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( Behavioral ecology)
Behavioral ecology is the study of the ecological and evolutionary basis for animal behavior, and the roles of behavior in enabling an animal to adapt to its environment (both intrinsic and extrinsic). Behavioral ecology emerged from ethology after Niko Tinbergen (a seminal figure in the study of animal behavior), outlined the four causes of behavior. The two causes that contribute to ultimate causation are phylogenetic constraints that contribute to the development of behavior and the second is adaptive significance. Phylogenetic constraints are generally factors that might stop certain lineages developing certain behavioral or morphological traits. Hence, it is no coincidence that generally birds are able to fly and mammals cannot. The evolutionary history of these lineages have made it profitable for birds to fly and for mammalian feet to remain planted on the ground. Adaptive significance is akin to asking what a trait is good for in an evolutionary context. Therefore, the adaptive significance of flight in birds might have enabled avian ancestors to escape from predators. However, it is not sufficient to apply these explanations where they seem convenient. These have been labeled Just So Stories by some biologists after Rudyard Kipling's tales for children about how animals came to be the way they are. To be rigorous, one must suppose a hypothesis and then test it scientifically. Hence, for avian flight, one can suppose that when birds are not at risk of being eaten, they might lose the ability to fly. Proximate causation is also divided into two factors which are ontogenetic and mechanistic. Ontogenetic factors are the entire sum of experience throughout the lifetime of an individual from embryo to death. Hence, factors included are learning the genetic factors giving rise to behavior in individuals. Mechanistic factors, as the name implies, are the processes of the body that give rise to behavior such as the effects of hormones on behavior and neuronal basis of behavior. Behavioral ecology, along with other areas of evolutionary biology, has incorporated a number of techniques which have been borrowed from optimization theory. Optimization is a concept that stipulates strategies that offer the highest return to an animal given all the different factors and constraints facing the animal. One of the simplest ways to arrive at an optimal solution is to do a cost/benefit analysis. By considering the advantages of a behavior and the costs of a behavior, it can be seen that if the costs outweigh the benefits then a behavior will not evolve and vice versa. This is also where the concept of the trade-off becomes important. This is because it rarely pays an animal to invest maximally in any one behavior. For example, the amount of time an ectothermic animal such as a lizard spends foraging is constrained by its body temperature. The digestive efficiency of the lizard also increases with increases in body temperature. Lizards increase their body temperature by basking in the sun. However, the time spent basking decreases the amount of time available for foraging. Basking also increases the risk of being discovered by a predator. Therefore, the optimal basking time is the outcome of the time necessary to sufficiently warm itself to carry out its activities such as foraging. This example shows how foraging is constrained by the need to bask (intrinsic constraint) and predation pressure (extrinsic constraint).
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Behavioral ecology Subcategories
Behavioral ecology Articles
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