title: Conspicuous and aposematic spines in the animal kingdom.
abstract: Spines serve as a common physical defence mechanism in both the plant and animal kingdoms. Here we argue that as in plants, defensive animal spines are often conspicuous (shape and colour) and should be considered aposematic. Conspicuous spines may evolve as signals or serve as a cue for potential predators. Spine conspicuousness in animals has evolved independently across and within phyla occupying aquatic and terrestrial ecosystems, indicating that this convergent phenomenon is highly adaptive. Still, many spines are cryptic, suggesting that conspicuity is not simply constrained by developmental factors such as differences in the chemical composition of the integument. Aposematism does not preclude the signalling role of conspicuous spines in the sexual arena.
authors.affiliation: Department of Environmental and Evolutionary Biology, University of Haifa, Haifa 31905, Israel. minbar@research.haifa.ac.il
authors.forename: Moshe
authors.initials: M
authors.lastname: Inbar
authors.forename: Simcha
authors.initials: S
authors.lastname: Lev-Yadun
mesh_terms: D000818:Animals; D003445:Crustacea / Q000033:anatomy & histology / Q000502:physiology; D004777:Environment; D005399:Fishes / Q000033:anatomy & histology / Q000502:physiology; D006110:Grasshoppers / Q000033:anatomy & histology / Q000502:physiology; D008974:Mollusca / Q000033:anatomy & histology / Q000502:physiology; D010858:Pigmentation; D046328:Porcupines / Q000033:anatomy & histology / Q000502:physiology