Hominids

The hominids are a type of primates characterized by upright posture and the bipedalism. Among the hominids today are the humans and their close relatives, orangutans, gorillas, chimpanzees and bonobos.

Hominids have diversified over time, originating different genera and species, many of which coexisted in the same space.

When the primates had to leave the trees and go down to the ground, they became more vulnerable, so the appearance of bipedalism was a very advantageous feature, since it allowed them to see their surroundings better and see if there were predators. In addition, having their hands free allowed them to manipulate objects, which was also a great advantage over other competing species. The manipulation of objects caused the brain to increase in size , since it requires a lot of cerebral cortex, and to develop intelligence, emotions and the ability to speak.

The main characteristic of the genus Homo is the presence of an opposable thumb that allows it to manipulate instruments, and a developed brain that coordinates the movements of the muscles so that they can perform precise movements. The brain is larger and, above all, it has many folds (convolutions) that allow to have a large surface of the cerebral cortex in a not too large volume.

The main hominids that have existed throughout history before reaching Homo sapiens have been:

• Ardipithecus ramidus.
• Australopithecus.
• Homo habilis.
• Homo ergaster.
• Homo erectus.
• Homo antecessor.
• Homo heidelbergensis.
• Homo neanderthalensis.
• Homo sapiens.

Interactive activity: Order the processes that led to the appearance of the genus Homo.

Ardipithecus ramidus

The first known hominin lived in the Ethiopia area about 5 million years ago. Its name, "Ardi", means soil, "ramid", root, in Amharic (language of the place where the fossil remains were found), and "pithecus" means monkey, in Greek. Therefore, its name indicates that it is a "monkey that is at the root of our tree". It is not clear that it was bipedal. His face and brain were small.

Ardipithecus ramidus was similar to a chimpanzee, lived in wooded areas and fed on fruits and young shoots of leaves. It seems that when it was adapting to less wooded areas of the savannah, 4 million years ago, it originated another type of hominin, the Australopithecus.

Australopithecus

The name Australopithecus comes from "Australo", which means " from the south ", and "pithecus", which means "monkey", so Australopithecus means "southern monkey".

Several different species of Australopithecus are known. Although the oldest species is Australopithecus anamensis (4.5 - 4 million years old), the best known species Australopithecus afarensis , to which belongs the skeleton, found in 1974, of a 1.1 meter female to whom They named it Lucy, our most famous ancestor between 3.2 and 3.5 million years old.

The brain of Australopithecus was small, about 500 cm³, similar to that of chimpanzees. They still climbed trees, but they were already bipeds even though they did not walk upright for a long time. The males (1.50 meters) were taller than the females (1 meter), and their diet was vegetarian. They did not make tools, and their hands and feet were already quite similar to those of modern humans.

Remains of Australopithecus garhi (2.5 million years old) have been found along with other remains of animals with traces of having been cut, so it seems that the more modern Australopithecus would also include meat in their diet, perhaps they were scavengers.

By Nachosan (Own work) [CC BY-SA 3.0], via Wikimedia Commons

Australopithecus were spreading through the savannah of East Africa, originating two evolutionary lines:

• Paranthropes. Large, vegetarian hominids with broad bones and very powerful facial muscles that allowed them to chew hard roots and seeds. The parántropos include Paranthropus (Australopithecus) boisei and Paranthropus (Australopithecus) robustus.
  
• Australopithecus africanus. Hunter and carnivore. It would later give rise to the genus Homo, which includes all the direct ancestors of the human being. They are characterized by the ability to make tools, which differentiates them from other animals.

Video: Lucy In The Sky With Diamonds (The Beatles).

Homo habilis

The Homo habilis lived in Africa, from 2.4 to 1.6 million years ago. Their name means skillful man because they were capable of making stone instruments. These tools were very simple, and they were built by hitting some stones with others, abandoning them after using them.

It lived in the African savannah and it seems that it was an omnivore and a scavenger. Later, he would become a hunter.

The cranial capacity of Homo habilis is about 650 cm³, considerably greater than that of Australopithecus. Their jaws were quite large compared to their skull.

It is possible that they already used rudimentary language.

