Climate: Its effect on the development of the human body and brain

Climate change may be the biggest concern of the modern man. Yet a new study has found that the climate has already changed the size of the human body and brain over a million years. Researchers from the University of Cambridge say that the average size of the human body has fluctuated over the last one million years due to changes in temperature. Colder climates lead to the creation of larger bodies while warmer climates lead to smaller bodies. The size of the brain also changed dramatically, but did not evolve in parallel with the size of the body, according to the findings.

Larger bodies

The authors of the study from the Universities of Cambridge and Timben (Germany), collected measurements of body and brain size from more than 300 fossils of the Homo species. Combining the data with the reconstruction of the climates in different parts of the world over the last one million years, they identified the specific climate that each fossil endured when it was a living human being. Their findings reveal that the average human body size has changed significantly. In particular, the researchers noted that larger bodies can function better in lower temperatures, as less heat is lost from a body when its mass is larger related to its surface. Our species, Homo sapiens, appeared about 300,000 years ago in Africa. The researchers explain that a defining feature of the evolution of our species is a tendency to increase the size of the body and the brain. Compared to previous species, such as Homo habilis, modern humans are 50 percent heavier and our brains are three times larger.

And the brain?

The team also looked at the effect of environmental factors on brain size in the Homo species, but found that the link between the two appears to be weak. The size of the brain tends to be larger when Homo lived in habitats with less vegetation, such as open steppes and meadows, but also in more ecologically stable areas. Combined with archaeological data, the results suggest that people living in these habitats hunted large animals for food. This was a complex task that could have led to the evolution of larger brains. According to the study, non-environmental factors were more important for brain growth than climate.

Will technology affect the human brain?

The researchers say there is significant evidence that the size of the human body and brain continues to evolve as the human body continues to adapt to different temperatures. However, the size of the brain in our species seems to be “shrinking” starting about 12,000 years ago. Scientists claim that our increasing dependence on technology can cause the brain to shrink even more in the future. Giota Florou Source: studyfinds.org Recent Articles