A new study on human brain evolution has challenged old ideas by revealing that modern humans, Neanderthals, and other relatives developed larger brains at a faster rate than earlier species. The research, published in the journal PNAS, found that brain size increased gradually within each ancient human species over millions of years.
The team assembled the largest-ever dataset of ancient human fossils spanning 7 million years and used advanced computational and statistical methods to account for gaps in the fossil record. Their findings suggest that brain size evolution is driven by gradual changes within individual species, rather than sudden leaps between species.
According to Professor Chris Venditti, co-author of the study, “This study completely changes our understanding of how human brains evolved. It was previously thought that brain size jumps dramatically between species.” The research highlights the importance of incremental growth in brain size and suggests that gradual adaptation is a more logical explanation for brain evolution.
The team also found that while larger-bodied species tend to have bigger brains, the variation within an individual species does not consistently correlate with body size. This suggests that brain size evolution across long evolutionary timescales is shaped by different factors than those observed within individual species.
Lead author Dr Thomas Puschel stated, “Big evolutionary changes don’t always need dramatic events. They can happen through small, gradual improvements over time.” The study’s findings provide new insights into the complex and nuanced process of brain evolution in humans.
Source: https://scitechdaily.com/big-brains-evolved-gradually-new-study-shakes-up-human-evolution-theory