This “craniofacial dexterity” makes the bites of the cichlids stronger when done from the favored side, giving them an advantage in their chosen hunting strategy.

The researchers from use University, led by Thomas Stewart and R. Craig Albertson have also discovered the gene locus responsible for these morphologic divergences, they report in the journal BMC Biology.

While nature often favors either radial or bilateral symmetry, it does not hesitate before asymmetrical solutions. For example, the human heart is usually slightly left, and structures of the left and right parts of the brain are clearly different.

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