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A cave-monitoring study in Hatchet Bay Cave on the island of Eleuthera, Bahamas, has examined the origins of variations in oxygen and carbon isotopic and minor element composition in cave calcites. Every 3 to 8 months, between 2012 and 2016, temperature, humidity, cave air (δ 13 C CO2 ), dripwaters (δ 18 O and δ 2 H values, and Ca, Sr, and Mg concentrations), and the chemical composition of precipitating calcite (δ 18 O and δ 13 C values, and Ca, Sr, and Mg concentrations) were analyzed in two rooms in the cave. Results from the elemental analyses show that throughout the cave prior calcite precipitation was a driver of the elemental chemistry of the precipitated calcites. In addition, cave calcites show that δ 13 C and δ 18 O values were positively correlated with Mg/Ca ratios. The Mg/Ca ratios were also positively correlated with lower calcite precipitation rates. Therefore, water/rock interactions may also influence δ 13 C and δ 18 O values and Mg/Ca ratios of the calcite. Differences were observed between the two rooms, with the Main Room of the cave exhibiting increased prior calcite precipitation, more ventilation, lower calcite precipitation rates, and δ 18 O values, which were farther from equilibrium when compared to the more isolated portion of the cave. These results also validated previous interpretations from Pleistocene stalagmites collected from a nearby Bahamian cave suggesting that a positive covariation between Mg/Ca and δ 13 C values reflects water/rock interactions.

Cirolana troglexuma Botosaneanu & Iliffe, 1997 is redescribed and a Lucayalana Bruce & Brix, gen. n. established for the species. In total 38 specimens were collected from Hatchet Bay Cave, Eleuthera. Specimens on which previous records of L. troglexuma (from Exuma Cays, Cat Island, and Eleuthera) were based have been re-examined when possible. The diagnostic identifying characters and purported apomorphies for Lucayalana gen. n. are: frontal lamina short, narrow, less than 7% width of labrum, not extending to anterior margin of head; pleonite 3 extending posteriorly to posterior of pleonite 5, laterally overlapping pleonites 4 and 5; ventrally broad, forming a strong ventrally directed blade; pereopods 1-3 merus inferior margin RS not molariform. Mitochondrial COI and 16S loci and the nuclear 18S locus data show that all specimens are the one species. Comparison to additional cirolanid COI sequence data RESEARCH ARTICLE Subterranean BiologyPublished by The International Society for Subterranean Biology A peer-reviewed open-access journal Niel L. Bruce et al. / Subterranean Biology 21: 57-92 (2017) 58(BOLD, GenBank) show that Lucayalana troglexuma is genetically distinct to all other cirolanid genera with available COI sequences. The single male and females have shared COI (with three females), 16S (eight females) and 18S sequences (two females).

<p>The dynamic interaction between synoptic systems across the Iranian Plateau in West Asia has made this region highly sensitive to climate change.   Early human migration routes in the region from Africa to Eurasia are marked by Paleolithic sites and provide a unique opportunity to study the impact of climate variability on early human mobility and settlement. Preliminary results are based on δ<sup>18</sup>O and elemental time series from three stalagmites in central-northwest Iran with robust U-Th chronology over the last 450,00 years The data raise the possibility that the Iranian Plateau experienced several episodes of wet conditions during the Paleolithic period. This is in line with findings from a compilation of independent proxy records of lake sediment in northwest Iran and loess deposits in northeast Iran. The fluctuation of Mn abundance and δ<sup>18</sup>O values in these stalagmites correlate with the Greenland ice core record (NGRIP) and coincide with periods of high solar intensity in the northern hemisphere. These early results indicate wet conditions may have prevailed over the Iranian Plateau during marine isotope stages MIS5a,b, MIS5c, MIS5e, MIS6b, MIS6d-e and most likely also during stages MIS3-4 and MIS7a. Early human occupation of the Southern Caucasus, Zagros, and the Near East regions coincides with the upper Pleistocene wet periods. The co-variability between the proxy data from these speleothems and solar insolation at 30°N suggests that early human settlements/occupations may have been more prevalent along coastal regions of the Near East during dry climate episodes.</p>

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