Rat that Applies Poison to its Fur

The African crested rat applies tree poison to its fur to make itself more deadly.

The researchers made their discovery after presenting a wild-caught crested rat with branches and roots of the Acokanthera tree, whose bark includes the toxin ouabain.

The animal gnawed and chewed the tree's bark but avoided the nontoxic leaves and fruit. The rat then applied the pasty, deadly drool to spiky flank hairs. Microscopes later revealed that the hairs are actually hollow quills that rapidly absorb the ouabain-saliva mixture, offering an unpleasant surprise to predators attempt to taste the rat.

Posted on August 12, 2011 at 11:13 AM • 12 Comments

Comments

LenAugust 12, 2011 12:32 PM

I don't get it. Is this to defend the rat from squid predation? What's the squid connection?

Or is this item supposed to be some sort of security allegory? The rat represents DHS?

Confused.

MuffinAugust 12, 2011 1:11 PM

The African crested rat applies tree poison to its fur to make itself more deadly.

I love how you included the word "more" there. ;)

Dr. I. Needtob AtheAugust 12, 2011 3:22 PM

It's fascinating, but I would have expected to hear about this from Jerry Coyne or P. Z. Myers rather than Bruce Schneier.

Bruce SchneierAugust 12, 2011 4:41 PM

"I love how you included the word 'more' there."

I meant to write "dangerous."

BacopaAugust 12, 2011 8:57 PM

Monkeys often wipe their butts with strong smelling herbs to repel mosquitoes. I saw a monkey wiping his butt with a green onion once. Some birds squeeze venom out of ants to repel bird lice. Urban birds will use lit cigarettes to repel lice. But this is the first I heard of a rodent doing something like this. Makes sense though, rodents are sometimes pretty sharp

markAugust 13, 2011 1:56 PM

Interesting rat. I just wrote today about how possums are resistant to rattlesnake venom, and one of the lists I saw of other resistant creatures included a few different types of rats. Also meerkats, mongooses, and hedgehogs. I think several prey animals have developed venom resistance and maybe this rat has something similar?

tommyAugust 13, 2011 11:54 PM

@ Len:

"I don't get it. Is this to defend the rat from squid predation? What's the squid connection?"

None. This thread is not the Friday squid thread. This Friday's squid thread is:
http://www.schneier.com/blog/archives/2011/08/friday_squid_bl_289.html


@ Bacopa:

"Monkeys often wipe their butts with strong smelling herbs to repel mosquitoes..."

Works for humans, too. If you are going to enter an area thick with mosquitoes (swamp, etc.), crush a fresh garlic clove and rub it all over your skin. It really, really does repel mosquitoes. Probably repels people, too, but if everyone else does it, then no one notices. It's also much less harmful than toxic sprays.

RogerAugust 14, 2011 4:36 AM

There are now many known examples of poisonous animals that are believed to borrow their venom from other animals (but few are considered "proven.") Examples include poison dart frogs and the pufferfish.

While it is remarkable that this animal has a structural adaptation to maximise the impact of the poison, the same is true at least of the frogs. It is also not the only mammal to re-use another species' venom.

kingsnakeAugust 15, 2011 5:07 PM

"If you are going to enter an area thick with mosquitoes (swamp, ", Wisconsin, "etc.) ..."

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