GotButterflies wrote:I've never heard that LadyJinglyJones. That's interesting. I've always heard that whatever has eaten Monarch caterpillars or butterflies will either get really sick and or die (insect/small animal wise) and that the toxins in the milkweed is why.
It depends on what insect you're talking about; vespid wasps and several kinds of ants predate adults and larva; some assassin bug types predate larva, as well as some spiders; specialist tachinid flies parisitize larva, as do the ubiquitous parasitic wasps.
Some critters that eat monarch larva have been seen to get kind of dopey after, like spiders that can't weave webs properly after a monarch snack. So it probably depends on the animal. I think it might also be the case that younger larva, with less stored milkweed chemical, are preyed upon more often - but there are quite a few insect predators that do eat them.
Plus, different milkweed species have different amounts of toxicity.
So here's the interesting part: cardenolide glucosides are the heart-arresting toxins found in plants, like milkweeds, but also others too. I got curious if there was research into crustacians & cardenolides.
And there is: Birgus latro (coconut crabs, related to coenobita) are sometimes poisonous to humans. The most toxic parts of the crab are the hepatopancreas (a digestive gland) and the intestines... which suggests that toxicity is derived from foods they eat. (You can see where this is going.)
In places where the crabs are eaten, starving the crabs before they are consumed is thought to make them safe. Traditional knowledge has it that the crabs feed on the deadly poison seeds of a plant called the Cerbera mangas,
which in turn makes them poisonous. These plants produce cardenolide glucosides.
So! While this in no way proves that milkweed is safe for hermits (maybe it isnt), because there are a number of different kinds of killer cardenolides, and different ones may affect different crabs in any manner of ways, it certainly adds to the knowledge of the kinds of things some coenobitids can handle. And I think that's neat.
Sorry for the long post!
