Family Dynamics in Killer Whales: Consequences for Behaviour and Life History

In social species related individuals (kin) often live together in close knit family groups and individuals can influence the survival and reproductive success of their relatives both by their behaviour and reproductive decisions. Such interactions between kin are a strong evolutionary force, with individuals gaining indirect benefits (through the genes they share with relatives) by increasing the survival and reproductive success of their kin. The opportunity for evolution to be shaped by kin selection is dependent on how and when related individuals interact. For many natural populations patterns of interactions among kin (kinship networks) are likely to be variable both over time and among individuals. This variation is likely to have a profound impact on the evolution of both behaviour and life history. Currently however, for many wild animal populations, very little is known about variation in kinship networks (both among individuals and within individuals over time) and their evolutionary consequences.

This project will examine variation in kinship networks both among individuals and within individuals over time and determine the consequences of this variation for the evolution of both behaviour and life history. The project will focus on killer whales that live in the coastal waters of Washington State and British Columbia. The killer whales in this region have been studied for over four decades by the Center for Whale research who have collected detailed data on hundreds of known individuals documenting their birth, death, and patterns of social behaviour. This project will use both historical data and new data collected over the duration of the project to construct social networks to quantify variation in kinship networks and determine how an individual's social environment changes over time. Survival analysis will be used to examine the link between social structure and survival. Depending on the interests and background of the student there may also be the opportunity to examine these questions theoretically using computer simulations. The outputs of this work will establish the consequences of kin structure for patterns of survival and reproduction in killer whales and determine how these effects differ among individuals and change over time.