It is not only what we have inherited from our fathers that exists again in us, but all sorts of old dead ideas and all kinds of old dead beliefs and things of that kind. They are not actually alive in us; but they are dormant all the same, and we can never be rid of them. Whenever I pick up a newspaper and read it, I fancy I see ghosts creeping between the lines. There must be ghosts all over the world.
—Henrik Ibsen, Ghosts
(Continued from the previous page)
For many, an evolutionary theory is an explanation of the origin of "species." But, in fact, the definition of species has long been in dispute. It is a vague and ambiguous word — a fact that most biologists would readily admit. The ultimate purpose of this discussion is to make certain claims about the nature of the evolutionary process. I am convinced, however, that it would be very unwise, in beginning such a project, to pass over the fact that species is, in fact, an ill-defined entity. How can we expect to construct a clear explanation of the evolutionary process if a key element in our account has no clear meaning?
This first section, then, will focus on the history, meaning, and usage of species. It will not gloss over, as do many works on evolutionary theory, the problems associated with this word. Such a discussion is presented here, not only to explain the fact that stabilization theory makes far less use of the word species than does conventional theory, but also to make some important points about the nature of evolutionary debate. In particular, this first section will look closely at this word because any clear argument, of any sort, must define its terms. Ultimately, the exact ways in which species is used within the context of stabilization theory will be stipulated, which are quite limited in comparison with normal practice under conventional theory. But, before that point can be reached, a good bit of explanation will be needed to show why such restrictions are necessary. NEXT PAGE >>
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