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Re: pterosaurs, bats, flying theropods

But, it is a generality. Only one select clade, Microchiroptera (which
is possibly polyphyletic with regards to Megachiroptera), is generally
nocturnal, with some diurnal microbats, and all megabats are diurnal.
Arguing that bats are nocturnal is in fact an error on the order of a
generality that does not hold true.

Frankly speaking, I have never seen a chiropteran, whether micro- or mega-, that was flying about in broad daylight. Can you provide me with any info as to which species have actually been observed as being diurnal?

And 'all' megabats being diurnal??? I don't think so. In my country (Singapore; shameless plug: recently featured in the Amazing Race 3), we have 3 to 4 species of megabats, ranging from relatively large flying foxes to dimunitive nectar bats, & none of them have been seen leaving their roosts at least before 6 pm.

Do you define 'diurnal' chiropterans as being wholly diurnal, or merely being generalists who couldn't care less whether the sun was up or down before leaving the roost?

Or does the definition of being diurnal include those that are crepuscular ie those that are active at sunrise & sunset? Maybe certain bat species which are merely early risers (relatively) & up and about b4 dusk have been misinterpreted as being diurnal.

Whatever the case, to me the generalisation that bats are nocturnal still holds, at least in this part of the world :\

Cats would be seen as diurnal hunters, as all big cats are generally diurnal hunters to the possible
exception of leopards (*Panthera onca*), but this is also a generality, as most small
cats are nocturnal, and house cats are generally diurnal as a result > of their habitat.

Wrong. All cats, large & small, do a high proportion of their hunting at night. Of course, it varies from location to location, for example, Serengeti lions are perfectly comfortable with both daylight & night hunting, while the lions of Savuti will only hunt at night. But it is safe to say that with the exception of the cheetah, a high proportion of cats' kills occur at night. Diurnal hunting is more or less a misconception perpetuated by documentary film crews & researchers unwilling to venture out at night.

It is astounding to see how flexible many large mammals really are in their habits. In many cases, it is hard to truly define them as nocturnal or diurnal. We like to pigeonhole animals by their habits, but the truth is, nature does not package her animals this way.

This raises an interesting question: Has anyone looked into how nocturnal dinosaurs may have been? So far I have only read about the possibility of troodontids being specialised for hunting mammals in the darkness, but what about the other dinosaurs? Could they have been as flexible as many large mammals are today, being comfortable whether it was day or night. Too bad we don't have fossilised retinas from dinosaurs. If only we could check to see how many rods or cones dinosaurs had...

By the way, the leopard is Panthera pardus. P. onca is the jaguar.

But there is not but one avian body plan, but many of them. Owls,
oilbirds, nighthawks and goatsuckers, etc., have shortened faces with
large, forward facing eyes, and renowned hearing, good for nocturnal
living, with specialized feathers for making little to no sound during
flapping, good for night hunting, and all these have zygodactyle feet,
broad tail fans, and variably shaped wings.

Do frogmouths have broad tail fans? And if I'm not wrong, some species of swifts do their hunting at night. I don't think swifts have broad tail fans...

Soaring birds have reduced flapping musculature and their arms are proportioned for flight, and nearly all have webbed feet, alluding to > their ancestry. And the list goes on....

Correct me if I'm wrong, but the last time I was looking at an eagle soaring, it... had no webbed feet!

Besides, which birds are true soarers? I can only recall birds like albatross, raptors, cathartids, (do frigate birds soar? How about gulls?)

Furthermore, I have seen several instances of crows soaring, using the upwellings of hot air rising from hot tar roads (something like thermals I suppose) and these still have very strong flapping capabilities...



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