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Full-Text Articles in Life Sciences

The Phylogeny Of Paralabrax (Perciformes: Serranidae) And Allied Taxa Inferred From Partial 16s And 12s Mitochondrial Ribosomal Dna Sequences, Daniel Pondella, Matthew Craig, Jens Frank Sep 2003

The Phylogeny Of Paralabrax (Perciformes: Serranidae) And Allied Taxa Inferred From Partial 16s And 12s Mitochondrial Ribosomal Dna Sequences, Daniel Pondella, Matthew Craig, Jens Frank

Daniel Pondella

Partial sequences of 16S and 12S mitochondrial ribosomal DNA were used to examine the phylogenetic relationships of the primarily eastern Pacific genus Paralabrax (Perciformes: Serranidae) and allied taxa. Paralabrax is considered a basal serranine, which is itself considered the basal subfamily in the Serranidae. Multiple serranines reported closely related to Paralabrax from the genera Serranus, Hypoplectrus, Cratinus, and Centropristis were used as outgroups. Species from the remaining two subfamilies, Epinephilinae and Anthiinae, of the Serranidae were also used in the analyses. The tree of the Serranidae was rooted with the families Polyprionidae and Priacanthidae. Paralabrax, the Serranidae, and the Serraninae …


An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne H. Alonzo, Paul Switzer, Marc Mangel Jan 2003

An Ecosystem-Based Approach To Management: Using Individual Behaviour To Predict The Indirect Effects Of Antarctic Krill Fisheries On Penguin Foraging, Suzanne H. Alonzo, Paul Switzer, Marc Mangel

Paul V. Switzer

Summary 1. Changes in species' abundance and distributions caused by human disturbances can have indirect effects on other species in a community. Although ecosystem approaches to management are becoming increasingly prevalent, they require a fuller understand- ing of how individual behaviour determines interactions within and between species. 2. Ecological interactions involving krill are of major importance to many species within the Antarctic. Despite extensive knowledge of the ecosystem that they occupy, there is still incomplete understanding of the links between species and the effect of environmental conditions on these interactions. In this study, we extended a behavioural model used previously …


Ecological Games In Space And Time: The Distribution And Abundance Of Antarctic Krill And Penguins, Suzanne H. Alonzo, Paul V. Switzer, Marc Mangel Jan 2003

Ecological Games In Space And Time: The Distribution And Abundance Of Antarctic Krill And Penguins, Suzanne H. Alonzo, Paul V. Switzer, Marc Mangel

Paul V. Switzer

The distribution and abundance of organisms are affected by behaviors, such as habitat selection, foraging, and reproduction. These behaviors are driven by interactions within and between species, environmental conditions, and the biology of the species in-volved. Although extensive theoretical work has explored predator–prey dynamics, these models have not considered the impact of behavioral plasticity and life-history trade-offs on predicted patterns. We apply a modeling method that allows the consideration of a spatial, dynamic ecological game between predators and prey using a life-history perspec-tive. As an illustrative example, we model the habitat selection of Antarctic krill and penguins during the time …


Effects Of Experience And Body Size On Refuge Choice In The Crayfish Orconectes Immunis, Patrick S. Forsythe, Deborah S. Wyatt, Paul V. Switzer Jan 2003

Effects Of Experience And Body Size On Refuge Choice In The Crayfish Orconectes Immunis, Patrick S. Forsythe, Deborah S. Wyatt, Paul V. Switzer

Paul V. Switzer

We investigated whether refuge size or experience with a refuge affected the refuge use of male Orconectes immunis crayfish. Individuals were given choices among seven refuges for 10 consecutive days. Refuges were formed from equal length but different diameter PVC pipe and placed in an array in a random sequence. Three treatments were used. In the Novel Refuge treatment, individuals were placed in a new test arena with a new arrangement of cleaned refuges every day. In the Nonremoval treatment, individuals were left in the same arena with the same set of refuges each day. In the Removal treatment, individuals …


Dangerous Animals In Captivity: Ex Situ Tiger Conflict And Implication For Private Ownership Of Exotic Animals, Philip J. Nyhus, Ronald L. Tilson, J L. Tomlinson Jan 2003

Dangerous Animals In Captivity: Ex Situ Tiger Conflict And Implication For Private Ownership Of Exotic Animals, Philip J. Nyhus, Ronald L. Tilson, J L. Tomlinson

