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Full-Text Articles in Life Sciences

Adaptation To Hard-Object Feeding In Sea Otters And Hominins, Paul Constantino, James Lee, Dylan Morris, Peter Lucas, Adam Hartstone-Rose, Wah-Keat Lee, Nathaniel Dominy, Andrew Cunningham, Mark Wagner, Brian Lawn Sep 2012

Adaptation To Hard-Object Feeding In Sea Otters And Hominins, Paul Constantino, James Lee, Dylan Morris, Peter Lucas, Adam Hartstone-Rose, Wah-Keat Lee, Nathaniel Dominy, Andrew Cunningham, Mark Wagner, Brian Lawn

Paul J. Constantino

The large, bunodont postcanine teeth in living sea otters (Enhydra lutris) have been likened to those of certain fossil hominins, particularly the ’robust’ australopiths (genus Paranthropus). We examine this evolutionary convergence by conducting fracture experiments on extracted molar teeth of sea otters and modern humans (Homo sapiens) to determine how load-bearing capacity relates to tooth morphology and enamel material properties. In situ optical microscopy and x-ray imaging during simulated occlusal loading reveal the nature of the fracture patterns. Explicit fracture relations are used to analyze the data and to extrapolate the results from humans to earlier hominins. It is shown …


Bioretention: Evaluating Their Effectiveness For Improving Water Quality In New England Urban Environments, Mary Dehais Mar 2012

Bioretention: Evaluating Their Effectiveness For Improving Water Quality In New England Urban Environments, Mary Dehais

Mary Dehais

Nonpoint source (NPS) pollution is one of the leading causes of water quality problems in the United States. Bioretention has become one of the more frequently used stormwater management practices for addressing NPS pollution in urbanized watersheds in New England. Yet despite increased acceptance, bioretention is not widely practiced. This study explores and evaluates the efficacy of bioretention for protecting urban water quality. This research found that numerous monitoring methods are used by researchers and industry experts to assess the effectiveness of stormwater best management practices (BMPs) and low impact development (LID) practices that include bioretention. The two most common …


Clay Fabric And Mass Physical Properties Of Surficial Marine Sediment Near The Deepwater Horizon Oil Spill, Andrew Head, Richard H. Bennett, Jessica R. Douglas, Kenneth J. Curry Feb 2012

Clay Fabric And Mass Physical Properties Of Surficial Marine Sediment Near The Deepwater Horizon Oil Spill, Andrew Head, Richard H. Bennett, Jessica R. Douglas, Kenneth J. Curry

Kenneth J. Curry

Surficial sediment was obtained on the RV Cape Hatteras Cruise (2010) from the seafloor at a water depth of 1570 meters located at latitude 28°44'20.16"N and longitude 88°20'24.96"W in close proximity to the Deepwater Horizon well, Gulf of Mexico. Preliminary clay nano- and microfabric observation using a transmission electron microscope (TEM) depicted a sediment rich in clays and organic matter (OM) especially in the upper 2 cm subbottom. Initial analysis of TEM micrographs depicted a high porosity clay sediment. Initial study of the mass physical properties revealed water content ωt = 67.32 – 67.28% (percent total mass), porosity n= 84.1 …


A New Eusuchian Crocodyliform With Novel Cranial Integument And Its Significance For The Origin And Evolution Of Crocodylia, Casey Holliday, Nicholas Gardner Dec 2011

A New Eusuchian Crocodyliform With Novel Cranial Integument And Its Significance For The Origin And Evolution Of Crocodylia, Casey Holliday, Nicholas Gardner

Nicholas Gardner

Crocodyliforms were one of the most successful groups of Mesozoic tetrapods, radiating into terrestrial, semiaquatic and marine environments, while occupying numerous trophic niches, including carnivorous, insectivorous, herbivorous, and piscivorous species. Among these taxa were the enigmatic, poorly represented flat-headed crocodyliforms from the late Cretaceous of northern Africa. Here we report a new, giant crocodyliform from the early Late Cretaceous (Cenomanian) Kem Kem Formation of Morocco. Represented by a partial braincase, the taxon has an extremely long, flat skull with large jaw and craniocervical muscles. The skull roof is ridged and ornamented with a broad, rough boss surrounded by significant vascular …


Sharks Of The Devonian, Andrew Blitman Dec 2011

Sharks Of The Devonian, Andrew Blitman

Andrew Blitman

No abstract provided.


Landscape Management For Sustainable Supplies Of Bioenergy Feedstock And Enhanced Soil Quality, Douglas L. Karlen, David J. Muth Jr. Dec 2011

Landscape Management For Sustainable Supplies Of Bioenergy Feedstock And Enhanced Soil Quality, Douglas L. Karlen, David J. Muth Jr.

Douglas L Karlen

Agriculture can simultaneously address global food, feed, fi ber, and energy challenges provided our soil, water, and air resources are not compromised in doing so. As we embark on the 19th Triennial Conference of the International Soil and Tillage Research Organization (ISTRO), I am pleased to proclaim that our members are well poised to lead these endeavors because of our comprehensive understanding of soil, water, agricultural and bio-systems engineering processes. The concept of landscape management, as an approach for integrating multiple bioenergy feedstock sources, including biomass residuals, into current crop production systems, is used as the focal point to show …