The Evolution of Seasonal Delayed Implantation

摘要: Seasonal delayed implantation has been described in 47 mammalian species ten families, and evolved independently at least 17 times. After reviewing earlier explanations for the phenomenon I present a hypothesis to explain evolution of seasonal delay. have assumed that females can increase their fitness by chossing mates. Consequently, mating should take place during time year when possibilities female choice or male competition are greates. Time birth is determined ecological factors promoting survivals young, thereby setting certain constraints on scheduling season. In situations, however, be increased earlier; delay will fitness, evolve. The applied all cases implantation.