Geographical Distribution Of Sites Research Articles

Variations by degrees: Western European paleoenvironmental fluctuations across MIS 13–11

Marine Isotope Stages (MIS) 13–11 saw a major transformation in the hominin occupation of Europe, with an expansion in the scale and geographical distribution of sites and artifact assemblages. That expansion is explored here in the context of paleoenvironmental variability, focusing on geographical and chronological trends in climatic and habitat conditions at and between key Lower Paleolithic sites in Western Europe. Climatic conditions at British sites are compared across MIS 13–11, and used to test predicted values from the Oscillayers data set. Conditions at hominin and nonhominin sites are compared to explore possible limitations in hominin tolerances during MIS 13–11. Trends in conditions are explored with reference to long-term global patterns, short-term substage events, and seasonal variations. The apparent increase in the scale of hominin activity in north-western Europe during MIS 13 is surprising in light of the relatively harsh conditions of late MIS 13, and is likely to reflect significant physiological and/or behavioral adaptations, a mild south-north temperature gradient in western Europe during MIS 13, and the relatively mild, sustained conditions spanning MIS 15–13. The expanded occupation of north-western Europe during MIS 11 probably reflects the extended mild conditions of MIS 11c, since marked seasonal temperature differences and substantial behavioral changes between hominin sites in MIS 13 and 11 are not clearly evident. Site-specific conditions in south-western Europe during MIS 11 suggest milder winters, warmer summers, and reduced seasonal variability compared to north-western Europe. Some or all of these conditions may have supported larger, core populations, as may the relatively mild conditions associated with south-western European sites during MIS 12. Finally, comparisons between north-western and north-central European sites indicate relatively small differences in seasonal temperatures, suggesting that climate may only be a partial factor behind the smaller-scale occupations of north-central Europe during MIS 13–11.

Toward a New Understanding of the Alignment of Ancient Egyptian Sites

It is generally believed that the ancient Egyptians oriented their pyramids, temples, and other structures to the sun and stars. Yet the alignments of many sites are either unexplained or are not consistent with accepted historical timelines. Even if one knew nothing about the Egyptian civilization it can be readily determined that many sites are oriented astronomically. In a study of 650 locations throughout Egypt, we identify 113 sites that are aligned in the cardinal directions, or to solstices, or lunar standstills. Using a new shifted geographic pole alignment model based on Charles Hapgood’s theory of crustal displacements and geographic pole shifts to test the remaining sites an additional 60 sites were found that could have been astronomically aligned relative to previous locations of the North Pole. We propose that when these sites were first established they were aligned relative to the location of the geographic pole at the time but are now misaligned to the current pole due to subsequent pole shifts. Based solely on their alignment we hypothesize that these sites were built tens of thousands of years ago under the earlier pre-dynastic reigns listed in the Turin Papyrus. Analyzing the geographic distribution of sites aligned to current and past poles reveals a difference in the alignment statistics between Upper and Lower Egypt that could be explained by a flood or other disaster following the last pole shift.

Understanding the relationship between stream metabolism and biological assemblages

Biological assemblages are commonly used for assessing stream health, but there is increased interest among the freshwater research community in incorporating measures of stream function, such as metabolism, to strengthen stream-health assessments. Presently, there is limited information about the relationships between stream metabolism and biological assemblages, along with the measurement period required to relate metabolism with stream biota. Our study assessed which environmental factors explained stream metabolism and to what degree stream metabolism and minimum dissolved oxygen (DOmin) were related to invertebrate and fish metrics in streams distributed across several regions of the United States. Furthermore, we evaluated the number of metabolism monitoring days required for maximizing the ability to detect relationships between stream metabolism and biological assemblage metrics. We sampled 17 sites distributed among reference, agricultural, and urban areas for stream metabolism, nutrients, habitat, and biological assemblages (invertebrates and fishes). Overall, sites were heterotrophic with gross primary production (GPP) and ecosystem respiration (ER) related primarily to days since last high flow, canopy cover, maximum water temperature, and total phosphorus. DOmin was related to days since last high flow, canopy cover, and maximum water temperature. We were unable to determine a clear statistical relationship between invertebrate metrics (invertebrate richness; Ephemeroptera, Plecoptera, and Trichoptera richness; and scraper-taxa richness) and GPP, ER, or DOmin. In contrast, we found that 2 fish-assemblage metrics were associated with stream metabolism and DOmin. A fish multimetric index (FMMI) was negatively correlated with GPP (r = −0.5, p = 0.048) and positively correlated with DOmin (r = 0.47, p = 0.06). Percentage of omnivorous fish taxa was positively correlated with GPP (r = 0.72, p = 0.001) and ER (r = 0.55, p = 0.02) and negatively correlated with DOmin (r = −0.67, p = 0.003). The lack of detected relationships for most of the biological-assemblage metrics with stream metabolism may be partially due to 1 or more factors, including high variability, low sample size, limited range in metabolism values, assemblage metrics used, and geographic distribution of sites. Comparing stream-metabolism measurement periods (in days) to biological-assemblage metrics indicated that optimum correlations occurred at 2 d for DOmin, 3 d for GPP, and 14 d for ER. Although our study found limited relationships of stream metabolism and DOmin with biological assemblages, future studies should consider a larger sample size (≥30), 14-d or longer metabolism measurement period, and assessment of other taxa-specific or assemblage metrics.

