KIN SELECTION & SYNCHRONISED REPRODUCTION

=Kin-selection= Organisms will tend to give the most care to those offspring that are most closely related to them. Some will exhibit strategies that '''favour the reproductive success of their relatives''', even at a cost to their own survival and/or reproduction. This process of favouring the reproductive success of relatives is a type of selection pressure known as kin selection and will result in changes in the gene frequency across generations. [image:http://i.imgur.com/M59cwDVt.png] Young Florida scrub-jays (picture left) will stay with their parents a year or two as helpers at the nest before leaving to mate themselves. In humans, post-reproductive females (grandmothers) are often involved in caring for their grandchildren. Social insect colonies, such as ants, are also a good example of kin-selection. Sterile females act as workers to assist a single queen (their mother) in the production of additional offspring. ==Synchronised Reproduction== [image:http://i.imgur.com/ujlL8Hvb.png] Many organisms will reproduce at the same time. This can be coupled to an environmental cue and in some species ensures that males and female produce eggs / sperm at the same time (synchronised spawning). It also allows for co-operative care of the resulting offspring. For instance, lionesses litter at the same time, nursing and caring for cubs communally.