What is convergent evolution?
Convergent evolution is when various species evolve similar
solutions to similar evolutionary pressures, independently and
often at different times in the earth's history. A good example is
the Ichsyosaurous(swimming dinosaur), sharks, and dolphins. All of
them evolved with a very similar torpedo shaped body. Another
example is the eyes of octopi and humans. They are alike in
structure and function.
The rare Tasmanian Beech tree is the only true deciduous tree in
Australia, and was long thought to be a relative of the northern
hemisphere species, but study of its DNA shows that its origions
date back to the Gondwana-southern supercontinent. So, the leaf
shedding strategy evolved seperately in both hemispheres, another
example of convergent evolution.