@article{
author = "Golubovic, Ana and Tomovic, Ljiljana and Ivanovic, Ana",
year = "2015",
abstract = "Armoured animals can easily lose their balance and fall on their back.
When overturned, they can be exposed to suboptimal environment
conditions, starvation or predation, thus, self-righting has a vital
importance. Chelonians' stiff shells prevent torsion of the torso, thus
influence of the dorsum shape on self-righting can be significant. We
explored the relationship between duration of active self-righting
attempts and shell geometry in Hermann's tortoises. We used geometric
morphometrics and shell shape indices (R index, sphericity and flatness
indices) to explore this effect. Our results showed a negative
relationship between size and righting performance in both females and
males. Enlarged females' body, and thus reduced agility, could be
favoured by fecundity selection. On the other hand, the body size of
males is probably affected by sexual selection. Additionally, enlarged
flared rear marginal scutes in males negatively affect self-righting.
This part of males' shells could be shaped by the trade-off between
self-righting and stability during courtship and mating. However, the
relationship between carapace shape and righting performance is not
straightforward, as different results were obtained when various shape
indices were applied in the analyses. The indices imply that greater
curvature of the carapace shape facilitates self-righting in Hermann's
tortoises. Comparison of available literature data and results of this
study imply that shell shape across the Testudo genus, except for T.
marginata, largely overlaps with shell shape of T. hermanni. Thus, a
similar effect of shell shape on self-righting performance could be
expected for most of Testudo species. (C) 2014 Elsevier GmbH. All rights
reserved.",
journal = "Zoologischer Anzeiger",
title = "Geometry of self righting: the case of Hermann's tortoises",
volume = "254",
doi = "10.1016/j.jcz.2014.12.003",
pages = "99-105"
}
