Sudden Climate Change Forced Evolution: Scientists

Early humans saw woodland shift to grassland
By Neal Colgrass,  Newser Staff
Posted Dec 26, 2012 2:30 PM CST
Updated Dec 29, 2012 7:00 PM CST
Sudden Climate Change Forced Evolution: Scientists
This undated handout photo shows the casts of two palates demonstrates the large size of the teeth of Paranthropus boisei (left), an early human relative that lived in East Africa.   (AP Photo/Melissa Lutz Blouin, University of Arkansas)

Early humans evolved in fits and starts due to rapid environmental changes—not gradually as scientists used to think, according to a new study. Analyzing lake sediments in northern Tanzania, scientists from Penn State and Rutgers University concluded that climate change altered the landscape back and forth from grassland to woodland five or six times over 200,000 years, the Telegraph reports. That would have changed food availability, diet, and means of acquiring food—which "can trigger evolutionary mechanisms," says Penn State professor Katherine Freeman.

"The result can be increased brain size and cognition, changes in locomotion and even social changes—how you interact with others in a group." Several factors may have triggered the climate changes about 2 million years ago, including changes in sea temperature and the Earth's movement around the sun. Any change in the amount of sunshine, for example, would have altered rain patterns that in turn affected plant patterns. "The research points to the importance of water in an arid landscape like Africa," says a graduate student on the project. The findings conflict with the "Great Drying," the view that Africa gradually dried out over 3 million years. (More climate change stories.)

Get the news faster.
Tap to install our app.
X
Install the Newser News app
in two easy steps:
1. Tap in your navigation bar.
2. Tap to Add to Home Screen.

X