Do we need a better concept than species?

I don't have any problem with people using species provided they make the neccessary effort to put it into the proper context. Problems only arise when people fail to make it clear how they are using the term. Failure to diferentiate between solely morphologically defined species such as we see in the fossil record and the extant species we study today on whom we have much more in terms of genetic data, and potentially interfertility, only leads to confusion.Similary failing to differentiate between the different forms of reproductive isolation, such as geographic isolation or pre- and post- mating isolation, can cause a lot of disagreement on what constitutes a real incidence of speciation.I think most scientists within a field can usually agree on what a species is, it is between the different fields that differences arise as the differing definitions are obviously biased towards the interests of the particular fields. Provided the particular context is made apparent there should be no need for confusion.TTFN,WK

That is why most studies on this sort of question talk about incipient speciation rather than speciation.TTFN,WK

I think you are right, 'event' gives the impression of some some of instantaneous occurrence when it is describing a process taking hundreds or thousands of years at least.In terms of paleontonlogy the punctated equilibrium theory posits that speciation 'events' occur in a 'geological' instant, i.e. in too short a time period to be resolvable through paleontological methods.TTFN,WKThis message has been edited by Wounded King, 08-05-2005 10:38 AM

Correct, unless these were samples recent enough to allow recovery of some gentic material, as in the case of the neanderthal mtDNA sequences. Such sequences might not completely rule out gene flow, but they could be suggestive. Generally geographic isolation itself is not considered sufficient to classify different populations as seperate species. If the two populations are subsequently reintroduced to each other and can successfully interbreed then they would not be considered to be seperate species under the biological species concept.The distinction is more commonly drawn between pre-zygotic, i.e. behavioural or morphological, barriers to reproduction as opposed to post-zygotic, i.e. physiological or genetic or developmental, barriers to reprodcution leading to either a lack of interfertility or a lack of viability or sterility in hybrid offspring.TTFN,WK