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951.
Moon snail predation on clams is a common model system of predator–prey interactions. In this system, the predator bores through the shell of its prey, leaving a distinct and identifiable hole. Some paleoecological and behavioral research on moon snails suggests a trend in predation preference directed toward clams with small shells. Rarely, however, have studies tested relative drilling frequencies across species and size ranges in natural assemblages of clam communities. We examined the clam community composition at two beaches in South Carolina, USA, and we then tested moon snail predator preferences for (a) clam prey species and (b) whether their selection is related to prey shell size. We collected a total of 1,879 clam shells, identified each shell to species and recorded their anteroposterior length. The species composition of clams differed significantly between the two beaches; Anadara ovalis was dominant at both sites, but three of ten total species were only collected at one beach. Folly Beach had nearly a 60% higher the overall drilling frequency (34.6%) versus Edisto Beach (21.8%), and this may be linked to the differences in clam community compositions at the sites. For A. ovalis and Mulinia lateralis, shells with larger lengths have lower probabilities of being bored by a moon snail. Anadara brasiliana, which generally is a thinner‐shelled clam species, had the highest total drilling frequency (77.2%), and Noetia ponderosa, a thicker‐shelled clam, had a considerably lower drilling frequency (12.0%). We conclude that both community level factors (species composition) and population characteristics (shell size distributions) may influence the local drilling frequency by moon snails.  相似文献   
952.
Structure of the basins of the White Sea rift systems   总被引:1,自引:0,他引:1  
For the first time, the structure of the sedimentary basins of the Late Proterozoic rift system in the White Sea is characterized based on a set of new marine geological geophysical data such as the results of the common depth point seismic method, gravity and magnetic data, and seismoacoustics. The main tectonic structures in the topography of the heterogeneous basement within the basin of the White Sea are distinguished and described. A structural tectonic scheme of the basement surface is presented. The thicknesses of the sediments are estimated and the stratigraphic confinement of the seismic units recognized is done.  相似文献   
953.
Polunina  Ju. Ju.  Lange  E. K.  Krechik  V. A. 《Oceanology》2019,59(1):66-74
Oceanology - Specific features of the structure and distribution of autumn zooplankton in the southeastern Baltic Sea (SEB) in October 2015 have been found taking into account the hydrological and...  相似文献   
954.
Cherbadgy  I. I.  Propp  L. N. 《Oceanology》2019,59(4):514-522
Oceanology - The influence of habitat depth on the content of organic carbon (Corg), as well as organic and mineral forms of nitrogen (N) and phosphorus (P), in the biocenosis of coralline algae at...  相似文献   
955.
Kosolapova  N. G.  Kosolapov  D. B.  Kopylov  A. I.  Romanenko  A. V. 《Oceanology》2019,59(6):881-892
Oceanology - For the first time, the species composition of heterotrophic nanoflagellates, their quantitative characteristics, and abundance and biomass of their main food objects—bacteria...  相似文献   
956.
Pereskokov  A. I. 《Oceanology》2019,59(6):823-828
Oceanology - One of the key problems of physical oceanology is the search for effective global mechanisms that can result in formation and sustainability of the oceanic thermohalocline, which...  相似文献   
957.
Leont’yev  I. O. 《Oceanology》2019,59(2):267-275
Oceanology - A model of an artificial beach is proposed for protecting a seacoast subjected to erosion under significant storm surge impact. The beach profile properties are based on the Dean...  相似文献   
958.
Izvestiya, Atmospheric and Oceanic Physics - Sea-ice monitoring using long-term data from satellite passive microwave instruments allows one to make quantitative estimates of climatic trends. These...  相似文献   
959.
Izvestiya, Atmospheric and Oceanic Physics - The permanent analysis of the hydrogeodeformation (HGD) field is one promising direction in the field of predicting strong earthquakes. As a result of...  相似文献   
960.
Izvestiya, Atmospheric and Oceanic Physics - The technique for constructing the spatial distribution of maximum aerosol optical depth (MAOD) has been used to estimate the optically dense haze...  相似文献   
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