Hominid Evolution


Distinguishing features and characteristics





This chart of the Hominid family will categorize the known hominids by genus and species, and if applicable, the subspecies or other categorization. Beginning with the oldest known species and moving forward chronologically, it will give their age by oldest and youngest confirmed or conjectured date (as noted),the creatures known locations and environments, its distinguishing physical characteristics, any technology it may or is known to have posessed, and any social behaviours that are known or can be ascribed. Conjecture about the species and their relationships to others will be included. Finally some notable archeological sites or finds will be given.

Each paragraph of facts will be provided with source citations.

Due to size limitations, this survey is presented in two parts.


Part 1

Early Primates

In the Late Cretaceous, 70 mya, two varieties of primates existed: the Strepsherinni, a nocturnal beastiary, and the Haplorini, a diurnal variety, from which hominids arose. (1)

Hominoid Superfamily
This group contains species that would later develop into the hominid line and the great apes. (1)

Aegyptopithecus
Found in the later Oligocene, 28-29 mya, in Egypt, and having a somewhat developed forehead, small incisors, lower premolars and large molars. (1)

Proconsul
Three species; major, africanus and nyanzae, all showing hominid characteristics. (1)

Kenyapithecus wickeri
A possible forerunner of the Pongid and Hominid lines. (1)

Hominids

Climatic cooling during Late Miocene (6.0 to 5.3 mya) probably triggered speciation of Hominoid super-family into the Hominid family, along with other mammalian speciations. (2) A Gap in Hominoid fossil record from 14 mya to 4.2 mya leaves these questions unanswered for the time being. (3)

Ardipithecus ramidus
4.4 mya (4)
Hominoid/hominid teeth. A piece of the forenum magnum indicated upright posture. (4) Leg and pelvis indicate a semi-bipedal mode of locomotion, warranting a separate genus. (5)
In Ethiopia, the remains of 17 individuals have been found, mostly teeth, but a partial juvenile jaw, partial cranum case and arm bone fragments from two individuals are included. The envorinment at the time was temperate or tropical forest. Discovered by Tim White in 1994. (4, 6)

Australopithecines
General:
The Lake Baringo jawbone could make this genus 5 million years old. (3) Human-like jaws and teeth, ape-like (small) skull. (3) Gracile. Bi-pedal, but still tree climbers. Pronounced cheekbones, projecting jaws, large teeth, heavily enameled molars that indicate a primarily vegetarian diet. A high degree of sexual di-morphism. (9) Their remains have been found only on the African continent (3) .

A. anamensis
4.2 to 3.5mya (10)
A thick tibia with a concave knob on top indicates bi-pedalism. Paralell rows of back teeth are similar to apes, likewise its small earholes. (5)
Found only in East Africa so far, possibly forest dwelling. (5) A lower left humerous (4 mya), lower jaw with all teeth (4.15 mya), and the upper and lower segments of a tibia (4 mya) were discovered by Meave Leaky in 1995 around Lake Turkanna, Nairobi, Kenya. (10, 1)

A. afarensis
5 mya to 3 mya. (3)
400cc braincase. (9) Arms longer than humans but shorter than modern apes. About four feet tall. (3) Veinous brain cooling mechanism, modified from non-erect hominoids. (7)
Could have lived in African forests or savannah, or both, with tree climbing abilities. (12, 7)
Some found in groups. (6)
A knee joint (3.4 mya), the Lucy skeleton, and the First Family of thirteen individuals (3.2 mya) were discovered in the Afar valley, Ethiopia by Donald Johansen in 1973, 74 and 75, respectively. Footprints (3.7 mya) preserved in volcanic ash at Laetoli, Kenya and discovered by Mary Leaky in 1976 may belong to this species. In 1991, a 70% complete skeleton was discovered by Bill Kimbel and Yoel Rak, and confirmed the skeletons and skull’s belonged to the same species and confirmed the dimorphism of the species. (6)
Associated with an ape-like, grasping big toe found on two fully articulated feet and ankle fossils, dated 3.5mya. The pieces were discovered by Ronald Clarke in a university museum drawer in Johannesburg, having been dug up from a mine shaft in the 70’s and mislabled as chimpanzee’s. (12)

A. africanus
http://anthro7.anthro.uiuc.edu/~anth102/sts_5.html 3 mya (3) to 1 mya (?)
Gracile variety. (3) Modified veinous brain cooling. (7) 440 to 485cc braincase capacity. (6)
“Taung Child”, identified by Ramond Dart in 1925 and rejected by other anthropologists as a human predecessor, is about 1 to 2 mya (most scientists expected a large-brained ancestor with an ape like jaw, and seemed to want to reject in any event an African genesis of human evolution). The foramen magnum at the base of the skull indicated bipedalism.
At Mankapan, South Africa, Dart discovered the most complete Australopithecus to that date, 1958. He named it “Plesianthropus”. It was an africanus specimen, and dated 2.3 mya. (8, 6)

Paranthropus
General:
Formerly classified as a robust form of Australopithecus. (3) Masive teeth and jaw muscles indicate vegetarian diet of coarse plant material. (2) Recent examinations of its hand bones reveal that it could have manipulated stone tools quite well. (31)
African continent, tropical forest dwelling. (2, 7)
Stone tools have turned up in Ethiopia that have been dated to 2.5 to 2.6 mya, the oldest ones discovered so far. This makes the arrival and departure of the Oldowan tool industry coincident with the tenure of the Paranthropus species, and from this some now suggest that it was Paranthropus, and not early Homo, that were the first tool makers. (31)

Enlarged sinus brain cooling mechanism, derivative from Autralopithecines. (7)

P. aethiopicus
3.3 to 2.6 mya (33)
Suspected progenitor of the paranthropus genus. (31)
The Black Skull of Tanzania was discovered by Alan Walker in 1985, and is now considered by some a member of this species. (33)

P. boisei
2,6mya (3) to 1.2 mya (2) .
Largest variety. Sometimes with bony crests atop their skulls supporting massive jaw muscles. Smallest hominid braincase recorded (410cc). More prominent ridges, more jutting face. (3)
A complete intact cranium missing only teeth, with a braincase of about 510cc and dated 1.7 mya, discovered by Richard Leaky in 1969, near Lake Turkana. A smaller version without the bony crest, dated to 1.7 mya and with a 500cc braincase was discovered by the same Leaky in the same area in 1970. (6)

P. robustus
2.6 mya to 1.8 mya (3, 31)
“Zinjanthropus” or “Nutcracker Man”, an almost complete cranium with a 530cc capacity, was discovered by Mary Leaky in 1959 at Oldavai Gorge in Tanzania, dated to 1.8 mya. (8, 6) Once classified as A. boisei. (3)

End of Part One


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Please see the Hominidography if you wish to help me update this treatise, especially with the incomplete citations.
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