i have been reading through everyones post and this actually seems interesting but if 2 different species had the same DNA to make a crossbred child, wouldnt that mean at 1 point these fish MAY have been the same species???? because they have the same DNA
This is a good question. The 1970s era science most of us learned from (which was probably from school textbooks that had been around since the 1950s) pretty much taught us all that, by definition, a species was valid and separate from another if the two organisms could not produce fertile offspring. Animal and plant biologists have strayed from this definition, in varying distances among various life science specialties, over the last 50 plus years.
Ironically, the only group of living beings on the planet we still apply this definition to is ourselves (aren't we special). Be your ancestors short, gracile San bushman from South Africa superbly adapted for life in the Kalahari, one of the central African tribes whose red blood cells have evolved clear down at the molecular level to make you genetically immune to malaria, or two meter tall Nordics whose skin and hair have lost almost all pigmentation allowing their bodies to utilize the very limited available sunlight in the far north to process vitamin D to keep them alive... you my friend are
Homo sapiens because all matings between all humans on the planet produce viable offspring. If we applied this definition to fishes, for example, there would only be a Baensch Atlas I and we would all save some money. We are able to use a different definition for the rest of life because making an argument that
Panaque maccus is "better" than
P. cochliodon is just plain silly, while making the argument that race X is "better" than race Y has pretty much been the history of organized human violence.
One recent study I read pointed out that upon completing DNA testing of 14 species of Lake Victorian c i c h l i d from 9 different genera (different genera!) there was less genetic difference between them than between a typical population of humans. That pretty much means that a very small town in Iowa has more genetic diversity among its population of
H. sapiens than several hundred c i c h l d s described as distinct species and belonging to over a dozen genera.
The important thing to remember, from a hobbyist's point of view, is that there is currently no universally agreed on definition of a "species" and that the definitions out there range far and wide. In fact several scientists are now arguing that it is time to just throw out the entire concept of "species" (won't that make Jool's and Mats' managing of the Cat-eLog less time consuming!) as it is based on faulty underpinnings. The species concept came about at a time when scientists believed, as the religious texts stated, that every organism was present in its final form as made by the Creator. All we had to do was find them all (as Noah did) and catalog them... that is why we are able to choose a single specimen from a population, called a holotype, to represent an entire species. Linnaeus wrote Systema Naturae in 1735 and gave us Taxonomy
135 years before Darwin wrote On the Origin of Spp and gave us evolution. Then we realized that evolution was in fact an ongoing process. However, we were still ok as we adopted the idea that evolutionary change takes place over very, very long periods of time.
Now we know this is not true at all. 12,000 years ago Lake Victoria was dry. Those 500 species of c i c h l i d s did not come about after millions of years of evolution, but rather after a few thousand. To bring the point home to
H. sapiens; a recent study of black Americans showed that only 8% still retain the genetic immunity to malaria. Once the evolutionary pressure for immunity to malaria was removed the population dropped the adaptation not in 1,000s of years... but in a dozen or so generations.
So, the argument goes, it makes no sense to attach a static "species" name to what we know are constantly evolving gene pools. In fact, a species described in 1809 may not even be valid today if it has changed sufficiently in the last 200 years.
-Shane
"My journey is at an end and the tale is told. The reader who has followed so faithfully and so far, they have the right to ask, what do I bring back? It can be summed up in three words. Concentrate upon Uganda."
Winston Churchill, My African Journey
So, if L236 is 'always' (?) found together with L333 as you say, are they fewer and far between than L333 in the same area, or are their numbers approximately the same? 
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