[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

nectarivory/insectivory/frugivory -- a thought experiment re: archosaurs & bats

The echolocation ability of small bats receives the
attention in discussions, and neotropical flowers have
the ability to reflect sonar "blips" of the bats, thus
ensuring pollination. However, among all bats -- and
this holds true for extant dinosaurs, and pre-K/T
dinosaurs and pterosaurs -- vision and smell are also
important for foraging. Nectarivorous chiropterans
have reduced ears and nose-leafs, so they are, in
fact, using vision/smell above hearing, and this could
have been true among some feathered theropods and
their sympatric pterosaur competitors.
Consider, too: resource utilization among
theropods/pterosaurs/chiropterans means hunger will
determine what is eaten. A mouth adapted for handling
struggling prey does not mean the mouth will not eat
fruit, or a flying insect, or nectar. Frugivorous taxa
are larger, in the main, than insectivores, and all
are larger than nectarivores. Nectarivorous taxa have
reduced teeth and an enlarged tongue. A large megabat,
and even the nectarivorous phyllostomid bats, will
land on a plant as if it were an aircraft carrier, the
flower torn apart for the nectar...and I can see the
same with a small flying dinosaur or pterosaur. On the
other hand, living trochilids (hummingtheropods) and
glossophagine bats will hover above a flower, their
faces stuck in the flower, the nectar obtained, the
petals still intact, both feeders being efficient
pollinators. Could small pterosaurs hover like a
trochilid or a glossophagine bat? 
Hovering is energy costly, constraining the size of
the animal involved. Thus, it seems doubtful to me
that hovering among pterosaurs and pre-K/T feathered
dinosaurs existed. They could eat nectar, but
nectarivory may not have existed either unless they
did not destroy the plants in the process.
Is there any evidence as to the possible tongue
morphology and/or hyoid-lingual morphology of
pterosaurs and the feathered dinosaurs? Some of the
feathered dinosaurs emerging in the main from China
are remarkably small.
Another thought: nectarivores (be they bats or moths
or hummingtheropods) rely on an extensible tongue to
retrieve the nectar (moths with a straw-like
proboscis), and the faces of moths/bats/trochilids are
areas for pollen adherence. It is not inconceivable
that during the end-Cretaceous, the flying pterosaurs
and dinosaurs may have had faces coloured with pollen.

Do you Yahoo!?
Yahoo! Mail Plus - Powerful. Affordable. Sign up now.