On Salamanders (again)

What is natural? Where should we looked for the telos of a thing - and how should we value it?

Why should we care? Why do I care? Because I've just I've just been gobsmacked by a preposterous assertion about "genetic purity".

Are you sitting comfortably? Yes? Then I'll begin.

According to this story, it seems that the native California tiger salamander (an endangered and protected species in the US) has been interbreeding with introduced Texan tiger salamanders (tsk! tsk!). Unexpectedly though, the offspring seem to show "hybrid vigour", a characteristic more typical of plant hybrids. Technically, a hybrid is the offspring of parents of different species, and to have vigour means in this context that the organism survives not just well, but better than either of its progenitors (and by survives better I mean surviving and having more offspring - it's no good just lasting forever if you don't breed, evolutionarily speaking).

Where hybrid vigour arises, one may therefore expect the hybrid to displace both progenitors, unless (remember the important "on average" - which can be defined in terms of population extent, environmental range, niche qualities etc.) the progenitors nonetheless survive better than their hybrid offspring in particular environments.

Picture: Three types of salamander larvae: native California tiger salamanders (Ambystoma californiense), barred tiger salamanders (Ambystoma tigrinum mavortium), and the hybrid offspring born when the two species mated. (Credit: Bruce Delgado, U.S. Bureau of Land Management) [Used without permission]


And?


Apparently this "raises difficult questions" because whilst some might say that hybrids should be tolerated since "they are favored [sic] by natural selection, and 'improve' the original species", some others - this is the good bit - "might consider hybrids to be genetically impure and regard them as threats to the native salamanders, their competitors and their prey."

How on earth could the hybrids be genetically impure? They are not Californian tiger salamanders, nor are they Texan tiger salamanders - they are what they are. They are pure salamander. Yes, they are different to both progenitors but what is the justification for choosing either to be the standard for "tiger salamanderness" against which the newcomer should be assessed?

The issue implies some sort of telos for which we should have due regard, in much the same way as opponents of genetic "engineering" might object to the modification of pigs (for example as sources of tissue for xenotransplants) for destroying the "pigness" of the pigs concerned.

Whilst I don't intend to debate the philosophical status or significance of telos at any great length ("great" clearly being a relative term), the question nonetheless has to be asked: where or how could telos have its origin? Before sperm and egg combine, they might be considered to have their own telos, but once the egg has been fertilised both lose their separate identity. Where does the telos go, or how is it transformed - and if it can be transformed or vanish naturally, what limitation should we impose upon ourselves with respect to any alteration we might wish to make?

Many might claim (thank god this isn't academic and I don't have to supply citations to support such assertions!) that God - particularly, and hence the initial capital, the deity of one of the monotheistic religions such as Christianity, Judais, and Islam) - takes care of telos, its origination and continuation. But take any such idea too literally and we would be unable to breed animals or plants using even the old-fashioned methods; we would instead have to content ourselves with whatever offspring occurred by chance (and I'll skate over the difficulty of what to do with a particularly nice - but entirely natural - strain of wheat, for example, that just catches your eye... should you favour its seeds over those of its less appealing neighbours when you plant your next crop?).

Whatever claims might actually be made, sooner or later one must stand upon the edge of Ginnunga Gap between the icy purity of deontological ethics and the industrial heat of pragmatism, utilitarianism, etc. - and just stare across: there is no pleasant balmy island in between. If one adheres to the idea that God decides the way things are, then no mortal idea of harm or benefit can affect the status quo.

Or can it? God has traditionally given human beings Free Will (by which I mean that various traditions claim this for their deity, rather than the interesting (but not very useful idea) that God has traditions, and that one of them is to give human beings Free Will whenever he creates them) and free will implies choice.

The real question is how we exercise that choice - and in particular the criteria to be used in weighing our choices.

I cannot see that we can value one species higher than another a priori. We can - and should, I suggest - value diversity above homogeneity, and for that reason (trying to bring this post to a end without boring the pants of everyone - including myself) we should be delighted at the emergence of these hybrid salamanders and we should endeavour to preserve the native Californian tiger salamanders as a distinct species.

If the two objectives are in conflict in California, then as long as both Californian and Texan salamanders exist elsewhere (and continue to be able to interbreed!) we could perhaps consider the extermination of the xeno-salamanders. We would lose the prospect of further delights arising from the development of the hybrids (unless we put them somewhere else, or breed them in captivity, or...) but whereas, given the criteria specified, we can have them back at any time, unless we can reverse engineer the Californian salamander and resurrect it should it die out, as things stand once they're gone they're gone and it would seem better to try to protect them now.

Salamanders are also interesting for some very non philosophical reasons, mostly to do with their folklore: they were supposed to be immune to fire... but do you really want to hear about that too?