Hominid Evolution
Hominid Evolution
The evolution of hominids has been and still is a heated topic of debate. Many scientists
debate over which species can be classified as “human”. The root "hominid" refers to members
of the family of humans, Hominidae, which consists of all species on our side of the last
common ancestor of humans and living apes. The time split between humans and living apes
used to be thought of fifteen to twenty millions of years ago, but now the time period has shifted
to around five million years ago.
Ardipithecus ramidus is said to have live around 4.4 million years ago. The original
fossils from this species were placed with the Australopithecus genus; however, a new genus was
designated to this group by Tim White. Tim White is an anthropologist and co-author of
Geological Study of America Bulletin in which this distinction was first stated. This hominid is
different from its predecessors because it lacks an incisor tooth, yet posses an ape-like molar
structure. Another major defining characteristic of A. ramidus is that the cranial bones that have
been discovered reveal this hominid walked on four appendages rather that the more developed
species which walked on two.
The next hominid in line is Australopithecus anamensis. This hominid lived for the
period of 3.5-4.17 million years ago. It was discovered by a Harvard Expedition to the East Lake
Turkana in 1995. The classification of A. anamensis was done after extensive research by Meave
Leakey and associates. The skeletal structure of this hominid reveals that it was bipedal
(walking on two legs) which distinguishes it distinctly from A. ramidus. However, A. anamensis
possessed some traits that were similar to hominids before it such as a dental structure that is
similar to that of an ape and an ape-like skull. On the other hand, this hominid has an unique
thick tooth enamel and expanded molars.
Between 3.9 and 3.0 million years ago, Australopithecus
The evolution of hominids has been and still is a heated topic of debate. Many scientists
debate over which species can be classified as “human”. The root "hominid" refers to members
of the family of humans, Hominidae, which consists of all species on our side of the last
common ancestor of humans and living apes. The time split between humans and living apes
used to be thought of fifteen to twenty millions of years ago, but now the time period has shifted
to around five million years ago.
Ardipithecus ramidus is said to have live around 4.4 million years ago. The original
fossils from this species were placed with the Australopithecus genus; however, a new genus was
designated to this group by Tim White. Tim White is an anthropologist and co-author of
Geological Study of America Bulletin in which this distinction was first stated. This hominid is
different from its predecessors because it lacks an incisor tooth, yet posses an ape-like molar
structure. Another major defining characteristic of A. ramidus is that the cranial bones that have
been discovered reveal this hominid walked on four appendages rather that the more developed
species which walked on two.
The next hominid in line is Australopithecus anamensis. This hominid lived for the
period of 3.5-4.17 million years ago. It was discovered by a Harvard Expedition to the East Lake
Turkana in 1995. The classification of A. anamensis was done after extensive research by Meave
Leakey and associates. The skeletal structure of this hominid reveals that it was bipedal
(walking on two legs) which distinguishes it distinctly from A. ramidus. However, A. anamensis
possessed some traits that were similar to hominids before it such as a dental structure that is
similar to that of an ape and an ape-like skull. On the other hand, this hominid has an unique
thick tooth enamel and expanded molars.
Between 3.9 and 3.0 million years ago, Australopithecus