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Re: Audobon bird/dino article
Betty Cunningham wrote:
> 2) He includes animals in his arguments against a close bird/dino
> relationship that we HAVE NO FOSSIL EVIDENCE FOR as gospel scientific
> proof for an argument.
> "Well, any engineer will tell you that's aerodynamically
> impossible. In every group of
> animals that flies or glides-BATS, frogs, snakes,
> squirrels-it's evolved from the trees down."
> a)What possible evidence does he have for bat origins? Everything we
> have that's been identified as a fossil bat is because it has batwings
> and already flies. WE HAVE NO FOSSIL RECORD FOR WHERE BATS COME FROM AT
It is correct that no fossils are known that tell us about the
beginnings of flight in bats. However, I suppose that in this case it
is highly probable that flying started as some kind of gliding in the
trees. There is another group of living mammals (the order
Dermoptera with the East Asian genus Cynocephalus) that is still in
this evolutionary stage of gliding, with no active flight. These
animals have even been considered as close relatives of bats. There
is no other way of starting something like flight in early bats that
I could imagine.
However, birds / dinosaurs represent a wholly different case:
Bipedal dinosaurs could have attained the necessary speed for taking off
by running, especially dinosaurs as well adapted for running as
dromaeosaurs. Comparable potential (bipedal) ancestors are highly
improbable for bats (as well as frogs, snakes ... ), so it makes
little sense to compare birds with these groups.
Martin Jehle, Dipl.-Ing. (FH)