Anniyden's page

I think there is some confusion here about r-selected and k-selected. These are relative terms, not absolute classificatory terms. Rats are k-selected compared to bees, but r-selected compared to elephants. Bees are k-selected compared to bacteria, but r-selected compared to dogs.

Yep, some of it is relative and there is gray area (heck some call it a continuum). In my experience, r and K is often used when describing community successional patterns - usually communities of relatively closely related taxa (eg fish community in a stream, trees in a forest, etc.). Originally, I believe r/k came from MacArthur and Wilson and their Theory of Island Biogeography. I recently read the paper where Simberloff and Wilson defaunated a series of mangrove islands (that's right kids - they nuked all life). The investigators then followed the trail of immigration and recolonization. I'd wager this is where Wilson came up with some of the r/K theory - from watching ants colonize mangrove islands.

In aquatics, I can definitely see some well defined r-strategists. Species that are extremely fecund, achieve sexual maturity quickly, possess a short life span, and are great dispersers. There are a lot of curveballs in the aquatic environment though that don't fit so neatly.

I'm trying to remember two terms that define sexually reproducing species: one term is for species that breed continually until their environment can't sustain them, then a bunch die off, then the process starts all over again. The other term is for species that only breed continually until their population reaches a healthy level, then breeding slows down so that their population plateaus out. Does that sound familiar?

I think what the OP may be trying to describe is the difference between iteroparous and semelparous organisms. Coined by Cole (1954). If this is what was meant by the OP, iteroparous organisms (EG humans) reproduce multiple times during their lifetime. Semelparous (EG pacific salmon) organisms reproduce once.

Otherwise, the reproductive scenario the OP describes does not occur quite as written. As has been shown by several classical ecological papers, organisms will continually reproduce until resources or conditions limit population size. Of course in nature there are a host of controls on populations - for example intraspecific competition, interspecific competition, predation, etc.