Polly want a poison?

[Fishteacher73]

I was reading today that in the entire living world, there is only one class of animals that does not have at least one of its members being venomous or toxic. This class is Aves, or birds. Anyone with any contradictory information? Anyone have an idea as to why this would occur? (Or specifically since toxicity is a well proven and wide spread trait, why did it not develop in birds?)

[bumab]

Perhaps the lack of a delivery mechanism- in most cases, it's either teeth or a spiny appendage. Birds have, nor ever have had (?) any sort of thing like htat

[Fishteacher73]

You have tallons, which would be very easily adapted, IMO, into a delivery mech. The beak has gone through may adaptations. There are not even toxic flesh or glands to make it poor tasting, such as a toad.

[bumab]

True. I ran out of time with that last post, had to quickly get off line, so it was an incomplete post...

 

I can't think of any animal that's evolved poison from their talons (or claws). Is there an obvious one I'm missing? Could be because most folk think poison fangs evolved from poison saliva- an already present adaptation. Poison spines probably evolved from poison skin, an already present adaptation.

 

And perhaps birds simply don't need to be poisonous. Birds are relativally fragile, poisoning something, then getting away without getting hurt might be a little to much. And they probably taste bad already- all those feathers make them pretty un-nutritious for the amount of effort it would take to catch one...

 

Really, I don't know... :) Good question!

[MortenS]

I did find some birds that are toxic:

 

Apparently birds in the genera Pitohui and Ifrita on New Guinea carry batrachotoxins.

They probably store these as they eat insects of the genus Choresine that also contains this toxin.

 

Source: http://www.sciencenews.org/articles/20041106/fob3.asp

 

Claim refuted? :)

 

PS: These are the two only known poisonous birds...

[Fishteacher73]

True, avian agility, which is probably their greatest assest, would be hampered by extra mechanisms that would not be as effective as their original agility.

 

Most avians are not preaditors either, and they use their skills in flight to obtain prey, and not need a mechanism to stun its prey.

 

Just an anomoly that had popped up in a book and I wondered about. Thanks for the insight, bumab.

[bumab]

Nice!

 

Although it's still not a bird that uses poison for hunting, or produce it's own (like a snake).

 

Certainly refutes the no bad tasting bird claim though.

[Fishteacher73]

This could be an argued point. Just as many sea slugs gain their toxicity from the food source, so do these birds. It seems that they do not utilize this toxicity though... I wonder if this counts...

Good searching Mort... :)

[MortenS]

Many poisonous insects get their poison from plants...whatever gets the job done :)

[MortenS]

could be that the toxicity protects it from predators and parasites, though...

 

PS: Digged some more and found this interesting paper:

 

http://www.colostate.edu/Depts/Entomology/courses/en570/papers_2004/sever.pdf

[Jut]

.

 

Certainly refutes the no bad tasting bird claim though.

I've just been reading "song of the dodo" and the author links to several sources stating that the dodo didn't taste too good :Alien:

 

As to the poison/toxin in bird thingys, it may have existed in the past before birds evolved into what we now recognise as birds (depends if you believe they evolved from dinosaurs or not).

[bumab]

I've just been reading "song of the dodo" and the author links to several sources stating that the dodo didn't taste too good :)

 

Heck, I don't really like pheasant. Must be poison. :)

 

 

As to the poison/toxin in bird thingys, it may have existed in the past before birds evolved into what we now recognise as birds (depends if you believe they evolved from dinosaurs or not).

 

I suppose it could have been a lost trait somewhere down the line. I doubt we'll ever know that, since evidence of a poisoning ability wouldn't fossilize to well, other then maybe a hollow tooth or something.

 

I thought the evidence for birds coming from dino's was pretty nailed down, with the hips, feathers, and various other lines of evidence. Has something new come up to discount that hypothesis?

[Jut]

 

I thought the evidence for birds coming from dino's was pretty nailed down, with the hips, feathers, and various other lines of evidence. Has something new come up to discount that hypothesis?

noot really sure to be honest, i still think there is some division on the matter as the missing link is yet to be found.........and nope archeoptryx (sp?) isn't that missing link unfortunatly. although it shares characters to both birds and dinosaurs, sharing characters does not prove evolution and its suggested that it is meerly a unusual bird not the "smoking gun".

[Tormod]

the missing link is yet to be found

 

Which missing link would that be?

[Jut]

between bird and dinosaur

[bumab]

although it shares characters to both birds and dinosaurs, sharing characters does not prove evolution and its suggested that it is meerly a unusual bird not the "smoking gun".

 

And what would a smoking gun be? Short of DNA, which we are most likely not going to get, I don't think it gets much clearer then a morphological comparision. Recently evidence has come to light that many other species of dino's had feathers, furthering the comparision, and providing more links. For example, velociraptors most likely had feathers- some think for insulation, some think it helped them run up steep slopes (which is how flight started). Regardless, they are another morphological trait that can be compared.

[MortenS]

While we do not have DNA that link birds to dinosaurs, we do have DNA that link to the next best thing: bird DNA are most related to crocodile DNA.