Parental care has been widely studied in birds and mammals, but variation in space use in family groups has received less attention, despite its potential importance for both survival and subsequent dispersal of offspring. In this study, we evaluate factors affecting postfledging family space...

Many animals possess camouflage markings that reduce the risk of detection by visually hunting predators. A key aspect of camouflage involves mimicking the background against which the animal is viewed. However, most animals experience a wide variety of backgrounds and cannot change their...

Parental care is often beneficial for the young but costly for the caregiving parent. Because both parents benefit from care via the offspring, whereas they pay the costs individually, a conflict is expected about how much care each parent should provide. How do parents settle this conflict? We...

How and why do the mating opportunities of males and females differ in natural population of animals? Previously we showed that females have higher mating opportunities than males in the Kentish plover Charadrius alexandrinus. Both parents incubate the eggs, and males provide more brood care...

Two, logically distinct but sometimes compatible, mechanisms of camouflage are background-matching and disruptive coloration. In the former, an animal's coloration comprises a random sample of the background, and so target--background discrimination is impeded. In the latter, object or feature...

Ultraviolet (UV) vision is well documented for many species of vertebrates. UV cues are known to be used in foraging, navigation and in mate choice. We conducted a series of behavioral experiments to investigate the role of UV perception in mate choice in both female and male guppies (Poecilia...

Although the study of environmental change has long been of academic interest, the effects of change have become a much more pressing concern in the past few decades due to the often disruptive effect of human expansion and innovation. Researchers from many fields contribute to understanding our...

A dichotomy in female extrapair copulation (EPC) behavior, with some females seeking EPC and others not, is inferred if the observed distribution of extrapair young (EPY) over broods differs from a random process on the level of individual offspring (binomial, hypergeometrical, or Poisson). A...

Ultraviolet (UV) signals are suggested to be sexually selected in a wide range of taxa. Most research, however, has focused on the role of UV signals in mate choice, whereas possible functions in intraspecific competition remain largely untested. Studies on other colors indicate that ornaments...

Avian eggs contain maternal androgens that may adjust offspring development to environmental conditions. We review evidence and functional explanations for the relationship between androgen concentrations in avian eggs and male attractiveness. Experimental studies in captive birds show generally...