We might more appropriately look to civil l aw in

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: tems, also operating in a complex and murky w orld, in which decisions are reached on a preponderance of M A DAG A SC A R CO NSERVAT I O N & D E V ELO PM EN T VOLUME 8 | I SSUE 1 — J ULY 2013 t he evidence. Still, we have to be careful with our metaphors; a nd the familiar criterion of ‘beyond reasonable doubt’ used in c riminal cases may be a little too stringent for some real - world b iological data sets. We might more appropriately look to civil l aw, in which more general probabilities apply. Much as tidyminded systematists might wish they were not, very closely related species are often genetically leaky vessels, which means t hat reasonable doubt as to individuation can in some cases be v ery difficult to banish. As a systematist, I would instinctively p refer in those cases to apply the presumption of innocence, a nd to regard sister populations as conspecific unless there a re compelling reasons to conclude otherwise. But it is also a pparent that from a conservation standpoint the evidence m ight be interpreted differently, particularly where distinctive a nd highly localized populations are imperfectly known; and c learly, in an arena as complex and nuanced as this, a ‘one size f its all’ solution is never going to apply. As in the law, a judicious c ase - by - case approach is indicated. Still, the reasons for adopting a restrained general attitude t oward species recognition are compelling; and they relate not s imply to the multifaceted nature of species as reflected in t he plethora of definitions available, but to the nature of the e volutionary process that produced the diversity we see in M adagascar today. For there is every reason to believe that, far f rom being some kind of passive relict that in isolation long ago e stablished an equilibrium with its environment, the Malagasy b iota is, instead, in a dynamic state of evolutionary flux (cf. c ontributions in Goodman and Benstead 2003). This is perhaps m ore than ever the case since the recent elimination of the i sland’s megafauna. Above the level of the genome, the fixation of heritable n ovelties in local populations belonging to existing species is t he most fundamental process involved in generating biodiversity. This process is synonymous with the formation of those d iagnosable variants we call subspecies. And it is an essential p art of the evolutionary dynamic. To promote all subspecies to s pecies simply on the grounds that they are diagnosable is to r ob the Malagasy fauna of the very mechanism that we know m ust have operated to produce the island’s famous diversity at l ow taxonomic levels. C ONSERVATION AND SPECIES. S o, what does all this imply for c onservation? People concerned with protecting the w hole environment at particular places on the planet’s surface – w hich, captive propagation of individual species aside, is all t hat can be effectively done in this arena – often get rather i mpatient at what they see as the quibbling of taxon...
View Full Document

Ask a homework question - tutors are online