TY - JOUR
T1 - Paternal genotype influences incubation period, offspring size, and offspring shape in an oviparous reptile
AU - Olsson, Mats
AU - Gullberg, Annica
AU - Shine, Richard
AU - Madsen, Thomas
AU - Tegelström, Håkan
PY - 1996/6
Y1 - 1996/6
N2 - Theoretical models for the evolution of life-history traits assume a genetic basis for a significant proportion of the phenotypic variance observed in characteristics such as hatching date and offspring size. However, recent experimental work has shown that much of the phenotypic variance in hatchling reptiles is induced by nongenetic factors, such as material nutrition and thermoregulation, and the physical conditions experienced during embryogenesis. Thus, there is no unambiguous evidence for strictly genetic (intraspecific) influences on the phenotypes of hatchling reptiles. We report results from a technique that uses a genetic marker trait and DNA fingerprinting to determine paternity of offspring from multiply sired clutches of European sand lizards, Lacerta agilis. By focusing on paternal rather than maternal effects, we show that hatchling genotypes exert a direct influence on the duration of incubation, the size (mass, snout-vent length) and shape (relative tail length) of the hatchling, and subsequent growth rates of the lizard during the first 3 mo of life. Embryos with genes that code for a few days' delay in hatching are thereby larger when they hatch, having undergone further differentiation (and hence, have changed in bodily proportions), and are able to grow faster after hatching. Our data thus provide empirical support for a crucial but rarely tested assumption of life-history theory, and illuminate some of the proximate mechanisms that produce intraspecific variation in offspring phenotypes.
AB - Theoretical models for the evolution of life-history traits assume a genetic basis for a significant proportion of the phenotypic variance observed in characteristics such as hatching date and offspring size. However, recent experimental work has shown that much of the phenotypic variance in hatchling reptiles is induced by nongenetic factors, such as material nutrition and thermoregulation, and the physical conditions experienced during embryogenesis. Thus, there is no unambiguous evidence for strictly genetic (intraspecific) influences on the phenotypes of hatchling reptiles. We report results from a technique that uses a genetic marker trait and DNA fingerprinting to determine paternity of offspring from multiply sired clutches of European sand lizards, Lacerta agilis. By focusing on paternal rather than maternal effects, we show that hatchling genotypes exert a direct influence on the duration of incubation, the size (mass, snout-vent length) and shape (relative tail length) of the hatchling, and subsequent growth rates of the lizard during the first 3 mo of life. Embryos with genes that code for a few days' delay in hatching are thereby larger when they hatch, having undergone further differentiation (and hence, have changed in bodily proportions), and are able to grow faster after hatching. Our data thus provide empirical support for a crucial but rarely tested assumption of life-history theory, and illuminate some of the proximate mechanisms that produce intraspecific variation in offspring phenotypes.
KW - incubation period
KW - Lacerta agilis
KW - multiple paternity
KW - offspring size and shape
KW - paternal genes
UR - http://www.scopus.com/inward/record.url?scp=0029661714&partnerID=8YFLogxK
U2 - 10.1111/j.1558-5646.1996.tb02372.x
DO - 10.1111/j.1558-5646.1996.tb02372.x
M3 - Article
C2 - 28565274
AN - SCOPUS:0029661714
SN - 0014-3820
VL - 50
SP - 1328
EP - 1333
JO - Evolution
JF - Evolution
IS - 3
ER -