[Ichneumon]

An interesting note here: The Monarch butterfly's caterpillars, through eating the milkweed plant become very bitter tasting to birds. A young bird will try to eat one of these, then gag violently. It will never even touch that caterpillar again. So, evolving a tolerance for the alkaloids in milkweed also turns out to protect these caterpillars from predation. The effect continues on to the adult. Here's another interesting note: Another butterfly looks very similar to the Monarch. It is also avoided by predatory birds, even though it doesn't ever ingest the milkweed.

That's the Viceroy butterfly, which looks amazingly like a Monarch, even though it is not at all closely related, and feeds (as a caterpillar) on willow tree leaves and not on milkweed. Monarch butterfly on the left, Viceroy on the right:

These two species are different enough, other than the superficial similarity in coloration, that not only are they in different genuses (Danaus vs Limenitis), they're in different subfamilies.

And the divergent nature of the two species can easily be seen when you compare their chrysalis, caterpillar, or egg stages (in each pair the Monarch is on the left):

Again, evolution is an amazing thing.

Yes it is.

[Quark2005]

I never cease to learn from your posts. Thanks again.