Borers and encrusters as indicators of the presence of hermit crabs in Antarctic Eocene gastropods shells

2007 ◽  
Vol 19 (3) ◽  
pp. 297-309 ◽  
Author(s):  
Silvio Casadio ◽  
Ana Parras ◽  
Miguel Griffin ◽  
Sergio Marenssi
Keyword(s):  
Antarctic Peninsula ◽  
Hermit Crabs ◽  
Lower Section ◽  
Temperate Water ◽  
Independence Test ◽  
Chi Square ◽  
La Meseta Formation ◽  
Boring Organisms ◽  
Encrusting Organisms

AbstractThe community of encrusting and boring organisms developed on shells of the gastropod Antarctodarwinella ellioti from the lower section of the La Meseta Formation (Eocene) exposed on Seymour (Marambio) Island, Antarctic Peninsula, allows inference that the shells were inhabited by hermit crabs. A Chi-square Independence Test revealed that the community - dominated by polychaetes and bryozoans - shows preference for the aperture interior area of the shell. A subsequent Cochran Q Test indicated that the differences in frequency of encrusting and boring organisms as counted on the different interior sectors of the aperture were statistically significant. Thus, polychaetes, boring bryozoans, and encrusting bryozoans, do not show the same frequency in each interior sector of the aperture; they are more frequent on the columella (P < 0.0001, P < 0.01 and P < 0.001 respectively). Encrusting bryozoans also appear to show a preference - albeit not as high as on the columella - for the outer lip. This community of boring and encrusting organisms and their distribution on the shell confirms that the shells were inhabited by hermit crabs. The community is similar to that described in Recent hermitted shells from mid-latitude temperate water environments, suggesting that such communities were already established in the Eocene.

scholarly journals Analysis of Factors Giving the Opportunity for Implementation of Innovations on the Example of Manufacturing Enterprises in the Silesian Province

2019 ◽  
Vol 11 (20) ◽  
pp. 5850 ◽  
Author(s):  
Henryk Wojtaszek ◽  
Ireneusz Miciuła
Keyword(s):  
Competitive Advantage ◽  
Descriptive Statistics ◽  
Survey Questionnaire ◽  
Manufacturing Companies ◽  
Incentive Systems ◽  
Independence Test ◽  
Chi Square ◽  
Manufacturing Enterprises ◽  
Sample Test ◽  
Implementation Of Innovations

This paper analyzes the actions that improve innovativeness in production enterprises in the Silesian province. Innovation is one of the elements that allows to achieve a competitive advantage. It is justified to research various factors that are important in improving innovativeness. The research includes selected production enterprises in the Silesian province, adopting the descriptive statistics measures and statistic tests: random sample test, chi-square independence test and the non-parametric Kruskal-Wallis test based on a survey questionnaire. Some of the most important factors determining the possibilities of innovation by manufacturing companies were detected contacts with other enterprises, R&D centers and counseling institutions, competitive position of the company, and creating appropriate incentive systems.

The youngest record of fossil land mammals from Antarctica; its significance on the evolution of the terrestrial environment of the Antarctic Peninsula during the late Eocene

1997 ◽  
Vol 71 (2) ◽  
pp. 348-350 ◽  
Author(s):  
S. F. Vizcaino ◽  
M. Bond ◽  
M. A. Reguero ◽  
R. Pascual
Keyword(s):  
Antarctic Peninsula ◽  
Present Note ◽  
Late Eocene ◽  
South American ◽  
Terrestrial Environment ◽  
Shallow Marine ◽  
Early Oligocene ◽  
La Meseta Formation ◽  
The Antarctic ◽  
Seymour Island

The record of fossil land mammals from Antarctica has been restricted previously to the middle levels of the Eocene-?early Oligocene La Meseta Formation in Seymour Island, Antarctic Peninsula. This mostly shallow-marine sequence was divided informally into seven subunits (Tertiary Eocene La Meseta or TELM 1 to 7) by Sadler (1988). Land mammals, representing South American lineages of marsupials, edentates, and ungulates were recovered from TELM 3, 4, and 5 (Marenssi et al., 1994; Vizcaíno et al., 1994). The purpose of the present note is to report the discovery of a well-preserved ungulate tooth from the uppermost level of the La Meseta Formation (TELM 7) and to discuss its paleoenvironmental implications.

