Human Brain Evolution Is Different From Tooth Evolution, Study Reveals

Evolutionary biologists have long believed that the evolution of human brain and other body parts, especially the teeth size, occurred simultaneously. The theory of co-evolution was on the verge of being accepted as a dogma in evolutionary biology. However, in the light of the new evidence, it seems that human brain and teeth did not have the same evolutionary history.

Evolution of human brain and teeth occurred under the influence of various ecological factors and behavioral patterns. A team of researchers from the Center for the Advanced Study of Human Paleobiology (CASHP), under George Washington University, found that the evolution of human brain size varied with species type under "Homo" genus, whereas evolution of teeth followed a similar pattern, India Today reported.

The researchers did a comparative analysis of evolutionary patterns of various "Homo" species by studying developmental characters of members of different branches of the human evolutionary tree.

Aida Gomez-Robles at CASHP said that, "The findings of the study indicate that simple causal relationships between the evolution of brain size, tool use and tooth size are unlikely to hold true" when the "scenarios of hominin evolution and the extended time periods during which evolution occurred" are taken into consideration.

The researchers analyzed eight different hominin species and pointed out the fast-evolving species by studying the differences and similarities between the different groups. The results obtained suggest visible differences between evolutionary patterns, which do not correspond to the classical theory of co-evolution of human brain and tooth, i4U News reported.

Experts say that if the earlier theory would have been true, then there must be synchrony between the patterns of evolution, which was not observed in the study.

Bernard Wood, Professor at George Washington University, said, "Once something becomes conventional wisdom, in no time at all it becomes dogma." He also stated that, "The co-evolution of brains and teeth was on a fast-track to dogma status, but we caught it in the nick of time."

The findings indicate that people's present perceptions regrading evolution of human brain or other body features may not be true in all cases, and the future of evolutionary biology may hold some big surprises.