title: Determinants of anti-predator tactics in hatchling grass snakes (Natrix natrix).
abstract: Many organisms exhibit diverse anti-predator tactics, influenced by genetics and prior experience. In ectothermic taxa, offspring phenotypes are often sensitive to developmental temperatures. If the effectiveness of alternative anti-predator responses depends on thermally sensitive traits, then the temperatures experienced during embryonic life should also affect how offspring respond to an approaching predator. We incubated 16 clutches of Swedish grass snakes (Natrix natrix) at a range of developmental temperatures, and scored body size, colour pattern, locomotor performance and anti-predator responses of 213 hatchlings from those clutches. A hatchling snake's size and locomotor abilities were affected by its clutch of origin, its developmental temperature, and by an interaction between these two factors. Anti-predator tactics were strongly linked to locomotor ability, such that slower snakes tended to rely upon aggressive displays rather than flight. Incubation temperatures that generated slow (and thus aggressive) snakes also modified the colour of the snake's nuchal spot. Temperatures in the low to medium range generated mostly cream, white and orange spots, whereas medium to high temperatures generated more yellow spots. Incubation effects, and gene X environment interactions, thus may generate complex correlations between morphology, locomotor ability, and anti-predator tactics.
authors.affiliation: Biological, Earth and Environmental Sciences D26, University of New South Wales, NSW 2052, Australia. Electronic address: m.hagman@unsw.edu.au.
authors.forename: Mattias
authors.initials: M
authors.lastname: Hagman
authors.affiliation: Department of Zoology, Stockholm University, 106 91 Stockholm, Sweden.
authors.forename: Kristin
authors.initials: K
authors.lastname: Löwenborg
authors.affiliation: Biological Sciences A08, University of Sydney, NSW 2006, Australia.
authors.forename: Richard
authors.initials: R
authors.lastname: Shine
mesh_terms: D000374:Aggression / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D017812:Colubridae / Q000502:physiology*; D004625:Embryo, Nonmammalian; D005260:Female; D008297:Male; D008425:Maternal Behavior; D009043:Motor Activity; D010858:Pigmentation; D011235:Predatory Behavior; D013696:Temperature
keywords: Developmental plasticity; Incubation effects; Maternal effects; Trait correlations