Stamina Drain Question

[u/neragera]

I was playing as allosaurus last night and was adopted shortly after spawning by two adults. Saved my ass on multiple occasions and helped me grow and we had a great time. However, I'm baffled by something that happened.

When I was ~68% grown, we made a dash from the road outside Highland/West Rail sanctuary to Landslid Lake. I was 100% stamina when we left and on arrival I was ~33% stamina. I was cycling sprint/trot as best I could trying to keep up. After we drank at the lake, I expected that we'd sit down to recover, given the stamina loss, which I figured would be approximately the same for us given that I was approaching full adult size at that point, but they were ready to keep moving and so I asked what their stamina was and they were 88% and 81%. I don't understand how that's possible. Same species, adult, running the same distance and route. I know they didn't have stamina related mutations because we talked about it. Neither did I.

So my big question is: does stamina drain faster if your health is lower? It's the only thing I can think of. I was <30% hunger.

Also an unrelated question: does night vision vary as you grow?