Reproductive Strategies in Relation to Maternal Phenotype in a Model Lizard (Salvator merianae)

Abstract

Reproductive strategies can be characterized according to how often and when females reproduce, how much they invest, and how reproductive investment is distributed. Plasticity can lead to changes in reproductive strategies associated with some age/size classes. Therefore, elucidating associations between maternal morphological traits and reproductive investment over the lifespan will contribute to the understanding of the meaning of female phenotypic variability. Lizards have been an interesting model group for studying reproductive strategies from an ecological and evolutionary perspective in recent decades due to their life-history diversity. The aim of this work was to elucidate variations in the reproductive investment of females according to their multivariate morphology in order to understand if the expression of phenotypic variability is accompanied by variability in reproductive strategies of females in Salvator merianae. We found an annual-biennial pattern of reproduction dependent on female phenotype. Fat storage and follicle development were plastic traits that varied with female body size. Moreover, multiple phenotypic traits other than body length were signs of the reproductive value of a female; tail and abdominal perimeter were related to potential clutch mass and clutch size, respectively. Oviductal traits varied among females of different body length and were determinant of clutch size. Mass of total clutch and individual eggs varied independently of the number of offspring and were inversely related to interlimb length. Therefore, the variability found in the different reproductive traits associated to morphological traits indicates that variability in reproductive strategies is related to multivariate maternal phenotype, although the species does not exhibit discrete phenotypic differences.