[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Dinosaur subspecies names?
Hmmm... okies. From what I know.
(tosses in my two pennies into the circle)
There are some different animals that can breed together.. ex. Mule Deer and
WhiteTail Deer(get viable offspring too, fertile). But, this doesnt happen
that often. Reasons are that different sexual displays, mating times,
behaviors. etc all play into this role. Why they are seperate species. you
can do the same with a wolf and a dog(get viable offspring too, fertile);
dog and coyote(get viable offspring too, fertile). Just cause the can have
viable of spring doesnt necassarily make them the same species. Normally
they wouldnt breed. :?)
And its probally the same for,C.c.cornix and C.c.coron.
Anyways thats it.<shrugs and goes back to lurk mode>
On Sat, 24 Nov 2001 22:53:17 -0000, Mike Wall wrote:
> Gorgosaur@hotmail.com (Oyvind Padron) said:
> >>And, indeed, there is a long standing debate over whether _C. corone_
> >>cornix_ may in fact be different *species*:
> >if you dig up the good old taxonomy rules from high school, we learned
> >in order to be a different species, the different animals can't get a
> >fertile offspring.
> >C.c.cornix and C.c.corone can easily get a fertile offspring.
> Shame that the 'good old taxonomy' books got it all wrong according to
> current thinking.
> How do you treat ring species, for example, Greenish warbler
> trochiloides _. This old world warbler is theorised to have originated
> of the Tibetan plateau. As a result of climatic changes, it was able to
> extend its range west and east, then north on both sides of the plateau.
> Eventually western and eastern populations meet in a central contact
> north of the plateau. Genetic and morphological changes have occurred in
> population as its range extends, such that there are a number of
> recognisable subspecies throughout its range, each of which can mate and
> produce fertile hybrid offspring with its immediate contact neighbour.
> However where the westward/northward population meets the
> eastward/northward, the races/subspecies of the species have diverged to
> such an extent that they are reproductively isolated and behave as
> species. Ornithology is currently split as to whether to treat the
> north-eastern subspecies as a full species (Two-barred Greenish warbler
> _P.plumbeitarsus) and if so, what then to do with other subspecies.
> E, Bensch S & Price T D 2001: Speciation in a ring. Nature 409:333-337).
> Presumably similar events have occurred in the past, with the splitting
> joining of continents, mountain building etc but gaps in the fossil
> would make this difficult to prove.
> What about species that are normally geographically isolated? Ruddy duck
> _Oxyura jamaicensis_, from North America and White-headed Duck _Oxyura
> leucocephala_ wouldn't normally meet, unless man hadn't introduced the
> former into the UK in 1950s. Now the ruddy duck is allegedly threatening
> WHD through inbreeding. Does this make the WHD a 'bad' species?
> Species nowadays are generally considered 'good' when, where a contact
> exists between two types, only limited interbreeding occurs (how limited
> needs to be is open to interpretation)
> All the best
> Mike Wall
> Hants, UK
Paleo Mont - www.geocities.com/paleo_mont
Paleo Mont Park - www.geocities.com/paleo_montpark