Taxonomy and the rule of eight

August 14, 2014 | By DAMIEN SCHIFF

Earlier this year, the Foundation filed a petition on behalf of property rights and building industry groups to challenge the continued listing of the coastal California gnatcatcher under the Endangered Species Act.  The nub of the petition is that new scientific studies—including a mitochondrial DNA and nuclear DNA analysis by Dr. Robert Zink of the University of Minnesota—definitively demonstrate that the gnatcatcher does not constitute its own subspecies but rather is the same bird as its plentiful gnatcatcher cousins in Baja California.

The petition garnered some criticism from the scientific community, with one bird expert stating that the latest nuclear DNA study, in addressing only eight genetic markers of the gnatcatcher, was based on an inadequate data set.

Yet the Service appears to agree with the Foundation that, at least in some circumstances, Dr. Zink’s approach is sufficient.  For example, this week the Service published a determination not to list the Warton’s Cave Meshweaver—an eyeless spider—because the arachnid was not a separate species or subspecies; and, the data the agency relied on included a nuclear DNA study based on eight genetic markers.  So, at least for spiders (and we hope for gnatcatchers), eight is enough.