Philip J. Nyhus

The risks associated with tiger attacks on people in the wild are well documented. There may currently be more tigers in captivity than in the wild, but relatively little is known about the risks of injury or death associated with owning and managing captive tigers and other large carnivores. The purpose of this study was to conduct a global assessment of attacks by captive tigers on people, with particular emphasis on cases in the United States. Our analysis of 30 international media sources and additional documents uncovered 59 unique incidents in 1998-2001 in which people were reportedly injured or killed …


Linear And Nonlinear Effects Of Habitat Structure On Composition And Abundance In The Macroinvertebrate Community Of A Large River, Timothy W. Stewart, Tammy L. Shumaker, Thomas A. Radzio Jan 2003

Linear And Nonlinear Effects Of Habitat Structure On Composition And Abundance In The Macroinvertebrate Community Of A Large River, Timothy W. Stewart, Tammy L. Shumaker, Thomas A. Radzio

Timothy W. Stewart

We used an experiment and regression analyses to quantify effects of spatial variation in habitat structure abundance on a riverine macroinvertebrate community under winter conditions. Concrete slabs (0.21 m2; n 5 24) with different numbers of stones (mean individual stone surface area 5 6.44 cm2) attached to upper faces were placed in the James River and retrieved after 28 d. Macroinvertebrate abundance and taxonomic richness on slabs were significantly positively related to stone abundance. Total macroinvertebrate abundance and abundance of oligochaetes (Nais spp.), Asiatic clams (Corbicula fluminea), caddisflies (Leptoceridae), riffle beetles (Elmidae) and stoneflies (Strophopteryx sp.) were linearly related to …


Characterization Of A Piscirickettsiosis-Like Disease In Hawaiian Tilapia., M. J. Mauel, Debra L. Miller, K. Frazier, A. Liggett, E. Styer, D. Montgomery-Brock, J. Brock Jan 2003

Characterization Of A Piscirickettsiosis-Like Disease In Hawaiian Tilapia., M. J. Mauel, Debra L. Miller, K. Frazier, A. Liggett, E. Styer, D. Montgomery-Brock, J. Brock

Debra L Miller

In 1994, tilapia (Oreochromis mossambicus and Sarotherodon melanotheron) in wild and farmed populations on Oahu, Hawaii, USA, began to die of an unknown disease that was similar but not identical to piscirickettsiosis in salmonids. Only tilapia were affected. Diseased tilapia often swam erratically and had trouble staying at depth. Scattered cutaneous haemorrhage and exophthalmia were often noted. In many cases, fish were found dead with no clinical signs. Gills exhibited epithelial hyperplasia with severe multifocal consolidation of secondary lamellae. Multiple granulomas were observed in the gills, spleen, kidney, choroid gland and testes, but not in the liver. Tilapia mortalities occurred …


Aehs: Contaminated Soil Sediment & Water (January/February 2003) Jan 2003

Aehs: Contaminated Soil Sediment & Water (January/February 2003)

Paul T. Kostecki

No abstract provided.


National Park Service Coastal Visitor Impact Monitoring Phase 2 Project Repor, Christopher Monz, H. Bauman, Y. Leung, C. Engle Jan 2003

National Park Service Coastal Visitor Impact Monitoring Phase 2 Project Repor, Christopher Monz, H. Bauman, Y. Leung, C. Engle

Christopher Monz

No abstract provided.


[James Mark] Baldwin And His Many Effects, David Depew Dec 2002

[James Mark] Baldwin And His Many Effects, David Depew

David J Depew

No abstract provided.


Evolution And Learning: The Baldwin Effect Reconsidered, David Depew, Bruce Weber Dec 2002

Evolution And Learning: The Baldwin Effect Reconsidered, David Depew, Bruce Weber

David J Depew

The role of genetic inheritance dominates current evolutionary theory. At the end of the nineteenth century, however, several evolutionary theorists independently speculated that learned behaviors could also affect the direction and rate of evolutionary change. This notion was called the Baldwin effect, after the psychologist James Mark Baldwin. In recent years, philosophers and theorists of a variety of ontological and epistemological backgrounds have begun to employ the Baldwin effect in their accounts of the evolutionary emergence of mind and of how mind, through behavior, might affect evolution.

