[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
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
cats are nocturnal, and house cats are generally diurnal as a result > of
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
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
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...
The new MSN 8: smart spam protection and 3 months FREE*.