scholarly journals Gender Differences in the Experience of Infertility Concerning Polish Couples: Preliminary Research

2019 ◽  
Vol 16 (13) ◽  
pp. 2337 ◽  
Author(s):  
Małgorzata Nagórska ◽  
Anna Bartosiewicz ◽  
Bogdan Obrzut ◽  
Dorota Darmochwał-Kolarz
Keyword(s):  
Assisted Reproductive Technologies ◽  
Reproductive Technologies ◽  
Clinical Pregnancy ◽  
World Health ◽  
Independence Test ◽  
Chi Square ◽  
Unprotected Sexual Intercourse ◽  
The World ◽  
Preliminary Research ◽  
Health Organization

The World Health Organization (WHO) determines infertility as a disease of the reproductive system defined clinically by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse. Estimates indicate that the problem of infertility in the world is continuing to grow. The aim of the study was to compare approaches to disease in partners of both sexes diagnosed with infertility. The study was conducted among 61 couples treated for infertility using an original questionnaire developed by the authors. The Chi square independence test was used for statistical analysis. Both men and women responded to the diagnosis of infertility with negative emotions. Regardless of sex, sadness and anxiety were the dominant feelings associated with the diagnosis of infertility. Women believed in the success of the treatment to a greater extent than men. Mainly women attempted to talk openly about the problem of infertility, while men were more restrained in this respect. Women accepted the assisted reproductive technologies (ART) to a greater extent than men, but men would accept childlessness more often than women.

Eocene crinoids from Seymour Island, Antarctic Peninsula: paleobiogeographic and paleoecologic implications

1993 ◽  
Vol 67 (2) ◽  
pp. 250-257 ◽  
Author(s):  
David L. Meyer ◽  
Tatsuo Oji
Keyword(s):  
Antarctic Peninsula ◽  
Surface Waters ◽  
Systematic Position ◽  
La Meseta Formation ◽  
Mode Of Life ◽  
The Antarctic ◽  
Favorable Temperature ◽  
A New Species ◽  
Seymour Island ◽  
Water Facies

On the basis of recent collections from the Upper Eocene La Meseta Formation of Seymour Island, Antarctic Peninsula, the morphology, systematic position, taphonomy, and paleoecology of the isocrinid Metacrinus fossilis are investigated. A new species, Notocrinus rasmusseni, is described as the first comatulid crinoid known from the Antarctic fossil record. The systematic assignment of M. fossilis is maintained. Basal abrasion of calyxes and absence of long attached columns suggest that M. fossilis might have lost most of the column in adult stages and lived directly on the substratum, supported by some arms and a few cirri, similar to comatulids. About 10 percent of M. fossilis individuals show brachial regeneration, in contrast to regeneration frequencies of 70–90 percent among modern Japanese isocrinids. The anomalous occurrence of isocrinids in shallow-water facies of the La Meseta is attributed to a combination of reduced predation pressure, the presumed stalkless mode of life, and a favorable temperature regime in Antarctic surface waters prior to the onset of cooling at the close of the Eocene.

scholarly journals The earliest fossil record of a medium-sized penguin

2011 ◽  
Vol 32 (3) ◽  
pp. 269-277 ◽  
Author(s):  
Piotr Jadwiszczak ◽  
Sandra Chapman
Keyword(s):  
Antarctic Peninsula ◽  
Early Phase ◽  
Fossil Record ◽  
Taxonomic Diversity ◽  
Distal Humerus ◽  
Early Eocene ◽  
British Antarctic Survey ◽  
Early Eocene Climatic Optimum ◽  
La Meseta Formation ◽  
Seymour Island

The earliest fossil record of a medium-sized penguinThe fossil record of Antarctic Sphenisciformes dates as early as the late Palaeocene Cross Valley Formation, Seymour Island, Antarctic Peninsula. However, the best known Antarctic locality for early penguin remains (mainly isolated bones) is the Eocene La Meseta Formation that outcrops in the northeast of Seymour Island. The analysis of an unstudied set of specimens collected there by members of the British Antarctic Survey in 1989 has resulted in identification of a distal humerus from the unit Telm3 (early Eocene) of the formation that is the oldest known bone attributable to a medium-sized (in the context of the entire Cainozoic era) penguin. This find suggests that the origin of these birds, in conjunction with an increase in taxonomic diversity of the Eocene Sphenisciformes, was related to the Early Eocene Climatic Optimum (EECO) or, more probably, the early phase of subsequent cooling.

