Socially monogamous birds have provided a major focus of research in the field of sexual
selection, providing insight into the evolution of ornaments, sexual dimorphism and sex …

Why do some animals mate with one partner rather than many? Here, I investigate factors
related to (i) spatial constraints (habitat limitation, mate availability),(ii) time constraints …

Some nonhuman animals form adaptive long-term cooperative relationships with nonkin that
seem analogous in form and function to human friendship [1–4]. However, it remains unclear …

Background A central part of an animal's environment is its interactions with conspecifics.
There has been growing interest in the potential to capture these interactions in the form of a …

Male reproductive success depends on the competitive ability of sperm to fertilize the ova,
which should lead to strong selection on sperm characteristics. This raises the question of …

Avian hatching failure is a widespread phenomenon, affecting around 10% of all eggs that
are laid and not lost to predation, damage, or desertion. Our understanding of hatching …

Noise pollution is expanding at an unprecedented rate and is increasingly associated with
impaired reproduction and development across taxa. However, whether noise sound waves …

Behavioral similarity between partners is likely to promote within-pair compatibility and to
result in better reproductive success. Therefore, individuals are expected to choose a …

Learning is ubiquitous in animals: individuals can use their experience to fine-tune
behaviour and thus to better adapt to the environment during their lifetime. Observations …

There are two unresolved puzzles in the literature examining how people evaluate mates
(ie, prospective or current romantic/sexual partners). First, compatibility is theoretically …