Precocial:
- (adjective) (of the young of some species of birds after hatching) covered with down, having open eyes, and capable of leaving the nest within a few days of hatching
- (noun) a precocial bird [Collins Dictionary]
That’s new to me. Noted in “Why dinosaurs lived much more complex lives than we thought (Interview with David Hone),” Michael Le Page, NewScientist (2 May 2026, paywall):
You study the flying reptiles known as pterosaurs as well as dinosaurs. Were these animals really able to hatch out of an egg and fly straight away?
[Hone: ]The idea they might be precocial, as it’s known, has been around for a while, but it’s only relatively recently, with the discovery of pterosaur embryos, that we’ve had good data that supports it.
If you look at birds inside eggs, they have well-developed feet, but they don’t have well-developed wings. Before pterosaurs have hatched, they’ve got long wings with strong bones, almost identical to the adult condition. That immediately points to the idea that they might be flying straight out of the egg.
Perhaps I won’t be working that one into casual conversation.