By unknown (klimaundmensch.de)derivative work: Sargoth (talk)Homo_habilis.JPG: Photographed by User:Lillyundfreya (Homo_habilis.JPG) [CC BY-SA 2.5-2.0-1.0, GFDL or CC-BY-SA-3.0], via Wikimedia Commons

Homo ergaster

Homo ergaster  lived in Africa between 1.8 and 1.4 million years, although it was the first hominid to leave Africa:

• Homo ergaster would evolve, in Asia, originating Homo erectus.
• Homo ergaster would evolve, in Africa, originating Homo antecessor.

Its cranial capacity was 900-1000 cm³, and it is considered the first modern hominid. They were larger than Homo habilis (between 1.50 and 1.80 meters), and their face was more similar to that of a modern human.

They hunted herbivores and made better tools (biface, picks, scrapers, splitters, etc.) that they kept and carried with them.

They acquired a more complex language.

Homo erectus

The name Homo erectus comes from erect, and refers to a group of Asian hominids that arose from Homo ergaster (Africa) that lived between 1.9 million years ago and 70,000 years ago. They were good hunters.

In addition to its natural upright posture, it was characterized by having a larger brain (between 850 and 110 cm³) and a smaller jaw.

They were omnivores, they dominated fire and made more elaborate tools.

By klimaundmensch.de[ (author of reconstruction unknown)Homo_erectus.JPG: photographed by User:Lillyundfreyaderivative work (crop operation): Rafaelamonteiro80 (Homo_erectus.JPG) [CC BY-SA 2.5-2.0-1.0, CC-BY-SA-3.0 or GFDL], via Wikimedia Commons

Homo antecessor

The cranial capacity of Homo antecessor is 1000 cm³, and you have human like features. They are between 900,000 and 1,200,000 years old.

Their height was 1.60-1.85 meters, and they weighed between 60 and 90 kilos. They made rudimentary tools. They were omnivores, and there are remains that prove that they were also cannibals, it is not known whether as food or by some ritual. His face was similar to that of modern human beings.

It has been found in the Atapuerca deposit, in Burgos. Although remains have only been found in Europe, it is believed that he may have emigrated from Africa, although espinning differently on each continent.

• In Europe, Homo antecessor evolved into Homo heidelbergensis and Homo neanderthalensis.
• In Africa, it would evolve to Homo sapiens.

Homo heidelbergensis

Homo heidelbergensis arose from Homo antecessor, and lived only in Europe 600,000-200,000 years ago.

Its cranial capacity was about 1,350 cm³, with protruding jaws and a large nasal opening. They could measure up to 1.75 meters tall and were very strong, weighing up to 105 kg.

They were omnivores. They made specialized tools. They knew how to make fire. Since the weather was cold, they dressed in furs. They buried the dead and buried them with some kind of ritual. There are already hints of symbolic thinking.

It evolved rapidly with climate change that led to a new ice age, originating Neanderthal man (Homo neanderthalensis).

By Tim Evanson [CC BY-SA 2.0], via Wikimedia Commons

Homo neanderthalensis

During the ice age, Homo heidelbergensis gave rise to Homo neanderthalensis, the Neanderthal man. It lived between 230,000 and 28,000 years ago. It is also known as Homo sapiens neanderthalensis, sapiens for intelligent and neanderthalensis, for the place where it was discovered.

His height was approximately 1.65 meters, and his weight was about 75 kg.

It was adapted to a cold climate, with little vegetation and fauna adapted to that climate. He was a good hunter of those animals. He built much more precise tools. He was a good hunter who cared for his children, the elderly, and buried the dead.

It had a very large cranial capacity (1500 cm³), similar to that of modern humans. Homo Neanderthal was the most human hominid that had existed until then, with a fairly developed communication capacity between individuals, although it could not with the competition that came from Africa from another species, Homo sapiens. It was disappearing from Europe as Homo sapiens spread.

Por Stefan Scheer (Trabajo propio) [GFDL, CC-BY-SA-3.0 undefined CC BY 2.5], undefined

Homo sapiens

Homo antecessor, in Africa, in a very different environment in which Homo heidelbergensis and Homo neanderthalensis lived, gave rise to another different species, Homo sapiens.

They lived between 150,000 and 100,000 years ago. The oldest fossils were found in Ethiopia, although they colonized all the continents in a few thousand years, occupying all ecosystems and displacing the other hominid species with which it could coexist. They were similar to human beings today.

Interactive activity: Order the hominid species chronologically.

Interactive activity: Match each skull with the corresponding hominid species.

Interactive activity: Match each hominid with its characteristic.

Interactive activity: Chronologically order these events of the hominization process.

Interactive activity: Test on the hominization process.