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Old 03-23-2020, 09:04 AM
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Tiny flying endotherms and heat loss


There's major buzz about oculudentavis, and whether it was in fact a bird and not distantly-related reptile who convergently evolved a bird like head.

Those in favor of the latter cite the dentition as being non-dinosaur like, in addition to how far back they extend posteriorly to the eyes.

No-one seems to be bringing up how a flying dinosaur could not succumb to hypothermia at such a tiny size. If I'm not mistaken extant birds only get so small before they hit that barrier, and only hummingbirds "break" it by drinking copious amounts of energy-dense nectar.

The emergence of flowers was from the middle-to-late Cretaceous, oculudentavis is from 99 million years ago, well before any selective pressure to feed on nectar emerged. Even if flowers were around for longer than is thought, the animal doesn't seem adapted to nectar feeding anyways.

Then I thought of of Kitti's hog-nosed bat; weighing in at an average of 2 grams, it is only slightly larger than the 1.9 gram bee hummingbird. What's more, sources claim that, unlike other bats, kitti's bat does not huddle for warmth when at rest. It doesn't eat nectar, so how did it exist?

Is it because they eat at a narrow window of time each day, thereby conserving energy? If so, what would prevent a diurnal bird from doing the same? Could it be the cave environment that makes the tiny bats harder to pick off, than if they hanged out in trees like birds?

Is it the time of day in which they hunt, making them less easy to be hunted? Moreover could their drabness help, presuming typical bright plumage would be present in male oculudentavis, whose eyes betray a lack of night vision?

Could it be that body surface area plays a part, particularly with wings either in flight or at rest between bats and dinosaurs?

Last edited by Trancephalic; 03-23-2020 at 09:04 AM.
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Old 03-23-2020, 09:23 AM
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Surely, it'll depend on the climate they live in?
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