Re: Extinction and Loss of Habitat
>Am I missing something? Did the big dinosaurs die off because of loss of
>habitat? Most species have died out because they are failures of one sort
>or another or are not able to keep up with a changeable world. This is
>basic Darwin and modern permutations thereof. I think I am safe in saying
>this is science.
As a matter of fact, more than likely the majority of the "big dinosaurs"
died off due to a sudden an extreme loss of habitat - at the end of the
Cretaceous period, due to the earth's colliding with a large asteroid
resulting in loss of sunlight, global warming, acid-rain, volcanos. etc.
This is based on the evidence so far presented and as such, is referred to
as scientific theory, though it is not without problems and questions still
unanswered. The more recent ice age, which caused massice extinctions,
could also be said to be due to impressive loss of habitat, habitat and
ecosystem being a combination of biotic and abiotic forces. Other
extinctions due to climatic change, or sudden change in sea level, would
also suggest a dramatic shift in habitats.
Most mutations die out because they fail in the way of reproductive
fittness or superiority, and species have certainly gone the same route,
with the loss of a major food source or pollinator and the lack of the
right mutation at the right time in order to "adapt." However, it would
crertainly be safe to say that in recent history, i.e. since man came into
the picture in a big way, there has been an impressive increase in
extinctions, and much of that has been due to loss of habitat. Certainly
the arguments can be made.
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