Communal Egg-laying In Reptiles And Amphibians: Evolutionary Patterns And Hypotheses

• Published in: The Quarterly review of biology Vol. 84; no. 3; pp. 229 - 252
• Main Authors: Doody, J.Sean, Freedberg, Steve, Keogh, J.Scott
• Format: Journal Article
• Language: English
• Published: United States The University of Chicago Press 01.09.2009; University of Chicago, acting through its Press
• Subjects: Adaptation, Psychological; Amphibians; Amphibians - classification; Amphibians - physiology; Animal nesting; Animals; Biodiversity; Biology; Bird nesting; Clutch Size; Eggs; Frogs; Game Theory; Genetic Speciation; Lacertilia; Lizards; Maternal Behavior; Mollusca; Nesting Behavior; Nesting sites; Oviposition; Predators; Reptiles; Reptiles & amphibians; Reptiles - classification; Reptiles - physiology; conspecific cueing; egg aggregations; oviposition site choice; evolutionary stable strategy; game theory
• ISSN: 0033-5770; 1539-7718
• DOI: 10.1086/605078

Communal egg-laying is widespread among animals, occurring in insects, mollusks, fish, amphibians, reptiles, and birds, just to name a few. While some benefits of communal egg-laying may be pervasive (e.g., it saves time and energy and may ensure the survival of mothers and their offspring), the remarkable diversity in the life histories of the animals that exhibit this behavior presents a great challenge to discovering any general explanation. Reptiles and amphibians offer ideal systems for investigating communal egg-laying because they generally lack parental carea simplification that brings nest site choice behavior into sharp focus. We exhaustively reviewed the published literature for data on communal egg-laying in reptiles and amphibians. Our analysis demonstrates that the behavior is much more common than previously recognized (occurring in 481 spp.), especially among lizards (N = 255 spp.), where the behavior has evolved multiple times. Our conceptual review strongly suggests that different forces may be driving the evolution and maintenance of communal egg-laying in different taxa. Using a game theory approach, we demonstrate how a stable equilibrium may occur between solitary and communal layers, thus allowing both strategies to co-exist in some populations, and we discuss factors that may influence these proportions. We conclude by outlining future research directions for determining the proximate and ultimate causes of communal egg-laying.