Re: COWBIRDS....SHUDDER & nest predation

[Bill Adlam <wa105@mead.anglia.ac.uk>]

pb wrote:

>As far as finding stronger evidence of non-avian dino nest-parasitism, I
>would definately raise my eyebrows over any discovery of two different egg 
>(or eggshell) morphotypes from a single nest.

But if the eggs can be distinguished after all this time, they could have 
been distinguished by the parents.  They would then have ejected the 
parasites, unless they were bullied into raising them.  Different egg types 
could be due to reusing another species's nest, if durable enough to last 
another year.

It's hard to see why it would be worthwhile for the parasite parents to 
take revenge on alert hosts.  Maybe it leaves more food for less 
discriminating parents nearby to feed to parasite chicks.  Or it might 
drive the pair off, to be replaces by another, perhaps less selective, 
couple.

                                                All the best,

                                                                Bill