Re: Animals that are poisonous to ingestion Social Behavior

drosen0000 asks:

What finess value does being poisonous upon ingestion have to
animal prey? I am not talking about poison that is actually applied to
the predator by the prey biting, but to the passive ingestion of
posion.

There does not seem to be any advantage unless there is a
correlated social behaviour involoved. Once eaten, the prey is dead and
can't produce descendents anyway. If the predator dies, it does not
bring the eaten prey individual back to life. If the predator's species
dies, it still doesn't help the descendents of that prey animal since
there are none. If the prey animal species is not social, the
nonvenomous individuals are protected just as much by the death of the
predator as the venomous individuals. The venomous individuals have to
pay a metabolic penalty for producing the venom.

Some social behaviors that would make being poisonous to ingestion
a benefit to other members of the prey's family (e.g., selfish gene
scenarios). However, I never heard of a correlation between social
behavior and being poisonous. Do venomous animals tend to be social?
Does anyone know if poisonous frogs stick together in family groups?

It sounds as if you're trying too hard to fit your observations in with
a bit of simplistic mathematical genetics theory. On the whole, group
selection has nothing to do with altruistic behavior.

In general, the physics of mathematical genetics makes either the gene
or the individual the "beneficiary" of whatever behavior is under
consideration, but such a presumption is clearly not true for a large
array of observed behaviors, and the evolution of aposematism is one of
them. The "beneficiary" of a phyletic lineage evolving the standard
warning colorations of orange, yellow, black, red and white is the
lineage itself, not its individuals.

Individuals can be sacrificed if the benefit/cost ratio is high enough.
Evolutionary adaptation is a learning process, and there are three
reservoirs where that learned knowledge is retained: (i) in germline
DNA ("phylogenetic learning"), (ii) in the neural mass of the species'
individuals ("ontogenetic learning"), and (iii) in the the cultures of
the species' demes ("sociogenetic learning"). In this case, the
"knowledge" pertaining to the evolutionary advantages of aposematism is
retained in the lineage's evolving germline, and thus pervades the
genome of every individual it produces.

In your accompanying question, you asked how does the process ever get
started, given the death of the predator? The answer is simple. Most
poisonous animals are not lethally poisonous. Indeed, most are only
noxious. Monarch butterflies act only as an emetic to Blue Jays
(meaning that ingesting one butterfly makes the bird throw up), but
Blue Jays are quite smart and they quickly correlate the warning
coloration pattern with the noxiousness of the butterflies.

I doubt that Blue Jays have learned that information "instinctually",
meaning that it's not yet incorporated into their germline DNA. I
suspect that each individual bird must eat one or two Monarchs before
he gets the idea, but once he does, the death of those individuals
protects thousands of others.

It's important to understand that by having a vast number of animal
taxa all convergently learning to expose the same colorations if
they're even slightly noxious, they're all evolving against the same
adaptive topography, and in doing so, they're reinforcing one another.
In this case the adaptive topography is the eye, mind and intelligence
of vertebrate predators, and because of that, the protection that
orange, black and white colors affords Monarchs undoubtedly extends to
any similarly colored animal, regardless of taxonomic status. I'm sure
that Blue Jays, once bitten, twice shy, will stay clear of any similar
pattern.

Wirt Atmar


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