Species

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354 Species

“loveliness” of competing hypotheses. But while pattern recognition involves prior
knowledge—of the domain and its general properties, mostly what to look for—
it does not involve assessing the loveliness of hypotheses. Instead it involves assess-
ing the salience of differing stimuli. In order to make an IBE, you have to recognize
things. For example, to make an IBE about what made footprints in the snow, you
have to recognize the pattern of footprints. This is something you have learned to do,
not least by making footprints. Second, to make an IBE that a deer made these par-
ticular tracks, you need to recognize the difference between bipedal and quadrupedal
tracks (gotten from years of observing them), and between claws and hoofs (likewise)
and so on. With all that categorical apparatus in play, you “leap” to the hypothesis
that of the likely animals in the area, it was a deer, not a cat or horse.
Classification differs, at least when the DUI is unexplored. You know about the
wider domains in which the DUI is situated, so you are primed to see some sorts of
things, but you get an idea of what is in the DUI by looking, a lot. Experience trains
you to see patterns, and then and only then can you make IBEs. Hence the argu-
ment above. There are those who think taxa are explanations; for example, Fitzhugh
thinks species are explanations.^48 An explanation of why a species is a species is
something independent of recognizing the species. Others have argued that phylog-
enies are explanations or hypotheses, in a Popperian fashion. In the case of phylog-
enies, the explanation is the theory of common descent (or, in some cases, lateral
transfer and introgression through hybridization), but the phylogenies themselves are
patterns in data. If a systematist works out the phylogeny of a group, then there is an
IBE of common ancestry, but common ancestry is not the same thing as working out
the phylogeny.^49 The relations of different kinds of cognitive activities here are not
simple. While it may help to classify them as distinct activities, in practice we shift
and change from one to another, or do them simultaneously. Science is not done by
recipe. However, it pays to be clear about the differences.


What Kind of Phenomena Are Species?


Assuming species are phenomena, we must ask what kind of phenomena they are.
A particular morph of a species, such as a regional plumage in a bird, or a gender
morph, is not a species; all specialists would agree with that. So, even if species are
phenomena, not all biological phenomena are species. We need to know when a phe-
nomenon of clustering traits is a species in order to have something to explain. How
do we arrive at this?

(^48) Fitzhugh 2005, 2009. I must disagree here. That some phenomenon is a species is a hypothesis,
assuming a particular conception of what species are for that group, and it is defeasible, but calling
something a species is not an explanation of that phenomenon per se.
(^49) A comment about cladistics that was made very early on is that common ancestry and phylogenies
are different. The pattern cladists, so-called, forcefully made that point to the stage that their crit-
ics accused them of creationism and “typological thinking.” However, once we recast the issue as
explicandum and explanandum, much of the heat goes out of this debate. Even process cladists now
concede that common ancestry, while it may be the cause of phylogenetic patterns, is a hypothesis in
each individual case that may be confounded by parallelism or lateral inheritance, for instance.

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