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Re: the opposite of paedomorphosis?



> So, if paedomorphosis is the reduction in overall size, rostrum length
> and such due to sexual maturity while in the juvenile stage, what is the
> term and process for rostrum lengthening, neck elongation and overall
> size increase?
>
> No jokes about the 'awkward age' in teenagers, unless pertinent.
>
> I've read it about this. I just need a reminder and perhaps a ref.
>
The opposite of paedomorphosis is peramorphosis. However, paedomorphosis
isn't exactly what you describe. It is simply the collective term for
evolutionary trends in which descendant forms retain characteristics found
in juveniles of the ancestors in to the adult state.

Paedomorphosis includes such phenomena as neoteny, progenesis, and
postdisplacement; peraomorphosis includes acceleration, hypermorphosis,
and predisplacement. The whole shebang is "heterchrony": evolution by
changing of timing of development.

                Thomas R. Holtz, Jr.
        Senior Lecturer, Vertebrate Paleontology
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
        Mailing Address:
                Building 237, Room 1117
                College Park, MD  20742

http://www.geol.umd.edu/~tholtz/
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796