[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Sauroparental care
> > I thought the bracket in this case was, then, ammonites and birds.
> Birds *are* ammonites.
Ah, _amniotes_ you are talking about! ~:-D
> > Then why do they scramble for the water? Predation must be
> > lower--locally, at least.
> They scramble for the water because that's where they can move and eat,
> I suspect.
In the long run, yes.
r is the reproductive rate, K is the carrying capacity. The Real True
Definition of r- and K-strategy, at least if you ask certain ecologists, is
that K-strategists have some inbuilt mechanisms or others which diminish
their reproductive rate when they approach the carrying capacity of the
ecosystem, resulting in the famous S-shaped growth curves, while
r-strategists lack such mechanisms and keep on growing logarithimically
until the population has surpassed the carrying capacity and collapses (only
to restart). By this definition, humans are probably r-strategists. There
are many mammals which e. g. fight so much when population density is high
that the stress diminishes their reproduction; this is apparently not the
case with us.
Well, there is a mechanism that is decreasing our reproductive rate,
so much so that the world population will have stopped growing before the
end of the century (I can dig out the ref); this is education*. But that's
* And not wealth or anything else, it seems.
Amartya Sen: Development as Freedom, Alfred A. Knopf 1999
Merry Xmas, everyone! :-)