Edisto Island Fossil Vertebrates 
3 
paleoclimatic implications of the fauna; and (3) discuss the significance of 
the fauna in relation to other southeastern Pleistocene localities. 
GEOGRAPHIC AND GEOLOGICAL SETTING 
Edisto Island is a barrier island located 34 kilometers (21 miles) 
southwest of Charleston, South Carolina, at longitude 80°17’W and 
latitude 30°31’N (Fig. 2). Fossils are found in the intertidal zone along 
the beaches, along stream banks and estuaries, and occasionally are en- 
trapped in fishing nets. The fossil material is typically well mineralized 
and black in color. 
The fossils have not yet been found in situ and the fossiliferous 
stratum (or strata) has not been identified. There are, however, several 
possible source areas: (1) Holocene sediments on or near the beach, (2) 
the Silver Bluff formation of latest Pleistocene age which, according to 
Colquhoun (1969), lies immediately inland of the Holocene sediments, or 
(3) earlier Pleistocene strata which underlie the previously mentioned 
units and crop out offshore below sea level or in estuaries and streams. 
The fossils may be derived from any one or all of these units. 
Although often reported from Jeremy Inlet and Edingville Beach, 
the fossils are found also at Botany Bay Island, Edisto Beach, and the 
southern tip of the island (Fig. 2). This widespread occurrence suggests 
that the depositional area was equally broad or that, once eroded, fossils 
are easily transported by currents to the widely separated points of 
discovery. 
The large number of terrestrial species present in the Edisto Island 
fauna and the probability of an offshore source area suggest that sea level 
at the time of deposition was lower than the present level. Sea level fluc- 
tuated during the Pleistocene and Holocene, in response to alternating 
glacial and interglacial stages (Cazeau et al. 1964; Hoyt 1967; Whitmore 
et al. 1967; Winkler and Howard 1977). Webb (1974) related these fluc- 
tuations of sea level to the North America mammal ages and glacial 
stages within the Pleistocene (Fig. 1). 
With substantially lowered sea level during Pleistocene glacial 
stages, what is now Edisto Island would have been a nearshore but inland 
area possibly exhibiting a savannahlike terrain; the deposition on Edisto 
Island was probably alluvial. Numerous Pleistocene streams and es- 
tuaries might have cut into underlying Pliocene and/or Miocene strata, 
deposited the Pleistocene vertebrate fossils, and possibly caused some 
mixing. Although evidence is not conclusive, the widespread recovery of 
fossil vertebrates along the southern Atlantic coast (Frey et al. 1975) 
suggests that the fossiliferous unit or units is extensive regionally. At 
Edisto Island, this unit probably crops out both in streams and estuaries 
on the island and in nearby offshore areas. 
