Southall E J, Sims D W
Marine Biological Association, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK.
Proc Biol Sci. 2003 Aug 7;270 Suppl 1(Suppl 1):S47-9. doi: 10.1098/rsbl.2003.0006.
Dermal denticles are unique tooth-like structures embedded in the skin of sharks and rays that protect them from predators and ectoparasites, reduce mechanical abrasion and possibly minimize swimming-induced drag. Here, we show that juvenile lesser spotted dogfish (Scyliorhinus canicula) also use this body armour to anchor food items near their tail so that bite-sized pieces can be torn away by rapid jaw and head movements. This scale-rasp behaviour is novel among fishes and suggests a new role for skin in the feeding ecology of sharks. Scale rasping may be important ecologically because it could function to increase the dietary breadth and growth potential of juveniles.
皮齿是鲨鱼和鳐鱼皮肤中独特的齿状结构，可保护它们免受捕食者和体外寄生虫的侵害，减少机械磨损，并可能使游泳引起的阻力降至最低。在这里，我们表明，幼年的小斑点猫鲨（Scyliorhinus canicula）也利用这种“身体护甲”将食物固定在靠近尾巴的位置，以便通过快速的颌部和头部运动撕下大小合适的碎片。这种刮擦鳞片的行为在鱼类中是新颖的，表明皮肤在鲨鱼的摄食生态中具有新的作用。刮擦鳞片在生态上可能很重要，因为它可以增加幼鲨的食物种类和生长潜力。
