Implications for a Southeastern US Eco Sample Clauses

Implications for a Southeastern US Eco. Region Overall, raccoons do share similar patterns of subdivision as do other unrelated taxa within the southeastern US eco-region based on the mitochondrial data although nuclear data fail to support Florida as a biologically distinct entity. This pattern is reflective of a historical, temporary vicariance event (gathered from mitochondrial DNA) and ongoing contemporary gene flow (based on microsatellites). As noted above, raccoons from the Florida peninsula are mitochondrially distinct from other areas along the eastern seaboard, with the division occurring roughly along the same line in Florida as has been documented for short-tailed shrews (Benedict et al. 2006). This line falls within the proposed Northern Florida Suture-Zone (Remington 1968), lending evidence to a common phylogeographic boundary for multiple species in the southeastern US eco-region. In fact, Remington (1968) previously included the raccoon on his list of more than 50 possible hybridizing species in the suture-zone. An isolating mechanism during the moderate to high sea stands of the Pleistocene may be responsible for the mitochondrial differentiation in Florida raccoons. During this time, Florida was described as a series of small islands separated by water (Remington 1968) during interglacial periods. In particular, the St. Xxxxx River in northern Florida functioned as an extension of the Atlantic Ocean and may have acted in a similar fashion as the much older Suwannee Strait. Furthermore, Swift et al. (1986) noted that peninsular Florida south of the Suwanee and St. Xxxxx drainages served as a distinct faunal province for fish, lending additional evidence to an isolating mechanism in that particular area. It is unlikely that Florida raccoons underwent any bottlenecks or founder effects given the high amount of haplotype diversity present in the population whether analyzed as part of a larger southeastern group or alone.