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Re: non-extinction

"Mike Styzen  Shelf Expl, <mstyzen@shell.com> wrote: 
On non-extinction

>What about the vertibrates that made it through? did they really sail
>right on by whatever happened as implied?  Or did they scrape by by the
>skin on their teeth like the nannos did?

Birds got plastered at the K/T boundary.  Big-time plastered.
According to fossil bird expert Alan Feduccia in _Science_, vol. 267, Feb.
3, 1995, pp. 637-638,  the major orders of birds got wiped out at the K/T
boundary.  Only a small, previously minor group of birds (probably a
monophyletic group of birds) slipped through: Neornithes.  After the K/T
boundary, Feduccia claims that most modern orders of birds appeared within a
period of 10 or so million years.  Song birds didn't appear and diversify
until the Miocene (40 million years after the K/T boundary).

Mammals didn't fare any better.  There was a radiation of therian mammals
prior to the K/T boundary, so studying the so-called "explosive radiation"
of mammals above the boundary gets a little complicated.  Cretaceous-esque
mammals existed well into the Tertiary, but in very dimminished numbers.
For instance the multituberculates were the dominant small mammals of the
Mesozoic, but became small-time bit-players in the Tertiary.  "Multi's"
hung on until the Oligocene.
  For 10 million years after the K/T boundary, there were NO large
carnivoran-type mammals.  Or at least none have been found yet.  It looks like
things got out of whack for the Mammalia too.  Malcom McKenna wrote a good
summary of the radiation of mammals in _Natural History_ last? year.
It was either in 1994 or 1993.  I recall that Novacek had something in that
article also.  The articles were meant for the general public.