Significance of Hominin Species Flashcards
Sahelanthropus tchandensis
7-6 mya (CA). May be the earliest hominin in the fossil record; it is hotly debated whether it truly is.
Ardipithecus ramidus
4.4-3.9 mya (EA). Morphology indicates that Ardipithecus ramidus was a facultative upright walker that was a competent tree climber. The fact that it lived in a forested area puts an end to the savannah hypothesis.
Au. anamensis
4.2-3.9 mya (EA). While some consider anamensis and afarensis to be one and the same, anamensis has more primitive dentition than afarensis and thus may be two species. The first Australopithecine in the record.
Au. afarensis
4-3 mya (EA). The presence of both bipedal evidence and curved fingers and toes has set of a debate about whether this species was a habitual biped or a biped or a climber. Lucy is a significant find of this species. She indicates a clear mosaic of human and apelike features
K. platyops
3.5-3.2 mya (EA). This specimen threw the accepted timeline off because it has a flat face. Although it is older than Lucy, it has less evolutionarily primitive traits. Meave Leaky has argued that it was possible that Kenyapithecus was the human ancestor, and that Australopithecus was a side branch
Au. bahrelghazalia
3.5-3 mya (CA). Looks like Lucy. It extends the range of australopithecines because it was found in CA.
Au. africanus
3-2 mya (SA). Important find: the Taung child. Finds alongside the fossils indicate that they lived in woodland and open woodland environments. This has led to a recent debate about extent of climbing activity. Dating is more difficult in South Africa because there is no ash.
Au. garhi
2.5 mya (EA). Animal remains with cut and percussion marks found near the specimens indicate possible tool use.
Australopithecus/Paranthropus aethiopicus
2.8-2.2 mya (EA). A good candidate for the ancestor of Au. boisei and robustus. It has masticatory characters of the robust forms but some primitive traits from an earlier hominin such as afarensis. Others contend that it is possible that the South and East African robust forms are look the same because of convergent evolution to diet.
Australopithecus/Paranthropus boisei
2.3-1.2 mya (EA). Boisei is the most specialized robust australopithecine. Shares some traits with aethiopicus that are not shared with robustus. This has led some to put aethiopicus and boisei in one lineage, and robustus in another. The question is whether they are actually closely related on the phylogenic tree or they simply resemble one another.
Australopithecus/Paranthropus robustus
2-1 mya (SA). Studies suggest that robustus ate a substantial amount of animal protein. Au. robustus probably ate termites, as indicated by wear patterns on the ends of animal bones.
Au. sediba
1.98 mya (SA). The discoverers of the species have argued that some Homo-like characteristics imply a relation between sediba and Homo, perhaps even Homo erectus.
H. habilis
2.33-1.44 mya (EA & SA). There were tools found alongside Homo habilis: definitive stone tool manufacture. It used to be thought that only humans could make tools. Their toolmaking tradition was Oldowan, their technique was hard hammer percussion, their characteristic tool was a chopper and unretouched flakes, and the cultural period was the Lower Paleolithic [2.6 mya-200 kbp]. Evidence for man the scavenger, not man the hunter as tool marks were above predator gnaw marks on bones.
H. erectus
1.8-.1 mya (Africa, Asia, Europe). The first find was at Java; subsequent ones were in Zhoukoudian and Olduvai Gorge. Redating found the Indonesian finds at 1.8 million years ago – apparently dispersion from Africa happened at a very fast pace. An important find, the Turkana boy, showed that the species had longer legs than arms, and was taller than Homo habilis with a basically modern human body plan.
Transitionals/H. heidelbergensis
.8-.2 mya. Are these specimens Archaic Homo sapiens or Homo heidelbergensis? The problem is that there is variability within heidelbergensis that causes overlap between Homo sapiens and Homo heidelbergensis. For this reason they are compared both with AMHs and Neandertals. An important find was Bodo in East Africa, whose face was defleshed (this is apparent because of cuts inside his eye sockets). Was he a product of cannibalism or something else? Homo heidelbergensis made Achulean hand axes and retouched flakes with hard and soft percussion techniques during the Lower Paleolithic. We used to think that was it, but recently blades have been found. This is huge, as it moves blade technology from 40 kbp to 400 kbp. Spear shafts were also found in Germany. They cared for the sick, as evidenced by an individual at Atapuerca who lived until 10 or 11 with a cranial disease that prevents growth. This would have been impossible unless he/she was cared for.
