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Many young animals disperse from where they are born. A. There are a number of competing explanations of why animals disperse, but none of them is consistent with all the observed patterns of dispersal. B. The reason there is little inbreeding among lions is that young males are driven away from their female relatives by the adult males who forcibly take over a lion pride. C. Inbreeding significantly lowers the likelihood that offspring will survive, and so avoiding inbreeding is a significant benefit of dispersal. D. Since males of most species must establish a territory for mating, dispersing of the males makes it more likely that most males will be able to reproduce. E. There need to be significant benefits for a species to disperse because the requirements of dispersal involve energy costs and dangers for the dispersing individuals. F. In mammal species, young males often leave their family group while related females benefit from remaining in close association with each other and their birthplace.