It is thought that this general trend towards increased aridity had an important influence on the dispersal of early humans from their presumed original homeland. Rick Potts studied the pattern of climatic turnover in the fauna and the occurrence of archeological sites at Olorgesailie and another site in southern Kenya, and found that several large mammal species that had previously dominated the fauna of this region went extinct between aboutandyears ago, during a period of repeated environmental instability.
We have many social contacts and means of exchanging resources and information to help us survive in a constantly changing world.
Over the course of human evolution, hominins increased their abilities to cope with a number of different environments rather than specializing on a single environment.
Variability selection is meant to fill that gap in our understanding. These studies show Homo bucking a trend in which earlier peoples passively fed on the expanding grasslands, says deMenocal. Language makes it possible to convey complex ideas to others. Taken together these factors could ultimately threaten the whole future existence of the human race.
Dmanisi, Republic of Georgia, 1. Variability selection offers a different explanation.
We use resources from a vast variety of plants and animals and use many specialized tools. Encephalizationor the evolutionary enlargement of the brain relative to body size, was especially pronounced over the pastyears, coinciding with the period of strongest climate fluctuation worldwide.
Another version of this idea is that upright walking had the additional advantage of freeing the hands, which was advantageous for carrying items and making tools in the African savanna. If these processes acted the same way on hominins, Neanderthals and Denisovans may have arisen from early groups such as Homo heidelbergensis, when they became isolated in small, livable pockets of the frigid Northern Hemisphere.
Other tools were used to make clothing which would have been important for hominins in cold environments. I thought of variability selection when I became aware that the dominant savanna-grazing mammals of East Africa became extinct, replaced by more adaptable relatives, during periods of highly variable environment.
Image via Wikipedia Australopithecus family Stone Toolmaking: During wet periods, the layers contain light amalgamations of abundant fossilized plankton.
Sediments, stone artifacts, and animal faunal at the site of Olorgesailie span most of the past 1. Sediments, stone artifacts, and animal faunal at the site of Olorgesailie span most of the past 1.
When the ice melteda rise in humidity is thought to have led to the extinction of a number of large and dominant land mammals. The Neanderthals were able to adjust their behavior to fit the circumstances. Barbed points were used to spear fish.
Early evidence of the diversity of Homo erectus environments in Asia includes the following sites: How has variability selection been received by other anthropologists.
Neanderthals and modern humans had different ways of dealing with environmental fluctuation and the survival challenges it posed. Communication of ideas and circumstances via language would have made survival in a changing world much easier.
A relative of Theropithecus, the common baboon Papio, is still living. We have many social contacts and means of exchanging resources and information to help us survive in a constantly changing world. This site has grasslands surrounded by mountains with forests.
In the eastern Mediterranean, you find dark and light bands in deep-sea cores that indicate periods of very strong rainfall followed by drought in Africa.
There is now a good body of knowledge concerning climate changes that go back over the past 7 million years and there are a number of hypotheses regarding the way that these changes might have influenced the development of our species and its ecosystem.
I could see in these sorts of records that relative stability was followed by periods of instability. New Tools for Many Different Purposes Afteryears ago, hominins found new ways of coping with the environment by creating a variety of different tools. Barbed points were used to spear fish. Variability selection offers a different explanation.
They can show a certain capacity to adjust to a changing environment. This graph correlates changes in climate to changes in hominin brain size. Modern humans, Homo sapiens, had specialized tools to extract a variety of dietary resources.
The long-persisting baboon of East Africa was the large Theropithecus. But we humans have already proven our ability to survive in an amazing variety of conditions. How might we evolve in the future to face the new climate reality?
We asked professors of human origins, human evolution and the philosophy of biology, and speculative fiction author Margaret Atwood, to weigh on on our species’ future. Climate Effects on Human Evolution March 22,Anthropocene, Climate Science, Global, Health, Heat Stress, Life forms This article explores the hypothesis that key human adaptations evolved in response to environmental instability.
Did climate change shape human evolution? in Paleoclimate and Evolution with Emphasis on Human Origins, E.
Vrba, G. Denton, L. Burckle, Climate change and its effects on African ecosystems may have played a key role in human evolution. Share This Article: Copy. Climate and biological evolution have interacted throughout Earth's history and has resulted in many small and some major transformations in the planet's atmosphere and biota.
The role of climate in the origin and adaptations of humans related not only to the past, but potentially to the future. Climate Effects on Human Evolution The idea of variability selection, developed by Smithsonian researcher Dr. Rick Potts, seeks to explain how the dynamic surroundings of human ancestors shaped their ability – and ours – to adjust to a changing world.
janettravellmd.com: How is future climate change likely to affect human evolution? Potts: It is our survival challenge for the future.
I think it’s going to present some of the same kinds of challenges our ancestors faced: vastly changed landscapes, and ways of life that may no longer be able to thrive or even exist.Climate effects on human evolution