The effects of sex hormones on immune function have received much attention, especially
following the proposal of the immunocompetence handicap hypothesis. Many studies, both …

Reptiles are ectothermic amniotes, providing the key link between ectothermic anamniotic
fishes and amphibians, and endothermic amniotic birds and mammals. A greater …

Summary 1 Phenotypic plasticity may allow an organism to respond to temporally variable
opportunities for growth and risks of mortality. However, life‐history theory assumes that …

A central tenet of life‐history theory is that investment in reproduction compromises survival.
However, the underlying physiological mechanisms that link reproduction to survival are …

Pheromones are chemicals involved in intraspecific communication in many animals.
Reptiles probably rely more on their chemical senses than any other vertebrate class and …

Pheromones have been defined, based on entomological studies, as chemicals or
semiochemicals produced by one individual that effect a change in the physiology …

The evolution and ecology of consistent behavioural variation, or personality, is currently the
focus of much attention in natural populations. Associations between personality traits and …

This article is part of a Special Issue “Chemosignals and Reproduction”. Many lizards have
diverse glands that produce chemosignals used in intraspecific communication and that can …

1. Testosterone (T) co-ordinates the seasonal and sex-specific expression of numerous
physiological, behavioural and morphological traits that contribute to male reproductive …

Highlights•We review hypotheses for honest signalling and physiological/social cost
models.•We review key empirical studies to determine support for these hypotheses.•Social …