Interpreting the Paleozoogeography and Sea Level History of Thermally Anomalous Marine Terrace Faunas: A Case Study from the Last Interglacial Complex of San Clemente Island, California

Narrow water barriers prevent multiple colonizations and limit gene flow among California Channel Island wild buckwheats (Eriogonum: Polygonaceae)

“…Using late Quaternary uplift rates (Muhs et al, 2012;Muhs, Groves & Schumann, 2014) and the highest elevations of the modern islands, the highest parts of San Clemente Island could have emerged as long ago as 3.0 Ma, whereas San Nicolas Island might have only emerged as recently as~1.2 Ma. Using late Quaternary uplift rates (Muhs et al, 2012;Muhs, Groves & Schumann, 2014) and the highest elevations of the modern islands, the highest parts of San Clemente Island could have emerged as long ago as 3.0 Ma, whereas San Nicolas Island might have only emerged as recently as~1.2 Ma.…”

“…Colonization of the California Channel Islands has been relatively recent, geologically speaking, because the modern islands formed by relatively slow uplift during the late Tertiary and Quaternary. Using late Quaternary uplift rates (Muhs et al, 2012;Muhs, Groves & Schumann, 2014) and the highest elevations of the modern islands, the highest parts of San Clemente Island could have emerged as long ago as 3.0 Ma, whereas San Nicolas Island might have only emerged as recently as~1.2 Ma. With low late Quaternary uplift rates on the northern Channel Islands (Pinter et al, 1998), the highest parts of Santa Cruz Island and Santa Rosa Island might have emerged considerably prior to~3.0 Ma.…”

Late Quaternary sea-level history and the antiquity of mammoths (Mammuthus exilisandMammuthus columbi), Channel Islands National Park, California, USA

“…No attempt is made to discuss the pros and cons of the human vs. climate change causes for megafaunal extinction in North America, but some of the findings presented here have relevance to the debate on these two causes for mammoth extinction specifically on the Channel Islands. Kanakoff and Emerson (1959); Valentine (1962);Orr (1960); Vedder and Norris (1963); Addicott (1964); Lipps et al (1968); Kern (1977); Kennedy et al (1982Kennedy et al ( , 1992; Muhs et al (1992Muhs et al ( , 2002aMuhs et al ( , 2010Muhs et al ( , 2012Muhs et al ( , 2014aMuhs et al ( , 2014b; Heusser (1995Heusser ( , 2000; Kennett and Venz (1995), and Grant et al (1999 There is little question that early humans in North America hunted proboscideans. Indeed, Mammuthus and Mammut are two of the very few megafaunal taxa for which there is unequivocal archeological evidence indicating human predation, and there are at least a dozen such sites with mammoth remains in North America (see compilations in Meltzer, 2002, 2003).…”

Little Islands Recording Global Events: Late Quaternary Sea Level History and Paleozoogeography of Santa Barbara and Anacapa Islands, Channel Islands National Park, California

“…Given the overall low uplift rates reported for many of the other California Channel Islands (Muhs et al 2012(Muhs et al , 2014a, it is hypothesized that low-elevation terraces on SBI, ANA, and Santa Cruz Island likely date to some part of the LIG complex, MIS 5. It is further hypothesized that given the previous studies showing a complex history of MIS 5.5, 5.3, and 5.1 (equivalent to MIS 5e, 5c, and 5a, respectively, of Shackleton and Opdyke 1973) as seen in the marine terrace record elsewhere on the California coast (Muhs et al 2002a(Muhs et al , 2012(Muhs et al , 2014a(Muhs et al , 2014b, there could be a similarly complex history recorded in the terraces and their fossils on these small islands. To test these hypotheses in the present effort, field and laboratory studies were conducted, including terrace mapping and elevation measurements, geochronology of fossils from the terraces, and paleontology and paleozoogeography of the fossil assemblages.…”

“…For the study areas considered here, these would be species that now live well to the north or south of Santa Barbara Island (SBI) and Anacapa Island (ANA). Extralimital species of mollusks and corals, indicating warmer SST during MIS 5.5, have been documented in the Indian Ocean along the western coast of Australia (Kendrick et al 1991), around New Zealand and the southern coast of Australia (Murray-Wallace et al 2000), along the Bering Sea and Arctic Ocean coasts of Alaska (Brigham-Grette and Hopkins 1995), in the eastern Atlantic Ocean and Mediterranean (Meco et al 2002, Muhs et al 2014c, in the Pacific Ocean along the shores of Oahu in the Hawaiian Islands (Kosuge 1969, Muhs et al 2002b), along the central and southern California coast (Kennedy 2000, Muhs et al 2002a, 2014a, 2014b, and in Baja California (Lindberg et al 1980, Emerson et al 1981. Thus, the importance of thermal expansion during the LIG may have been greater than the studies of Turney and Jones (2010) and McKay et al (2011) imply.…”