G. Sorci et J. Clobert, ENVIRONMENTAL MATERNAL EFFECTS ON LOCOMOTOR PERFORMANCE IN THE COMMONLIZARD (LACERTA-VIVIPARA), Evolutionary ecology, 11(5), 1997, pp. 531-541
Environmental (i.e. non-genetic) maternal effects have the potential t
o associate the environmental conditions faced by mothers during gesta
tion or before egg laying with the phenotype of their offspring. For t
his reason, maternal effects may play a major role in determining offs
pring phenotype independently of the genotype of the individuals, and
can thus be considered a mechanistic basis of phenotypic plasticity. D
espite the ecological and evolutionary implications of environmental m
aternal effects, few studies have experimentally investigated this phe
nomenon in reptiles. Here we report the results of an experimental lab
oratory study on the effects of maternal feeding rate and density on o
ffspring locomotor performance in the common lizard (Lacerta vivipara)
. Lacerta vivipara is a viviparous lizard, and viviparity enhances the
probability of a maternal influence on offspring phenotype. We focuse
d on a particular phenotypic trait, maximal sprint running speed, beca
use this trait is thought to be selectively important in squamates. Sp
rint speed was a repeatable trait. and it varied significantly among f
amilies. Maternal feeding rate significantly affected sprint speed, wh
ereas density had no effect on this trait. The effect of maternal feed
ing rate differed according to the sex of the offspring and their body
size, resulting in significant two-way and three-way interactions amo
ng these factors. In other words, the maternal feeding rate changed th
e shape of the allometric relationship between speed and size, but dif
ferently for males and females. The complexity of such effects makes i
t extremely difficult to offer an adaptive interpretation, but emphasi
zes the role played by the environment in shaping phenotypes among gen
erations.