Re: Vampire-osaurs?

[Tyrberg Tommy <tommy.tyrberg@aerotechtelub.se>]

Christopher Taylor Wrote:

>The only known poisonous bird, AFAIK, is the pitohui, a small passerine
>from New Guinea, and a type of whistler (Pachycephalidae). Probably
quite
>derived within birds, so not informative about stem forms.
>    The venom (which I don't think is very strong) is secreted in the
>saliva, and enters a wound passively when the bird bites. Seeing as I
would
>suspect the pitohui to be insectivorous (I don't actually know, but all
>other whistlers are), I suspect the toxin is probably used defensively
- a
>nasty nip to a potential predator is even more effective a deterrent
when
>accompanied by an annoying itchy, nose-swiping numbness.
>    Most interestingly, the pitohui's toxicity was only discovered
quite
>recently - early 1990s, I think. Sometimes, when it comes to places
like<
>Papua New Guinea, we know so little about the animals happily living
and
>thriving there that they might just as well have been extinct for 60
million
>years :-S

Just for the record, pitohuis are middling-sized passerines. There are
several species and their toxin is secreted in the skin to make them
unpalatable to predators. It is incidentally a very potent toxin though
present only in small quantities.
Do you have any reference to their transmitting the poison by biting? I
should think it would be quite a feat to get bitten by a pitohui, since
they are rather shy birds. You hear them all the time in the rainforest
but don't see them very often.
I quite agree that pitohuis are quite derived within passerines (and
birds), but they do show that producing potent toxins is physiologically
possible to archosaurs.

Tommy Tyrberg