The
evolution from ape to man has always been a mystery. Some experts
speculate that there is a "missing link" between humans and apes, like a
new species of ape that completely removed itself from the trees and
began to walk upright throughout the plains. Other experts believe that
the change was much more gradual and complicated than we have ever
imagined. It seems that the latter experts might
have been correct.
In 1974, a hominid nicknamed Lucy (Australopithecus afarensis) was
discovered at Hadar in the Awash Valley of Ethiopia's Afar Depression.
Lucy is thought to have lived around 3.2 million years ago, and her
ape-like head and her human-light stature proved to be an important
discovery in the hunt for humanity's ancestors. In 2000, a toddler
specimen of Australopithecus afarensis was discovered in Ethiopia's
Great Rift Valley. Although the hominid fossil dates back tens of
thousands of years older than Lucy, scientists nicknamed the baby
skeleton "Lucy's baby," since the fossil is more complete and gives us a
better understanding of their anatomy. The baby hominid, later renamed
Selam, proved to scientists that A. afarensis had not progressed beyond
great apes at all; their intellect and brain size remained about the
same, but their locomotion had changed, perhaps to fill a different
niche outside of the forest.
So, is Australopithecus afarensis
the absolute "missing link" when early humans stood upright and ran far
from their protective forests? Not exactly. Although A. afarensis had
legs capable of walking upright, they retained certain ape-like traits
from the waist up. Zeresenay Alemseged, curator of anthropology at the
California Academy of Sciences, and David Green, an assistant professor
in the Department of Anatomy at Midwestern University, noticed that A.
afarensis had the shoulder blades of an ape, and was completely capable
of swinging from tree to tree. This means that Lucy, Selam, and their
fellow kin were capable of living an arboreal lifestyle, perhaps to nest
in trees or evade predators, as well as walking and running far
distances on their hind legs. Thus, our ancestors did not quickly
abandon their ape-like characteristics for bipedal locomotion...
instead, these changes were gradual, and reflected adaptations to a wide
variety of habitats. As our ancestors began to learn to use tools with
their free forelimbs, they had better means to protect themselves from
predators and survive. But until then, hominids like Lucy and Selam
continued to take advantage of their ancestral ape characteristics to
survive.
Sources:
http://news.discovery.com/
http://
Image credit: nationalgeographic.com
The
evolution from ape to man has always been a mystery. Some experts
speculate that there is a "missing link" between humans and apes, like a
new species of ape that completely removed itself from the trees and
began to walk upright throughout the plains. Other experts believe that
the change was much more gradual and complicated than we have ever
imagined. It seems that the latter experts might
have been correct.
In 1974, a hominid nicknamed Lucy (Australopithecus afarensis) was discovered at Hadar in the Awash Valley of Ethiopia's Afar Depression. Lucy is thought to have lived around 3.2 million years ago, and her ape-like head and her human-light stature proved to be an important discovery in the hunt for humanity's ancestors. In 2000, a toddler specimen of Australopithecus afarensis was discovered in Ethiopia's Great Rift Valley. Although the hominid fossil dates back tens of thousands of years older than Lucy, scientists nicknamed the baby skeleton "Lucy's baby," since the fossil is more complete and gives us a better understanding of their anatomy. The baby hominid, later renamed Selam, proved to scientists that A. afarensis had not progressed beyond great apes at all; their intellect and brain size remained about the same, but their locomotion had changed, perhaps to fill a different niche outside of the forest.
So, is Australopithecus afarensis the absolute "missing link" when early humans stood upright and ran far from their protective forests? Not exactly. Although A. afarensis had legs capable of walking upright, they retained certain ape-like traits from the waist up. Zeresenay Alemseged, curator of anthropology at the California Academy of Sciences, and David Green, an assistant professor in the Department of Anatomy at Midwestern University, noticed that A. afarensis had the shoulder blades of an ape, and was completely capable of swinging from tree to tree. This means that Lucy, Selam, and their fellow kin were capable of living an arboreal lifestyle, perhaps to nest in trees or evade predators, as well as walking and running far distances on their hind legs. Thus, our ancestors did not quickly abandon their ape-like characteristics for bipedal locomotion... instead, these changes were gradual, and reflected adaptations to a wide variety of habitats. As our ancestors began to learn to use tools with their free forelimbs, they had better means to protect themselves from predators and survive. But until then, hominids like Lucy and Selam continued to take advantage of their ancestral ape characteristics to survive.
Sources:
http://news.discovery.com/
http://
Image credit: nationalgeographic.com
In 1974, a hominid nicknamed Lucy (Australopithecus afarensis) was discovered at Hadar in the Awash Valley of Ethiopia's Afar Depression. Lucy is thought to have lived around 3.2 million years ago, and her ape-like head and her human-light stature proved to be an important discovery in the hunt for humanity's ancestors. In 2000, a toddler specimen of Australopithecus afarensis was discovered in Ethiopia's Great Rift Valley. Although the hominid fossil dates back tens of thousands of years older than Lucy, scientists nicknamed the baby skeleton "Lucy's baby," since the fossil is more complete and gives us a better understanding of their anatomy. The baby hominid, later renamed Selam, proved to scientists that A. afarensis had not progressed beyond great apes at all; their intellect and brain size remained about the same, but their locomotion had changed, perhaps to fill a different niche outside of the forest.
So, is Australopithecus afarensis the absolute "missing link" when early humans stood upright and ran far from their protective forests? Not exactly. Although A. afarensis had legs capable of walking upright, they retained certain ape-like traits from the waist up. Zeresenay Alemseged, curator of anthropology at the California Academy of Sciences, and David Green, an assistant professor in the Department of Anatomy at Midwestern University, noticed that A. afarensis had the shoulder blades of an ape, and was completely capable of swinging from tree to tree. This means that Lucy, Selam, and their fellow kin were capable of living an arboreal lifestyle, perhaps to nest in trees or evade predators, as well as walking and running far distances on their hind legs. Thus, our ancestors did not quickly abandon their ape-like characteristics for bipedal locomotion... instead, these changes were gradual, and reflected adaptations to a wide variety of habitats. As our ancestors began to learn to use tools with their free forelimbs, they had better means to protect themselves from predators and survive. But until then, hominids like Lucy and Selam continued to take advantage of their ancestral ape characteristics to survive.
Sources:
http://news.discovery.com/
http://
Image credit: nationalgeographic.com
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