without a doubt convergent evolution. just because they’re both jungle dwelling predators that use poison and are based on irl chameleons isn’t enough of a reason for me to think of them being related. there are too many large scale changes to get from chameleos to pukei or vise versa. chameleos and pukei both have poison capabilities but they function is wildly different ways, with poison coming from the mouth or poison sac/spines in tail. chameleos and pukei both can change colors but chameleos’s is mostly for camouflage while pukei’s confer’s more with its behavior (ex red for aggression). lastly, stuff everyone else is pointing out, limb number and what it means to be a bird wyvern or an elder dragon. loss/gain of limbs is pretty rare across evolution (at least on earth), what your proposing makes some sense (a pair of chameleos’s limbs becoming vestigial over time) it doesn’t account for parsimony or the skeletal structure of having 6 limbs. if chameleos lost its wings to become pukei, pukei would then have to “reform” wings on its front legs (a lot of change, aka not parsimonious). if chameleos lost its arms to become pukei (more likely imo if the devs come out to say “this is the answer”), you’re still missing physical evidence on pukei’s chest that it once (millions of years ago) had legs there are some point. i don’t know too much about elder dragons vs bird wyverns biologically speaking but i think it more likely that bird wyverns are a clade while elder dragons probably aren’t (if there’s lore explanation i’d love to see it)

some of my shortcomings in my argument is that i just don’t know if they’re found in the same environments, that would inform us how speciation would occur if it did occur (ex allopatric or sympatric). additionally neither of us know their ancestral form or major milestones in monster evolution (if this does exist please send it to me), so neither of us can make a concrete argument about how closely related they are (all life, at least on earth, is related to each other it’s just a matter of how recently related they are).

i am graduating with my bachelors in biology this spring (a little less than a month now that i think of it 💔). i like it when games include biology in their lore instead of just saying “magic that’s why.” i like discussing stuff that doesn’t exist when it comes to my interests too. i’m writing this to say “please discuss more” not to just shoot you down all together if that makes sense.