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Re: attack on dinosaur--horrific video
----- Original Message -----
From: "David Marjanovic" <email@example.com>
Racoon-size? How pathetic.
_Nanocuris improvida_ and _Cimolestes magnus_, both carnivores (apparently)
and both eutherians, and both "marmot" sized. Again, my point is that
mammals of this size (and even smaller) scale to non-avian dinosaurs
offspring in similar ratios as extant predators (mice vs. albatross, for
example) scale to extant dinosaur offspring. They may or may not have been
a problem before the boundary--it _is_ an interesting coincidence
I will just bring up *Repenomamus giganticus* again, which must have
ushered in the Great Barremian-Aptian Boundary Mass Extinction, except it
Anne Weil discusses this anomally, saying research is going on trying to
find out if dinosaurs at that place and time were smaller than usual.
Certainly there are selection pressures for being large or small. What were
they in each case? Dinosaurs were not smaller in the late K. Also, _N.
improvida_ and _C. magnus_ were very different creatures from _R.
giganticus_. I don't know that much comparison is afforded--other than the
interesting question of relaxation on size constraints enjoyed by both
clades, likely for different reasons.
Not even the crocodiles died out.
Are you certain that ground-nesting birds are generally night-blind?
I know an attended ostrich nest is practically immune from predation in the
day--but that, if discovered by black-backed jackals, they are invariably
destroyed at night, i.e., the ostrich can defend effectively in the day time
but not at night.