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Re: Lepidosaur cuteness factor?

Two of the examples have adults with orbits longer than rostra. In the
third rough proportions do not significantly change. Sure the adults
have horns, dorsal frills, etc. Shapes square off abit.

It is as I said: all the above is true, yet still the juveniles are always cuter than the adults of the same species (bigger and rounder eyes, smaller snouts). Hey, even for us it applies, even though we have shorter faces at any point in life than any lepidosaur hatchling.

In short, there's nothing wrong with using skull proportions for phylogeny -- _but only if_ all OTUs are at the _same_ ontogenetic stage (which is probably impossible to test unless all are adult). So when you have potentially ontogeny-related characters in your matrix, code all suspected juveniles or subadults as "?" for them, or the cladogram will be garbage. (Perhaps just a few bootstrap values will be somewhat off, but perhaps the entire topology will be artificial. It can even occur that totally wrong clades will have high bootstrap support -- Chippindale et al. in a recent Systematic Biology issue, title begins with "Ontogeny Discombobulates Phylogeny:", using the real example of metamorphosing and non-metamorphosing urodeles.)

Even in Pterodaustro the rostrum lengthens proportionately
during ontogeny.

Hard to avoid.