The benefit of this strategy is that if resources are limited or unpredictable, you can still produce some young. Often, the eggs are fertilized and then dispersed. Such species are also generally not very invested in protecting or rearing these young. Such a species puts only a small investment of resources into each offspring, but produces many such low effort babies. R-selection: On one extreme are the species that are highly r-selected. Now imagine that you're an animal faced with the following choice: given limited resources, should you put them all into producing one or a few offspring, and protect them with great ferocity, or should you put a small amount of effort into a much larger number of offspring, and let them each take their chances? Should you measure out your reproductive effort over many seasons, or save it all up for a one-time mating frenzy as soon as you're able? These trade-offs relate to the r/K selection theory of life history strategies.Ī mouse produces a large litter. One way is to become the dominant animal in a pack, and to monopolize mating opportunities, but another way is to be submissive and sneaky, mating with others when the dominant animal is not around to stop you. As you might imagine, there are many ways to be reproductively successful. In the relay race of evolution, getting as many copies of your genes into the next generation as possible is the only goal. In evolutionary terms, it is of no consequence if an organism is a fine, fully mature, physical specimen, or the dominant member of the herd, or even that an individual produces a lot of young but none of them survive. Introduction: An organism's Darwinian fitness is calculated as the number of offspring it leaves behind that, themselves, survive to reproduce.

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