Stephen A. Karl
karl at CHUMA.CAS.USF.EDU
Fri Sep 29 08:57:29 EST 1995
Just for a little unabashed self promotion:
Ed Heist wrote:
> ... intergeneric hybrids among
> vertebrates are rare, and that I am aware of studies in which attempts
> to produce intergeneric hybrids in vertebrates resulted in successful
> fertilization but abnormal development and death of the embryos, just
> the phenomenon described in the original post of this thread.
Actually, we have documented (and continue to document) several
_natural_ marine turtle hybrids (Journal of Heredity 86:262-268 1995). We
have claimed that these are potentially the oldest natural hybrids known.
The earliest pair-divergence time is ~10 mya and the oldest is ~50+ mya.
A green/hawksbill turtle hybrid (50+ mya) held at Cayman Turtle Farm was
shown to have motile sperm and was seen mating with resident green turtles
(Fern Wood pers com.). In addition, the we have information on some new
hybrids (discovered and identified by Anna Bass @ Uni. Fl.) which are most
definitely _not_ F1 hybrids (the J. Heredity individuals were). The
extent of this hybridization is unknown, however, preliminary evidence
suggests that hybrids are being (and have been) produced in marine
turtles and that these hybrids are viable & fertile.
It should be noted that marine turtles are considered to evolve
somewhat more slowly than other vertebrates, however, the divergence
times that we are dealing with are quite considerable.
Department of Biology
University of South Florida
4202 East Fowler Ave, LIF 169
Tampa, Florida 33620-5150
Voice (813) 974-1592
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EMail Karl at .chuma.cas.usf.edu
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