BIOREVISION ESSAY
Human Divergence Fluctuated with Climate
It has long been thought by biologists that our physical features, such as our large brains, long legs, the ability to make and use tools, as well as our prolonged maturation periods had all evolved together in the beginning of the Homo lineage (1). This was a period of time when the African grasslands began to expand and the Earth 's climate cooled and became much drier (1) (2). Although scientists have recognized and known these traits to be specific to humans, which were thought to have originated in the genus Homo (between 2.4 and 1.8 million years ago in Africa), they are now reconsidering some evolutionary factors that may have influenced the development of these human characteristics (1). New climate and fossil evidence discovered and analyzed by a team of scientists and researchers, suggested that our humansitic traits did not arise as a single developmental process (1) (2). Several key factors of evolutionary influence may have enabled humanoids to evolve in "earlier Australopithecus ancestors between 3 and 4 million years ago", while others could have emerged much later (1). The sceintists took an innovative approach by integrating paleoclimate data along with new fossils, archaeological remains, and biological studies of a diverse range of mammals and humans. Researchers also utilized climate and fossil data, reviewing "evidence from ancient stone tools, isotopes found in teeth and cut marks found on animal bones in East Africa" (1). The researchers developed a "new climate framework for East African human evolution" in which encompasses most of "the era from 2.5 million to 1.5 million years ago" and scientists think that this was a time of strong climate instability, with a significant shift of intensity in the annual wet and dry seasons (1). Based on the Earth 's astronomical cycles, this information implies that "multiple coexisting species of Homo" may have overlapped geographically, possibly having
It has long been thought by biologists that our physical features, such as our large brains, long legs, the ability to make and use tools, as well as our prolonged maturation periods had all evolved together in the beginning of the Homo lineage (1). This was a period of time when the African grasslands began to expand and the Earth 's climate cooled and became much drier (1) (2). Although scientists have recognized and known these traits to be specific to humans, which were thought to have originated in the genus Homo (between 2.4 and 1.8 million years ago in Africa), they are now reconsidering some evolutionary factors that may have influenced the development of these human characteristics (1). New climate and fossil evidence discovered and analyzed by a team of scientists and researchers, suggested that our humansitic traits did not arise as a single developmental process (1) (2). Several key factors of evolutionary influence may have enabled humanoids to evolve in "earlier Australopithecus ancestors between 3 and 4 million years ago", while others could have emerged much later (1). The sceintists took an innovative approach by integrating paleoclimate data along with new fossils, archaeological remains, and biological studies of a diverse range of mammals and humans. Researchers also utilized climate and fossil data, reviewing "evidence from ancient stone tools, isotopes found in teeth and cut marks found on animal bones in East Africa" (1). The researchers developed a "new climate framework for East African human evolution" in which encompasses most of "the era from 2.5 million to 1.5 million years ago" and scientists think that this was a time of strong climate instability, with a significant shift of intensity in the annual wet and dry seasons (1). Based on the Earth 's astronomical cycles, this information implies that "multiple coexisting species of Homo" may have overlapped geographically, possibly having
References: 1) Smithsonian. Timeline of Human Origins Revised: New synthesis of Research Links Changing Environment with Homo 's Evolutionary Adaptability. ScienceDaily. ScienceDaily, 3 July 2014. 2) Scally Aylwyn and Richard Durbin. Revising the Human Mutation Rate: Implications for Understanding Human Evolution. Nature Reviews Genetics 13.10 (2012): 745-53. Web