Format

Send to

Choose Destination
Laterality. 2014;19(5):591-601. doi: 10.1080/1357650X.2014.891606. Epub 2014 Feb 28.

When right differs from left: human limb directional asymmetry emerges during very early development.

Author information

1
a Department of Biology, Evolutionary Ecology Group , University of Antwerp , Antwerp , Belgium.

Abstract

The often observed directional asymmetry (DA) in human limb bones may have a genetic/developmental basis and/or could emerge from different mechanical loadings across sides due to handedness. Because behavioural lateralization in itself has a genetic basis, it has been suggested that DA in limbs could develop prenatally as a pre-adaptation to adult life. However, the presence of consistent differences in the size of left and right limb bones in early development is understudied. We study asymmetry in limb bones during early development (10-20 weeks of gestation) in a sample of 178 aborted foetuses. Statistically significant DA was found in several upper and lower limb bones, where the right-hand side was consistently larger than the left. We argue that this pattern is probably the consequence of developmental processes related to internal asymmetric positioning of organs.

KEYWORDS:

Directional asymmetry; Fluctuating asymmetry; Foetus; Handedness; Human

PMID:
24579655
DOI:
10.1080/1357650X.2014.891606
[Indexed for MEDLINE]

Supplemental Content

Loading ...
Support Center