Editing Behavioral ecology (section)

====Monogamy====
Monogamy is the mating system in 90% of birds, possibly because each male and female has a greater number of offspring if they share in raising a brood.<ref>Lack, D. (1968) Ecological Adaptations for Breeding in Birds. Methuen, London.</ref> In obligate monogamy, males feed females on the nest, or share in incubation and chick-feeding. In some species, males and females form lifelong pair bonds. Monogamy may also arise from limited opportunities for polygamy, due to strong competition among males for mates, females suffering from loss of male help, and female–female aggression.<ref name="Davies et al., (2012) pp. 266">Davies, N. B., Krebs, J. R and West, S. A., (2012). ''An Introduction to Behavioral Ecology.'' West Sussex, UK: Wiley-Blackwell. p. 266. {{ISBN|978-1-4051-1416-5}}.</ref>