Say what you will about wikipedia, but here’s what I was referring to:
I should have added that subspecies are generally expected to hybridize, although not regularly. If they never hybridize, then it would make sense to just call them 2 species.
It’s also my understanding that clinal variations are not accepted as grounds for establishing subspecies, for the obvious reason that there is no clear place to draw the line.
So, are the subspecies in the ring species really just clinal, or are they distinct populations that, from time to time, hybridize?
Strictly speaking, subspecies are entirely subjective (much moreso than are species, for example), so there really aren’t any definitive rules for deciding when a population represents a subspecies and when it might be considered any other subspecific category. In contrast with Wikipedia’s definition, this Stanford University page defines subspecies as follows:
Since you mentioned Wikipedia, here’s what it says regarding clines and ring species:
Now, despite Wikipedia’s mention that “populations elsewhere along the cline interbreed with their geographically adjacent populations as in a standard cline”, and that “a well-marked cline does not allow for a delineation of subspecies”, many such intermediate populations are, in fact, given subspecies designations. For example, here’s what UC Berkeley’s Evolution For Teachers website has to say about ring species:
(bolding mine; also, note that, technically, the names given should really be written as E. e. klauberi and E. e. eschscholtzii, since these are subspecies of Ensatina eschscholtzii)
And, of course, another often-used example of ring species, the herring gull, is typically divided into subspecies along its range, as well (and separate species, as well).
As one can see, subspecies are neither easily defined nor identified, and there is almost always controversy regarding whether a given subspecies should, in fact, be considered as such. They work as convenient labels for discussing certain populations, but not so well as discrete entities. Such is the nature of ranked taxonomic systems…
Ring species are one element that shows the difficulty of the species concept. In theory, it is fine, but in practice, biology does not play in neat categories. Differentiation of species is a complicated mess that only loosly fits rules.
But you are correct that full speciation has not occurred.
Napier said:
You are equating to different uses of the word “better”. That’s called equivocation, and is a fallacy of logic.
Trying to be a better person means self improvement, being more moral, living up to some set of standards of behavior. That is different than measuring by ability to perform (strength, intelligence, etc).
Shmendrik said:
No he didn’t he just said it awkwardly. What he meant was test takers now effectively get 70 to 100 bonus points on their score. Ergo, if they got a 490 and you got a 490 back in 1982, it’s as if they really scored a 400. They aren’t as smart as they are getting credit for. TriPolar said:
Not really. Species is a useful concept that’s blurred around the edges.
I’m not sure if that was meant as a cite to back up the claim you made up-thread, but it doesn’t.
At any rate, as some have mentioned about the term “species”, it’s clearly a human construct that we have overlaid onto a natural world that often doesn’t divide itself up neatly into self-contained boxes. So any definition we use is just that-- a definition. Best to keep in mind that there are always going to be exceptions and populations that don’t fit any given definition.
As for sub-species, it can be useful to use that term to distinguish populations, but there isn’t some overseeing body to put its stamp of approval on any particular scheme of labeling subspecies.
First he said that they raised the test scores because more students from less rigorous schools are taking the test. Then he said that we are “100 points stupider, as a nation.” No, we’re not. The population taking the test may be stupider, but as he just said, that’s because there are more students from crappier schools taking the test.
I don’t specifically mean “better” in two different ways. “Trying to be a better person” could imply moral standards, but could also imply learning new skills, improving health, or other things. To equate “trying to be a better person” with “self improvement” is an empty tautology. We can’t try to improve our genetics or the circumstances of our birth and early origins, but in hoping our kids turn out well we can hope for these things.
What I’m getting at is that we reject the idea of superior and inferior humans because it is politically incorrect. And that’s understandable, because various political and social movements of the past hijacked ideas about superiority and inferiority to justify genocide, pogroms, holocausts, slavery, Jim Crow laws, wars, and a litany of other evils. I think the problem is some kind of human propensity to warp thought to serve vicious power agendas. Maybe the best practical solution is to pretend we are all equally “good”, and certainly it is almost an empty discussion without trying to break “superior” and “inferior” into multidimensional detail. But it is surely inaccurate to imagine that “better” and “worse”, which can apply to practically every kind of thing there is, have no application to ourselves.
Fine, but in your anecdote you’re still leading the other person.
“Do you think some people are better than others?” has certain implications, as evidenced in phrases like “Do you you think you’re better than me?!”.
If you were to ask “Do you think some people act better than others?” the answer would be yes, and the apparent hypocrisy disappears.
Few people actually argue that. Sure there are some people that subscribe to a philosophy that everyone’s talents balance out, and that we’re all equally “good”, but I think such people are the minority.
Generally, when people say “Everybody’s equal” they mean we’re all equally important, or should be treated equally. We’re aware that some people have a better set of genes than others.
Even something like “We’ve all got something to contribute” doesn’t mean we believe our possible contributions are equal.
Even allowing for some people being more talented (for want of a better word) than others, we’d still have to choose how to measure that. In nature, you could think of “better” as whoever reproduces most successfully.
To us, it could be anything, or any permutation of anythings.
That is two different uses of the word “better”. The difference in response is precisely because the meaning of the word is different in each case.
You’ve set up a strawman with your equivocation. If your intent was to point out why the second use is different and so the response is different, you’ve done a poor job of making that clear. You’ve focused the argument on “why does a person say they want to be a better person but then disagree that there are such things as better people?” rather than on some other argument.
You have a point about power agendas. There may be superior and inferior people, but that doesn’t mean that division breaks down on ethnic, gender, religious, genetic, national, or any other similar set of lines. But those are the lines that people most easily see and try to break the distinction down along. Before you can establish if there can be superior or inferior humans, you first have to establish the system of measurement, the criteria by which they are being evaluated. Only then can “superior” and “inferior”, or “better” and “worse”, have any meaning.
There’s very low genetic variation among Homo sapiens, especially in populations outside of africa.
The leading explanation for this is generally that only a subset of population types migrated from africa, and indeed that the human population within africa was small to begin with.
Having trouble finding a site that spells this out clearly though. According to this paper, total human genetic diversity is comparable to that of a single (large) chimpanzee population.
