea that the first sapiens evolved in Africa long before European Neanderthals disappeared, refuting the idea of ​​the "Neanderthal phase" in evolution human.

The conclusion before the finding is that they are a transition from the most primitive African hominids to modern human beings. Based on traits, the scientific community considers the Homo sapiens idaltua subspecies of Homo sapiens extinct, which must have been our direct ancestors of the current human species, defending the idea of ​​recent African origin theory.

Next we will see in a little more detail the morphological characteristics of these three skulls.

BOU-VP-16/1

It is an almost complete skull of an adult, with a cranial capacity of about 1450 cubic centimeters. This is truly amazing, since that cranial capacity is superior to many of modern humans.

BOU-VP-16/2

It corresponds to another adult skull, although not as complete as the first. Its size could be even larger than the previous one.

BOU-VP-16/5

This skull is that of a child. He must have been between 6 or 7 years old, estimated from the teeth, with a cranial capacity of 1250 cubic centimeters. It was fragmented into more than 200 pieces, and painstaking reconstruction was required to analyze it.

Controversy

The discovery of this hominid subspecies sparked controversy among researchers in the field of paleontology. Critical voices considered that the Homo sapiens idaltu He was just a normal human being. like those of the present species of Homo sapiens, but which possessed some archaic morphological trait.

That feature, compared to that of other fossils of Homo sapiens, led to think that it was a different subspecies, when perhaps in reality they simply presented some difference. An example of remains of Homo sapiens with striking features are Cro-Magnon men and Grimaldi men, but these hominids are not considered subspecies of sapiens.

It should be said that the scientific community has problems establishing when two populations are two different subspecies. Morphological traits may not be sufficiently different to state that two individuals are not part of the same evolutionary lineage.. In fact, the same thing was observed by Chris Stringer in 2003, when the discovery of Homo sapiens idaltu came to light. Stringer said in an article in the journal Nature that the skulls did not appear to possess features so different as to make Herto Man a subspecies of Homo sapiens.

To this day, and despite the fact that the trinomial name and the idea that it is a subspecies have been preserved, there is still debate. In fact, the use of this name is controversial given that, if the thesis according to which the Homo sapiens idaltu is a subspecies of ours, we should rescue the old denomination of Homo sapiens sapiens to refer to actual human individuals.

The term Homo sapiens sapiens it was used in the past when Neanderthals were thought to be a human subspecies rather than a different hominid species from ours. Similarly, it should be said that the claim that humans and Neanderthals are different species continues to be debated, given that has verified that when both types of hominids coincided in evolutionary history, there were crosses that gave rise to hybrids fertile. In fact, the European population has Neanderthal genes in its genotype.

Bibliographic references:

• Smith, Fred H.; Ahern, James C. (2013). The Origins of Modern Humans: Biology Reconsidered. John Wiley & Sons. ISBN 978-1-118-65990-8.
• White, Tim D.; Asfaw, Berhane; DeGusta, David; Gilbert, Henry; Richards, Gary D.; Suwa, Gene; Clark Howell, F. (2003). Pleistocene Homo sapiens from Middle Awash, Ethiopia. Nature 423 (6941): 742-747.
• Stringer, Chris (2003). «Human evolution: Out of Ethiopia». Nature 423 (6941): 693-695.