Medical Sciences Commons^™

The Cost Of Arm Autotomy In The Starfish Stichaster-Striatus, John M. Lawrence, A. Larrain

Integrative Biology Faculty and Staff Publications

Arm autotomy in asteroids, as tail autotomy in vertebrates, typically occurs when the animal is attacked and appears to facilitate escape. One assumes autotomy has a cost, but it rarely has been demonstrated in the field in vertebrates and never demonstrated in asteroids. The concentration of lipid was 40 % less and the amount of kilojoules 85 % less in the pyloric caeca of the asteroid Stichaster striatus Muller & Troschel (Echinodermata: Asteroidea) with autotomized arms than in those of individuals with intact arms collected in the field. as the pyloric caeca are used as nutrient reserves, individuals with autotomized …