Geographical distribution of Pleistocene cold-adapted large mammal faunas in the Iberian Peninsula

Cold-adapted large mammal faunas reached the Iberian Peninsula during the coldest periods of the Late Pleistocene. A total of 75 Iberian sites yielded remains of the cold-adapted faunal complex which is composed of the species, Mammuthus primigenius (woolly mammoth), Coelodonta antiquitatis (woolly rhinoceros), Rangifer tarandus (reindeer) and, to a lesser extent, Gulo gulo (wolverine), Alopex lagopus (arctic fox), Ovibos moschatus (musk-ox) and Saiga tatarica (saiga antelope). All published information about localities containing cold-adapted large mammal species has been compiled and interpreted according to its geographical location and chronology. Discussion is focused on examining European faunal corridors into Iberia, particularly during cold phases and concentrating on routes to the central and southern part of the peninsula. Three main episodes with presence of cold-adapted faunas appear to occur within the Iberian Peninsula. The geographic distribution of sites containing the remains of cold-adapted species differs among the three episodes. The oldest occurrence of cold-adapted taxa has been dated around 200–100 ka BP. During this time, the southern limit appears to be about 40°N latitude (∼Madrid). During the following episode, between 42 and 31 ka BP, the southernmost limit of cold-adapted fauna is identified by woolly mammoth ( M. primigenius) remains at Padul, Granada, (37°01′01′N) near the southernmost part of the peninsula. Cold-adapted species appear to be limited to the northern part of the Iberian Peninsula during the last episode, which occurred during the Last Glacial Maximum (LGM) and Younger Dryas (YD).

Paleoceanography and the diachrony of radiolarian events in the eastern equatorial Pacific

The development of an orbitally tuned time scale for the ODP leg 138 sites provides biostratigraphers a very high resolution chronostratigraphic framework. With this framework we are better able to define which of the first and last appearances of species appear to be synchronous. In addition, the geographic distribution of sites provides the means with which the detailed spatial patterns of invasion of new species and the extinction of older species can be mapped. These maps not only provide information on the process of evolution, migration, and extinction, they can also be related to water mass distributions and near‐surface circulation of the ocean. Of 39 radiolarian events studied at 11 sites in the eastern equatorial Pacific, 28 were found to have a minimum range in their estimated age that exceeded 0.15 m.y. The temporal pattern of first and last appearances of these diachronous events have coherent spatial patterns that indicate shifts in the areas of high oceanographic gradients over the past 10 Ma. These changes in the locations of high gradient regions suggest that the South Equatorial Current (SEC) was north of its present position prior to approximately 7 Ma. There was a southward shift in the northern boundary of this current between approximately 6 and 7 Ma, and the development of a relatively strong gradient between the northeastern and northwestern sites. Between approximately 3.7 and 3.4 Ma, there was a very slight northward shift in the northern boundary of the SEC and the steep gradients between the northeastern and northwestern sites may have disappeared. This change is thought to be associated with the closing of the Isthmus of Panama. The temporal‐spatial patterns of diachronous events younger than 3.4 Ma are consistent with patterns of circulation in the modern ocean.

Evaluation of locations for testing dry bean cultivars in western Canada using statistical procedures, biological interpretation and multiple traits

Genotype × environment (GE) effects in regional registration trials for dry beans in western Canada were studied to determine whether geographic distribution of sites could be rationalized. The structure of the GE effects on the maturity, seed weight and seed yield of seven dry bean check cultivars grown at eight locations during 4 yr was investigated using GE mean squares decomposition, cluster analysis and the additive main effect and multiplicative interaction (AMMI) method. The analyses revealed a high level of redundancy in the locations which suggested that most GE effects can be captured with fewer testing sites. The partition of the GE mean squares demonstrated the possibility of reproducing the GE structure of the entire data sets with as few as three sites; however, more locations may be needed to compensate for unpredictable environmental effects. Based on biological interpretation of groupings and visual assessment of the AMMI displays, a five-location set fully represented the GE effects on maturity, seed weight and seed yield and accounted for the inconsistent clustering of the Brooks site for the three traits. Also, the set should allow for site losses due to unpredictable environmental events. The dry bean industry in western Canada is expanding to non-traditional growing areas and the establishment of trials in these areas should be considered as they may create GE effects not considered to date. Key words: Phaseolus vulgaris L., genotype × environment interactions, cluster analysis, AMMI analysis

Cough/Cold Preparations

Cold-adapted large mammal faunas reached the Iberian Peninsula during the coldest periods of the Late Pleistocene. A total of 75 Iberian sites yielded remains of the cold-adapted faunal complex which is composed of the species, Mammuthus primigenius (woolly mammoth), Coelodonta antiquitatis (woolly rhinoceros), Rangifer tarandus (reindeer) and, to a lesser extent, Gulo gulo (wolverine), Alopex lagopus (arctic fox), Ovibos moschatus (musk-ox) and Saiga tatarica (saiga antelope).All published information about localities containing cold-adapted large mammal species has been compiled and interpreted according to its geographical location and chronology.Discussion is focused on examining European faunal corridors into Iberia, particularly during cold phases and concentrating on routes to the central and southern part of the peninsula. Three main episodes with presence of cold-adapted faunas appear to occur within the Iberian Peninsula. The geographic distribution of sites containing the remains of cold-adapted species differs among the three episodes. The oldest occurrence of cold-adapted taxa has been dated around 200–100 ka BP. During this time, the southern limit appears to be about 40°N latitude (∼Madrid). During the following episode, between 42 and 31 ka BP, the southernmost limit of cold-adapted fauna is identified by woolly mammoth (M. primigenius) remains at Padul, Granada, (37°01′01′N) near the southernmost part of the peninsula. Cold-adapted species appear to be limited to the northern part of the Iberian Peninsula during the last episode, which occurred during the Last Glacial Maximum (LGM) and Younger Dryas (YD).