The essays in this book discuss the originally proposed Baldwin effect, how it …


A New Species Of Phrynopus (Amphibia, Anura, Leptodactylidae) From The Puna Of Maraypata (Departamento De Huánuco, Peru), Edgar Lehr, Cesar Aguilar Dec 2002

A New Species Of Phrynopus (Amphibia, Anura, Leptodactylidae) From The Puna Of Maraypata (Departamento De Huánuco, Peru), Edgar Lehr, Cesar Aguilar

Edgar Lehr

A new medium-sized species of leptodactylid frog, genus Phrynopus is described from the puna of the eastern Andean slopes of central Peru (Departamento de Huanuco, 3 770m above sea level). The new species differs from all described species of the genus by having a pale brownish orange dorsal coloration, and a pale cream to orange ventral coloration. The new species lacks ear and vomerine teeth, and is most similar to P barthlenae with which it occurs sympatrically. Males of the new species are unknown.


The Impacts Of Aquacultured Oysters, Crassostrea Virginica (Gmelin, 1791) On Water Quality And Sedimentation: Results Of A Mesocosm Study, Michael A. Rice Dec 2002

The Impacts Of Aquacultured Oysters, Crassostrea Virginica (Gmelin, 1791) On Water Quality And Sedimentation: Results Of A Mesocosm Study, Michael A. Rice

Michael A Rice

To determine effects of aquacultured oysters Crassostrea virginica (Gmelin, 1791) on the overlying water column, a mesocosm study was performed at the Marine Ecosystem Research Laboratory (MERL) from June to October, 2000. The MERL facility is located adjacent to Narragansett Bay and consists of fourteen 13,000-l mesocosm tanks designed to simulate the Bay environmental conditions. Two hundred oysters (c35 mm valve height; nominally filtering about 55 l/day/individual) were placed into three mesocosms, and three mesocosms were maintained without oysters as controls. Experiments were run with varying rates of water exchange in the tanks ranging from 0% to 100% per day …


Evolutionary Relationships Of Deep-Sea Vent And Cold Seep Clams, Shana Goffredi, L A. Hurtado, S Hallam, R C. Vrijenhoek Dec 2002

Evolutionary Relationships Of Deep-Sea Vent And Cold Seep Clams, Shana Goffredi, L A. Hurtado, S Hallam, R C. Vrijenhoek

Shana Goffredi

Phylogenetic relationships among vesicomyid clams (Bivalvia: Vesicomyidae) and their placement within the order Heterodonta were examined using mitochondrial encoded cytochrome oxidase subunit I (COI) DNA sequences. The presently analyzed vesicomyids represent a recent monophyletic radiation that probably occurred within the Cenozoic. Nucleotide phylogenetic analyses resolved discrete clades that were consistent with currently recognized species: Calyptogena magnifica, C. ponderosa, Ectenagena extenta, C. phaseoliformis, Vesicomya cordata, Calyptogena n. sp. (Gulf of Mexico), C. kaikoi, C. nautilei, C. solidissima and C. soyoae (Type-A). However, specimens variously identified as: V. gigas, C. kilmeri, C. pacifica, and V. lepta comprised two “species complexes”, each composed …


Gradual Evolution In Bacteria: Evidence From Bacillus Systematics, M. Feldgarden, N. Byrd, Frederick M. Cohan Dec 2002

Gradual Evolution In Bacteria: Evidence From Bacillus Systematics, M. Feldgarden, N. Byrd, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.


From Behavior To Culture: An Assessment Of Cultural Evolution And A New Synthesis, Dwight W. Read Dec 2002

From Behavior To Culture: An Assessment Of Cultural Evolution And A New Synthesis, Dwight W. Read

Dwight W Read

Three approaches to cultural evolution—sociobiology, dual inheritance, and memes—are reviewed and it is shown that each makes use of an incomplete notion of what constitutes culture.


Incorporating Local Knowledge Into Population And Habitat Viability Assessments: Landowners And Tree Kangaroos In Papua New Guinea, Philip J. Nyhus, J Williams, J Borovansky, O Byers, P Miller Dec 2002

Incorporating Local Knowledge Into Population And Habitat Viability Assessments: Landowners And Tree Kangaroos In Papua New Guinea, Philip J. Nyhus, J Williams, J Borovansky, O Byers, P Miller

Philip J. Nyhus

No abstract provided.


Poetry, Music, And The Sustainability Of Language, Jan Wellington Dec 2002

Poetry, Music, And The Sustainability Of Language, Jan Wellington

Jan Wellington

No abstract provided.


Protecting Evolutionary Theory From Bad Company: J. Strick, Sparks Of Life: Darwinism And The Victorian Debates Over Spontaneous Generation (Review), David J. Depew Dec 2002

Protecting Evolutionary Theory From Bad Company: J. Strick, Sparks Of Life: Darwinism And The Victorian Debates Over Spontaneous Generation (Review), David J. Depew

David J Depew

No abstract provided.