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Post by lepidofrance on Jul 19, 2011 15:09:27 GMT -8
By the way, I don't know if Papilio ulysses is unpalatable, distateful or toxic for predators (I never been told about his toxicity), but what I know, since I saw this butterfly flying in Papua, is that ulysses produces the same flash effect (like Morphos) which certainly confuses the predator bird. Anyway, many ulysses are damaged and present birds attacks marks. Probably, it's the case for this one. Attachments:
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Post by lepidofrance on Jul 19, 2011 15:32:32 GMT -8
It's almost the same thing with Papilio lorquinianus : dark underside and blue-greenish metallic upperside. Morphos, P. ulysses, P. lorquinianus, Prepona, Archeoprepona, Memphis, all these butterflies show blue metallic irridescence which is very cryptic in forest biotops. I would say that's also a close way to escape predators with transparent butterflies (Ithomiinae, Cithaerias, Haetera) : they shine while passing through a sunny place and vanish as soon they go into the shadow. Do the experience : try to follow an ithomiinae or a Cithaerias into an amazonian forest ... ;D ;D Attachments:
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Post by prillbug2 on Jul 20, 2011 14:05:11 GMT -8
On the other hand, we find metallic silver in Chrysina (Plusiotis) spp. The silver acts as a mirror when the beetle is in the foliage, and reflects the green. Try finding them. A friend of mine told me that one day he was searching food plants, and suddenly, he was staring at a beetle that he had missed seeing only a few moments ago. The same effect was seen in Chrysina cupreomarginata which is actually metallic gold. They hide effectively because of the mirror reflection, even though some birds and reptiles might be able to capture them for food. Also, I have seen gold in several Rutelines that I have from China. Metallic green just blends right in. Iridescent green is the same way. I had found a Buprestis rufipes in 1973, and I didn't see it until it moved in the foliage, despite the yellow markings on the pronotum and elytra. Calosoma scrutator and/or wilcoxi are impossible to see when they are climbing in the trees during a caterpillar outbreak. But, birds still find them, and I have seen elytra and pieces of the exoskeleton resting on the ground below the trees, where the birds had dined. It's pretty much the same with blue in most beetles. On the ground or plant, the blue looks black, and the insect blends into the background. Again, it's the use of crypsis to fool predators. It applies in all of the orders. Jeff Prill
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Post by jshuey on Jul 22, 2011 5:35:49 GMT -8
Hey - I thought that I would add this photo - a simple demonstration of a bug that is pretty much "black" when on an insect pin, but out in the wild in direct sunlight - strongly irridensent.... j Attachments:
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Post by wingedwishes on Jul 26, 2011 9:56:00 GMT -8
Blue being more prevalent in the tropics makes me wonder that under a canopy, where it is darker, is it harder to see. Blue wavelenghts of light might appear nearly black and be harder to see in very low light conditions.
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