I think it's really weird that some of the "dragonewts" turn into Lizardmen with wings, while others just look like humans. It would have made more sense if they'd just evolved into two different kinds of monsters.
I guess they have two separate evolution paths. I imagine the boosts they got were different as well. Kind of reminds me of Kumo desu ga, where the MC is given different kinds of evolution paths to choose from when leveling up.