Prey defences: mechanisms, evolution and ecology

一些被捕食的动物会躲避捕食者。有些人逃走了。还有一些人进行了反击。这项研究调查了导致猎物防御变化的进化和生态过程，以及猎物防御对动物的社会行为、父母照顾和生态模式的影响。我将解决为什么一些动物似乎无私地保护不是自己后代的个体免受捕食者攻击的问题。尽管无私行为的例子在动物界很常见，但我们并不认为这种行为是通过自然选择产生的。通过之前对骡鹿(一种看似无私的动物，保护幼鹿免受另一物种的伤害！)的研究，我排除了雌性保护非后代的可能性，因为它们把它们误认为是自己的后代，以及通常的观点，即雌性只帮助近亲，以便传递她们共同的基因。我现在将检验这样一种假设，即保护非后代是雌性保护自己幼崽的动机的溢出效应。对任何求救信号的僵化反应可能会确保雌性幼鹿在需要时保护自己，即使它有导致她保护许多其他动物的缺点。在另一项研究中，我将观察捕食者和猎物(郊狼、鹿和两种地松鼠)在草原景观中的自然相遇，以确定被捕食动物的行为和密度如何影响捕食者的狩猎成功，以及它决定猎杀一种猎物而不是另一种猎物的决定。因此，这项研究将促进我们对猎物防御的进化以及社会行为和父母照顾的相互交织的模式的理解。它还将深入了解个体猎物和捕食者的行为如何塑造猎物的生存模式。这项研究适用于自然保护。这将增加我们对土狼如何影响加拿大本土草原上的本地猎物物种的理解，这是一个支持着不成比例的濒危物种的栖息地。

SOME prey animals hide from predators. Some run away. Still others counterattack. This research investigates evolutionary and ecological processes leading to variation in prey defences, and the influence of prey defences on an animal's social behaviour, parental care and ecological patterns.   I will address the question of why some animals appear to altruistically defend individuals that are not their own offspring against predators. Even though examples of selfless behaviour are common in the animal world, we do not expect such behaviour to arise through natural selection. Through previous work with mule deer (a seemingly altruistic animal that defends fawns from another species!), I ruled out the possibility that females defend non-offspring because they mistake them for their own, and the common idea that females only help close relatives so as to pass on their shared genes. I will now test the hypothesis that the defence of non-offspring is a spillover of a female's motivation to defend her own fawn. A rigid response to any distress call may ensure a female defends her own fawn when it is in need, even if it has the drawback of leading her to defend many other animals.   In another line of research, I will observe natural encounters between predators and prey (coyotes, deer, and two species of ground squirrels) in a prairie landscape to determine how the behaviour and density of prey animals affect a predator's hunting success and its decision to hunt one species of prey rather than another.   This research will advance our understanding of the evolution of prey defences and intertwined patterns of social behaviour and parental care. It will also provide insight into the way the behaviour of individual prey and predators shapes survival patterns of prey. This research is applicable to conservation. It will increase our understanding of the way coyotes affect native prey species on Canada's native prairie grassland, a habitat supporting a disproportionate share of endangered species.