scholarly journals Analysis of Factors Giving the Opportunity for Implementation of Innovations on the Example of Manufacturing Enterprises in the Silesian Province

2019 ◽  
Author(s):  
Henryk Wojtaszek ◽  
Ireneusz Miciuła
Keyword(s):  
Competitive Advantage ◽  
Descriptive Statistics ◽  
Survey Questionnaire ◽  
Manufacturing Companies ◽  
Incentive Systems ◽  
Independence Test ◽  
Chi Square ◽  
Manufacturing Enterprises ◽  
Sample Test ◽  
Implementation Of Innovations

The paper analyzes the actions that improve innovativeness in production enterprises in the Silesian province. Innovation is one of the elements that allows to achieve a competitive advantage. It turns out justified to research various factors that are important in improving innovativeness. The research includes selected production enterprises in the Silesian province, adopting the descriptive statistics measures and statistic tests: random sample test, chi-square independence test and the non-parametric Kruskal-Wallis test based on a survey questionnaire. As part of the most important factors determining the possibilities of innovation by manufacturing companies were detected contacts with other enterprises, R&amp;D centers and counseling institutions, competitive position of the company and creating appropriate incentive systems.

scholarly journals Partial limb skeleton of a “giant penguin” Anthropornis from the Eocene of Antarctic Peninsula

2012 ◽  
Vol 33 (3) ◽  
pp. 259-274 ◽  
Author(s):  
Piotr Jadwiszczak
Keyword(s):  
Antarctic Peninsula ◽  
Fossil Record ◽  
Large Scale ◽  
Single Individual ◽  
Antarctic Species ◽  
Late Paleocene ◽  
La Meseta Formation ◽  
Functional Analyses ◽  
The Antarctic

Abstract: The fossil record of the Antarctic penguins is dated to the late Paleocene of Sey− mour (Marambio) Island, but the largest sphenisciforms, generaAnthropornisandPalae−eudyptes, originate from the Eocene La Meseta Formation. Here, the most complete large−scale reconstruction of a limb skeleton (a whole wing and a partial hind leg) of a Paleogene Antarctic penguin is reported. All bones are attributable to a single individual identified asAnthropornissp. The comparative and functional analyses of the material indi− cate that this bird was most probably well−adapted to land and sea while having a number of intriguing features. The modern−grade carpometacarpal morphology is unique among known Eocene Antarctic species and all but one more northerly taxa.

Record of Late Miocene glacial deposits on Isla Marambio (Seymour Island), Antarctic Peninsula

2009 ◽  
Vol 22 (2) ◽  
pp. 193-198 ◽  
Author(s):  
Sergio A. Marenssi ◽  
Silvio Casadío ◽  
Sergio N. Santillana
Keyword(s):  
Antarctic Peninsula ◽  
Late Miocene ◽  
Late Eocene ◽  
Weddell Sea ◽  
Volcanic Group ◽  
Lower Oligocene ◽  
La Meseta Formation ◽  
James Ross Island ◽  
Stratigraphic Sequences ◽  
Seymour Island

AbstractWe report and describe two new small diamictite outcrops on Isla Marambio (Seymour Island), Antarctic Peninsula. These rocks rest on an erosional unconformity on top of the Eocene La Meseta Formation and are unconformably covered by glaciomarine rocks of the ?Pliocene–Pleistocene Weddell Sea Formation. The lithology, fossil content and isotopic ages obtained strongly suggest that the rocks belong to the Hobbs Glacier Formation and support a Late Miocene age for this unit. Additionally, the dated basalt clast provides the oldest age (12.4 Ma) for the James Ross Island Volcanic Group recorded up to now. The here described diamictite cannot be confidently correlated with a glaciomarine unit previously assigned to the Late Eocene–Lower Oligocene taken as proof that initial expansion of ice on Antarctica encompassed the entire continent synchronously in the earliest Oligocene. However, it is now evident that there are likely to be more, short but important, stratigraphic sequences of key regional and Antarctic wide interest preserved on the plateau of Isla Marambio.

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