Interesting Ideas Brent,
It was a horrible day here in SW ontario, so i had a little time to frog watch. I was able to observe interactions between a female green pumilio with a tad, and a male without. The male was calling frequently while sitting on top of some leaves, he was "prancing" around in circles in the same spot on these leaves, very shortly later the female emerged from within these leaves with a tadpole. he called even more now. For a while there was what seemed normal interaction, calling here and there, female looking for food etc. About two hours later i came back and male was calling from a bromeliad funnel. i looked closer and could see the female submerged further down depositing the tad. Later in the day male is back in the same funnel calling away.
In this case it seems evident that male is aware of where the female is placing tads, so they perhaps share the same mental map, and the male perhaps will beckon her to feed as needed. Now the problems with the observations as i see it are they are from a tank with just one pr of frogs, by keeping just one pr of frog/tank we are ensuring monogomy. the observations taken at face value would seem to indicate the potential atleast for some sort of pr bond to forming, as it seems there is atleast some communication between male and femle during the development of the tadpole, as with faculative egg feeders. If this same "bond" were shared with wild prs, would this also ensure monogomy? An interesting question would be if these same behaviours would take place in a large viv. with oppurtunities for polygymy, would the male communicate with two females, with none? What does this say in general about breeding habits of these frogs, it seems that they (males) are more involved, but is this just due to raising them in prs in captivity. How does this play out in the wild? Will males have maps of locations from more than one female if polygymy is proacticed, or does polygmy alter this behaviour we are seeing atleast in prs in captivity.??
As for why there are two mechanisms, I can't say, or see how one would benefit over the other. In blue jeans pumilio i have only ever seen female transfer tads, and basically the male dissapears while she raises them. An occasional squak or two but basically I dont really see him till the female is ready to breed again, then the incessant calling starts, with these prs i can usually count on finding tads when i notice the male has stopped calling.
Im struggling to find a point here, i guess it would be is that maybe its possible for these different types of pumilio be heading down divergent paths?? or is keeping them in captivity altering there behaviour. Brent you are far more knowlegeable of behavioural ecology than i ever will be so i would love to hear more of you thoughts on this. And anyone else's for that matter.
Its fascinating that the most studied of all dendros still has some surprises to yeild.