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Full-Text Articles in Life Sciences
Ecosystem Properties Of Urban Land Covers At The Aboveground-Belowground Interface, Loren B. Byrne, Mary Ann Bruns, Ke Chung Kim
Ecosystem Properties Of Urban Land Covers At The Aboveground-Belowground Interface, Loren B. Byrne, Mary Ann Bruns, Ke Chung Kim
Arts & Sciences Faculty Publications
Understanding of ecological differences among urban land covers can guide the sustainable management of urbanized landscapes for conservation of ecosystem services. The objective of our study was to compare ecosystem properties at the aboveground–belowground interface of three land cover types commonly found in residential landscapes: lawns, bark mulch, and gravel mulch. Using unmowed vegetation as a reference land cover, we measured surface soil variables (to 5 cm depth), CO2 fluxes, and ground temperatures in experimental field plots within 3 years after their creation. Each land cover had a distinctive set of ecosystem properties. Mulched plots had significantly warmer soil and …
Proxy-Based Reconstructions Of Hemispheric And Global Surface Temperature Variations Over The Past Two Millennia, Michael E. Mann, Scott Rutherford
Proxy-Based Reconstructions Of Hemispheric And Global Surface Temperature Variations Over The Past Two Millennia, Michael E. Mann, Scott Rutherford
Arts & Sciences Faculty Publications
Following the suggestions of a recent National Research Council report [NRC (National Research Council) (2006) Surface Temperature Reconstructions for the Last 2,000 Years (Natl Acad Press, Washington, DC).], we reconstruct surface temperature at hemispheric and global scale for much of the last 2,000 years using a greatly expanded set of proxy data for decadal-to-centennial climate changes, recently updated instrumental data, and complementary methods that have been thoroughly tested and validated with model simulation experiments. Our results extend previous conclusions that recent Northern Hemisphere surface temperature increases are likely anomalous in a long-term context. Recent warmth appears anomalous for at least …
Evolutionary Physiology: The Extent Of C4 And Cam Photosynthesis In The Genera Anacampseros And Grahamia Of The Portulacaceae, Lonnie J. Guralnick, Amanda Cline, Monica Smith, Rowan F. Sage
Evolutionary Physiology: The Extent Of C4 And Cam Photosynthesis In The Genera Anacampseros And Grahamia Of The Portulacaceae, Lonnie J. Guralnick, Amanda Cline, Monica Smith, Rowan F. Sage
Arts & Sciences Faculty Publications
The Portulacaceae is one of the few terrestrial plant families known to have both C(4) and Crassulacean acid metabolism (CAM) species. There may be multiple origins of the evolution of CAM within the Portulacaceae but the only clear evidence of C(4) photosynthesis is found in members of the genus Portulaca. In the Portulaca, CAM succulent tissue is overlaid with the C(4) tissue in a unique fashion where both pathways are operating simultaneously. Earlier reports have shown that the clade containing the genera Anacampseros and Grahamia may also contain C(4) photosynthetic species similar to the Portulaca, which would indicate multiple origins …
Medusan Morphospace: Phylogenetic Constraints, Biomechanical Solutions, And Ecological Consequences, John H. Costello, Sean Colin, John O. Dabiri
Medusan Morphospace: Phylogenetic Constraints, Biomechanical Solutions, And Ecological Consequences, John H. Costello, Sean Colin, John O. Dabiri
Arts & Sciences Faculty Publications
Medusae were the earliest animals to evolve muscle-powered swimming in the seas. Although medusae have achieved diverse and prominent ecological roles throughout the world's oceans, we argue that the primitive organization of cnidarian muscle tissue limits force production and, hence, the mechanical alternatives for swimming bell function. We use a recently developed model comparing the potential force production with the hydrodynamic requirements of jet propulsion, and conclude that jet production is possible only at relatively small bell diameters. In contrast, production of a more complex wake via what we term rowing propulsion permits much larger sizes but requires a different …
Experimental Confirmation Of Protandric Simultaneous Hermaphroditism In A Caridean Shrimp Outside Of The Genus Lysmata, Helio Laubenheimer, Andrew L. Rhyne
Experimental Confirmation Of Protandric Simultaneous Hermaphroditism In A Caridean Shrimp Outside Of The Genus Lysmata, Helio Laubenheimer, Andrew L. Rhyne
Arts & Sciences Faculty Publications
Caridean shrimps display a variety of sexual systems including gonochorism and various forms of protandry but rarely simultaneous hermaphroditism. Protandric simultaneous hermaphroditism (PSH) has thus far only been demonstrated in the genus Lysmata. The first report of simultaneous hermaphroditism in a caridean shrimp was with Exhippolysmata ensirostris. However, this was not confirmed, since this species was also considered to be strictly protandric. Therefore, inconclusive results about this species’ true sexual system led us to examine Exhippolysmata oplophoroides. Mating between female phase individuals resulted in successful spawning, embryonic development and hatching of viable larvae. Furthermore, we have confirmed that this species …