Lately I read an article about a specie of insect that had disappeared 80 years ago and had re-appeared lately somehow.How can it be? Would it be possible for an instinct specie to reappear just by the wish of mother nature?

I'd imagine that it would be due to where it lived - e.g. not in an area that has a lot of human movement.

It could be that it wasn't extinct but its numbers were so low that no one could find it.

I suppose it is possible for a species to re-evolve, but not in only 80 years.

Matiqua is correct. I believe you are referring to the Lord Howe Island phasmid, which was thought to have gone extinct after rats from a shipwreck invaded the only island on which it has ever been found. Its 'reappearance' consists of a population with a grand total of 24 members on a large rock 23 kilometers from Lord Howe Island.
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This is fascinating but it's okay by me if a T-Rex doesn't pop up! I can honestly say that not all vanished species are missed.

[This message was edited by Kelleygirl on 11-16-03 at 12:26 AM.]

No need to worry about a T-Rex Kellygirl, they wouldn't have survived the ice age. However, if someone actually does manage to clone dinosaurs from fossilized sap...

Really interesting, good thing humans are not "parthenogenesis",

I'll drink to that, Mozart!