I'm not a creationist, but I'll try to answer within
that framework rather than imposing my view onto your
comments.
The organisms that we see on the planet at the moment have
a great adaptaive capability. When situations change
and different members of the population find it easier
to survive they and their offspring become the norm. The
populational content has changed.
From a creationist perspective all of this adaptability was built
into organisms by God. Why else would it be there, if not to
allow creatures to change over time, to adapt to different ways
of life.
From the creationist point of view, the creatures were created
with an adapaptability that they have utilised over time
to produce what we see now as diversity.
Another possibility, one of my own interpretation of the
bible, is that the Garden of Eden was not all there was. It
was a special enclosure for God's chosen group. Gen 1:1 describes
the whole creation including the making of mankind ... then
Gen 1:2 talks about the creation of Eden and Adam ... and God
bringing all of the animals to Adam to be named. The only
way to rationalise the discreprancy is to consider that the two chapters are talking about different things. This view helps
to understand where Cain's wife came from later on, and why there
are predators (from outside Eden).
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