How Asymmetries Evolved: Hearts, Brains, and Molecules

Symmetry

MichaelC. Corballis¹ 

[1] School of Psychology, University of Auckland, Auckland 1142, New Zealand;

关键词: bilateria;    cerebral asymmetry;    handedness;    language;    molecular asymmetry;    situs;   

DOI  :  10.3390/sym13060914

来源: DOAJ

【 摘 要 】

Humans belong to the vast clade of species known as the bilateria, with a bilaterally symmetrical body plan. Over the course of evolution, exceptions to symmetry have arisen. Among chordates, the internal organs have been arranged asymmetrically in order to create more efficient functioning and packaging. The brain has also assumed asymmetries, although these generally trade off against the pressure toward symmetry, itself a reflection of the symmetry of limbs and sense organs. In humans, at least, brain asymmetries occur in independent networks, including those involved in language and manual manipulation biased to the left hemisphere, and emotion and face perception biased to the right. Similar asymmetries occur in other species, notably the great apes. A number of asymmetries are correlated with conditions such as dyslexia, autism, and schizophrenia, and have largely independent genetic associations. The origin of asymmetry itself, though, appears to be unitary, and in the case of the internal organs, at least, may depend ultimately on asymmetry at the molecular level.

【 授权许可】

Unknown