Natural History Question

[urbpan]

Toads (speaking here of genus Bufo) have poison glands, correct? I remember my mother's dog catching them and then vomiting (charming). Many animals that are poisonous to eat have warning coloration: poison dart frogs, tiger salamanders, monarch butterflies. Why are toads cryptically colored?

cross-posted to herpers

Comments

[vyoma.livejournal.com]

So the hippies won't lick them.

[vampyrusgirl.livejournal.com]

Great answer! :)

[agelena.livejournal.com]

A previous pet used to start foaming at the mouth as soon as she picked one up, so whatever the toads exude seems to be fast-acting. The toad doesn't have to wait to be digested to make the predator sick. If so, it' gets the best of both worlds: "You don't see me, I'm not here...." as well as "Ok, you saw me, but you're gonna spit me out in about 2 seconds."

At my house, their protective coloration means that I almost break my neck on a weekly basis trying to avoid stepping on them when I see them at the last possible second.

[aemiis-zoo.livejournal.com]

Yeah, what she said. ;)

My hypotheses (e.g. talking out my ass)

[aemiis-zoo.livejournal.com]

What I am thinking, is that perhaps toads evolved cryptic coloration as their primary defense, and the poisonous paratoid glands as a secondary defense and last ditch effort at saving themselves. It could be that the poison is biologically costly to produce.

And/or

Since many genes are conserved over time, it could that modern toads were derived from camouflage ancestors and developed the poison as a secondary defense.

At any rate, you have got me curious now, and I am looking into it.

This reference may or may not corroborate my thoughts Toxicity & Defense Methods of Amphibians. It's hard for me to tell. I haven't yet had any caffeine.

[cailin-t.livejournal.com]

all frogs have poisonous glands, yes.

[godstatic.livejournal.com]

The Bufo species, specifically the Bufo alvarius, contain "venom" glands, but its not venom, it's actually a methyl-oxy composite of a chemical we use to survive! 5MeO-DMT (5-MethylOxy-DiMethyl-Tryptamine) is the closest natural relative to DMT (Dimethyl-Tryptamine), which is the chemical created by the pineal gland that we use to sense the world around us (see, hear, smell, taste and feel), as well as the chemical we use to perceive emotion. It's the most guarded and sacred chemical in your body, protected by a chemical barrier, and two physical membranes, it is the VIP of the brain.

The Bufo toads produce three chemicals. 5-MeO-DMT, which has a similar effect on the brain as DMT, Bufotenin, another relative of DMT, and a mild toxin bitter in taste that makes most animals vomit. Virtually all Bufo toads produce these three chemicals, however only the Bufo alvarius produce 5-MeO-DMT and Bufotenin in great enough quantities to stimulate a hallucinogenic effect on humans.

Ultimately, the chemicals the Bufo toads produce are not deadly in the least. The secretion is there more as a last second defense to try and get the predator to spit the toad out since the taste of the secretion is so foul, and produces near immediate hallucination. Perhaps the coloration on the toad is its primary defense, with the secretion being a secondary?


I'm sure most of your friends are convinced I'm a raging drug addict, but I assure you that I approach every chemical in a scientific manner. Just as its your job to tend to and document animal life, it's my job to observe, encounter and document the complex relationship between humans and hallucinogenic chemicals, especially endogenous ones. :)

[gemfyre.livejournal.com]

The poison of Bufo marinus, the Cane Toad is lethal to many pets and Australian native animals. It was introduced in Queensland to control the cane beetle, but of course, the beetle could fly and the toad couldn't. And the toad rather like the Aussie climate, very similar to it's native Africa. It has now spread down the eastern seaboard and across the north and is getting closer to the Western Australian border by the minute. There is currently a HUGE campaign running here to control the toads and stop them from spreading further.

Luckily some native corvids have learned the "flip the toad" trick and it's been noted that some snakes are evolving smaller throats so they physically cannot ingest a toad, probably saving their lives.