For sexual selection to act on a given sex, there must exist variation in the reproductive
success of that sex as a result of differential access to mates or fertilisations. The …

Long‐term studies have been the backbone of population ecology. The red grouse Lagopus
lagopus scoticus is one species that has contributed widely to this field since the 1950s. This …

Avian plumage has captivated scientists and the public alike for generations and has been a
fundamental study system for research into signal evolution. By contrast, relatively little …

Abstract Knowledge of the temporal variation in reproductive success and its key driving
factors is crucial in predicting animal population persistence. Few studies have examined …

In a reliable signalling system, individual quality is expected to mediate the costs associated
with ornamental displays, with relatively lower costs being paid by individuals of higher …

In many species, males invest both in weapons used in competitions for access to mates
and testes size to increase competitive chances for fertilizations. The expression of weapons …

The consequences of sex-specific selection for patterns of diversification remain poorly
known. Because male secondary sexual traits are typically costly to express, and both costs …

Sexual selection during range expansions has seldom been investigated, but it could be
important for speciation because expansions create peripatric populations and sexual …

Secondary sexual traits displayed by males and females may have evolved as a signal of
individual quality. However, both individual quality and investment on producing or …

The phenotype-linked fertility hypothesis (PLFH) proposes that both sexual ornaments and
sperm traits are phenotypically plastic and co-affected by environmental factors through …