Giraffe genes and species

Monday, September 19, 2016
by Cameron Shelley

A Wired article gives an account of some research on the matter of how many species of giraffes there are.  Up until now, biologists held that there exists one species, Giraffa camelopardalis, divided into nine subspecies.

Research led by Julian Fennessy, of the Giraffe Conservation Foundation based in Namibia, suggests that there are actually four different species:  northern, southern, reticulated, and Masai.  This conclusion was based on genetic analysis of skin biopsies obtained from animals around Africa.

This research illustrates how the species concept is somewhat fluid.  In the past, researchers distinguished species by their bodily form, behavior, and habitat.  Technology that permits ready and inexpensive genetic analysis has boosted the role of genetic difference to this issue as well.

Work like this may have political consequences.  Laws that protect threatened species may come to apply to one "new" species of giraffe even though the entire giraffe population may be robust.  Since the "new" species seem to be located in specific regions, e.g., "southern", the burden of protecting them may fall on one or two governments.

Whether that improves or decreases the giraffe's chances of survival depends on the specifics of that situation.

The work may also tend to reinforce notions of genetic essentialism, which refers to the tendency to see genes as providing answers to broad questions about the nature of things.  Where human beings are concerned, the matter of putting people into groups according to their genetic differences is a notoriously fraught matter.

So, it is interesting to note that biologists differ over the extent to which genetic differences, as such, contribute to the matter of dividing animals into species:

The new proposed giraffe taxonomy is one group’s interpretation of the genetic record, but it’s not the final say. DNA analysis is a tool—not an oracle.