Fleming Patricia A, Muller Davina, Bateman Philip W
School of Veterinary and Biomedical Sciences, Murdoch University, Murdoch WA 6150, Australia.
Biol Rev Camb Philos Soc. 2007 Aug;82(3):481-510. doi: 10.1111/j.1469-185X.2007.00020.x.
Autotomy is defined herein as the shedding of a body part, where (1) the loss of the body part is defensive (autotomy helps prevent the whole animal from being compromised and is in response to external stimuli); (2) shearing occurs by an intrinsic mechanism along a breakage plane (there has been selection for certain body parts to be pulled off easily); and (3) the loss is controlled - the animal moves away from the trapped limb, the loss is under some form of central control (neural or hormonal), or the body part is detached quickly. Autotomy (under this defensive definition) has evolved independently for a diverse array of body parts in many taxa; we have summarised available information for over 200 invertebrate species. The advantages of autotomy include escape from entrapment, an effective form of attack, expulsion of an infected body part or in limiting wounding. We discuss how the incidence of autotomy may therefore be correlated with various traits such as limb function, sex differences, other defence mechanisms, habitat disturbance, and sociality. There are also costs associated with autotomy. Short-term costs include loss of a specialised appendage or organ, reduced speed and stability, or even death. Long-term costs include compromised foraging and feeding (often leading to reduced growth), altered anti-predator, competitive or reproductive behaviour, and even defective development. Regenerating lost appendages may also incur significant costs for the individual. We examine the costs and benefits of autotomy, and discuss the evolutionary selective pressures that contribute to the prevalence and effectiveness of autotomy in invertebrates.
自残在此被定义为身体部位的脱落，其中：（1）身体部位的丢失具有防御性（自残有助于防止整个动物受到伤害，并是对外部刺激的反应）；（2）沿着断裂平面通过内在机制发生剪切（某些身体部位已被选择以便容易被扯掉）；并且（3）丢失是可控的——动物远离被困肢体，丢失受到某种形式的中枢控制（神经或激素），或者身体部位迅速分离。自残（在这种防御性定义下）在许多分类群中针对各种各样的身体部位独立进化；我们总结了200多种无脊椎动物物种的现有信息。自残的优点包括摆脱被困、一种有效的攻击形式、排出受感染的身体部位或限制受伤。我们讨论了自残的发生率因此可能如何与各种特征相关，如肢体功能、性别差异、其他防御机制、栖息地干扰和社会性。自残也有成本。短期成本包括失去一个专门的附属物或器官、速度和稳定性降低，甚至死亡。长期成本包括觅食和进食能力受损（通常导致生长减缓）、反捕食行为、竞争行为或繁殖行为改变，甚至发育缺陷。再生丢失的附属物对个体来说也可能产生重大成本。我们研究了自残的成本和收益，并讨论了导致自残在无脊椎动物中普遍存在和有效的进化选择压力。
