Re: transitional fossils

> It is false to claim that all species appear abruptly in the fossil
> record and then persist with little or no change. If we have good,
> detailed information for a fairly continuous section of time, we see
> some species that have little or no change, some species that vary a
> bit, and some that show clear trends. Any of these may also have a
> transition to a new species during the observed interval.

Thanks. It would be nice, however, to know more about what you mean by
"clear trends." Do you mean things like ring species or changes in
foraminifera, radiolarians and diatoms? The diatom history clearly shows
morophological change, but then again, no one would say they are no long
diatoms. I'm looking for something a bit more substantial.
Received on Mon Dec 5 17:32:27 2005