Surprise Birth

[ConcinusMan]

But this is coming from a person who questions the validity of species, let alone subspecies. What you're suggesting would make all (30 something) thamnophis the same species. Radix, ordinoides, and sirtalis would be subspecies. That leaves no catagory left to distinguish between infernalis and concinnus, or any other sirtalis.

Now, only one thing left to consider. How the heck are we going to know what snake we are talking about when one person has a T.s. infernalis, the other a T.s. pickeringii? Obviously, they aren't exactly the same morphologically or geographically, so what to do about that?

Personally, I don't think that the TRUE relationships between the different thamnophis snakes will ever be known fully until all have been DNA sampled and the data analyzed. If that was done, it wouldn't surprise me one bit to find out that some sirtalis subspecies are more closely related to non-sirtalis Thamnophis snakes than they are to each other. Afterall, even though it doesn't appear so, chimps are more closely related to humans than they are to orangutans or monkeys. Until the DNA results are in (might never happen) we have Thamnophis (genus) sirtalis (species) and so, we must further categorize by use of subspecies.

Personally, I tend to think that T.s. infernalis and T.s concinnus are the same species. No more different from each other than a black person is from an blond-haired, blue eyed, fair skinned Irishman. Like humans, the differences between the two happen in gradients over distance. I guess that's what makes it so difficult for me to call offspring of the two snakes a hybrid.

[Stefan-A]

But this is coming from a person who questions the validity of species, let alone subspecies. What you're suggesting would make all (30 something) thamnophis the same species. Radix, ordinoides, and sirtalis would be subspecies. That leaves no catagory left to distinguish between infernalis and concinnus, or any other sirtalis.

Nope, different labels apply. They are all the same genus, Thamnophis. All species belonging to that genus share a slightly less recent common ancestor and that genus shares a slightly more distant ancestor with the rest of Colubridae. And so on and so on. Let's not forget that the linnean system was thought up long before Darwin came along and now people are bending over backwards to apply the system to a situation that's constantly changing, instead of the static one Linnaeus expected. For taking snapshots of the current situation, it's good enough, but a system that describes the actual relationships between units, should be able to go back 4 billion years without problems and work from here "to the end of time", taking into consideration the fact that lines are diverging and will eventually give rise to the equivalent of new subspecies and eventually full species, genera, families, orders etc. Provided they don't become extinct as most, if not all of them actually will.

There are several species concepts. I don't know if this will make it better or worse, but here's a link:
Species - Wikipedia, the free encyclopedia