HIGH-RESOLUTION RECORDS OF GROWTH TEMPERATURE AND LIFE HISTORY OF TWO NACELLA LIMPET SPECIES, TIERRA DEL FUEGO, ARGENTINA

Nacella deaurata (Gmelin, 1791) and N. magellanica (Gmelin, 1791) are common intertidal species of patelloid limpets found along the coast of Tierra del Fuego, Argentina. Stable isotope ratios in patelloid limpets have been previously established as proxies for coastal environmental change at sub-monthly resolution. Proxy records of paleoenvironmental change at high, southerly latitudes are largely interpreted through ice, marine, and lake cores, which, while temporally extensive, fail to capture high-resolution variability in coastal environments. Hence, a proxy record that shows sub-monthly resolution is necessary to understand seasonal variability in coastal environments from high southerly latitudes. Here, we examine δ18Oshell and δ13Cshell values of modern specimens of N. deaurata and N. magellanica to test the hypotheses that: 1) Nacella spp. form their shells in isotopic equilibrium with ambient water; 2) Nacella spp. record variation in SST through oxygen isotope ratios; and 3) Prominent growth lines in Nacella spp. form annually.Master of Scienc