>>i was thinking, how we group animals. u got ur genus then ur species then a subspecies. but is there any middle ground in there? like can there be a species with many different morphs and hybirds and different patterns, yet they are all simply the same species?

Yes. There are lots of different breeds of dogs and chickens but all breeds of dogs are the same species and all varieties of chickens are also the same species.

> i dont think we can group animals that easily. ill use s few examples.

As a matter of fact, it is not easy to classify animals. Plants are also difficult to classify, may be more so because many plants can freely hybridize with each other.

>look at the eastern racer, with the subspeacies northern black racer and southern black racer. they are like the same thing.

Looks are often deceiving. Many milk snakes look similar to mountain kingsnakes, but milk snakes and mountain kingsnakes are different species.

> and look at an eastern milk snake and a pueblan milk snake. they are the smae species but look way different.

Yes they do. The gray banded kingsnake is another good example of a variable species.

> so in other words a northern black racer is to a southern black racer as an eastern milk is to a pueblan milk. but there seems to be way closer of a connection to racer subspecies and milk snake sub species. so is separating and grouping animals really that simple and clear cut?

No, it is not. Even scientists often disagree as to what a species is. And they often disagree on whether two populations are the same species or different. Most biologists, however, agree that if two populations are reproductively isolated from one another, then they are not the same species.

>like can there be a population thats 2/3rds one thing and 1/3rd another? or can u have a population evolve in such a way that it eventually becomes its own subspecies?

All biological organisms have to be adapted to their local environments. Sometimes these adaptations will cause changes in morphology. For example, the Lampropeltis zonata herrerae living on a desert island has to adapt to this atypical habitat. One of the adaptations that herrerae has made is to have reduced red markings. L. z. herrerae is therefore often classified as a different subspecies because it simply looks different. To some biologists though, the mere fact that it looks different and the fact that it is stranded on an island means that it will be unable to share its genes with other populations of L. zonata. To these biologists, it is sufficient evidence that L. z. herrerae is a different species. Other biologists disagree because they do not consider geographic isolation a valid criterion for recognizing new speces, because otherwise populations of the same species on different sides of the same river would be classifiable as different species. They also point out that if one looks close enough, then one can find at least one difference between two populations on opposite sides of a geographic area. Therefore herrerae should not be recognized as a different species.

Disagreements like these are quite common nowadays, as different schools of taxonomists have embraced different definitions of species that are mutually incompatible. BTW, it is possible for different individuals of the same species living in the same area to evolve into a different species. Geographic isolation is not necessary. The Cichlid fishes found in some African great lakes are a good example. Biochemical data shows that many different species living in the same lake originally were descended from the same ancestral species. And yet competition among individuals of the same species is so intense that it provides a strong selective advantage to some of the individuals of the ancestral species to adapt to a different ecological niche (which in this case primarily involves different food sources). Therefore those who suggest that geographically isolated populations will inevitably evolve into different species are simply mistaken. Geographic isolation is not even necessary for speciation to occur. Hence geographic isolation should not be used as a criterion for naming new species.

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