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Full-Text Articles in Life Sciences

Critical Thermal Minima Of Age-0 Australian Bass, Macquaria Novemaculeata, Fingerlings: Implications For Stocking Programmes, Cameron M. Leo, Lee J. Baumgartner, Daniel J. Bucher, Wayne Robinson Apr 2013

Critical Thermal Minima Of Age-0 Australian Bass, Macquaria Novemaculeata, Fingerlings: Implications For Stocking Programmes, Cameron M. Leo, Lee J. Baumgartner, Daniel J. Bucher, Wayne Robinson

Dr Daniel J Bucher

Fishes are often stocked outside natural distribution ranges with inadequate information on target streams, particularly thermal regimes. Australian bass, Macquaria novemaculeata (Steindachner), is a catadromous species that is regularly stocked into upland reaches of rivers and impoundments in south-eastern Australia. Critical Thermal Minima (CTMin) were determined for age-0 Australian bass fingerlings with a mean fork length of 64.4 ± 0.4 mm and weighing 3.8 ± 0.8 g. Four treatments were used, including three replicate aquaria for each treatment. Fingerlings were acclimated at either 8 or 15 °C at densities of 15 fish in 56-L glass aquaria. Water temperatures were …


Ecosystems And Human Health:Toxicology And Environmental Hazards, Richard Philp Mar 2013

Ecosystems And Human Health:Toxicology And Environmental Hazards, Richard Philp

Richard B. Philp

This is a teaching text covering the toxicology of pollutants such as heavy metals and persistent organic pollutants, pesticides, as well as of animal and plant venoms and toxins. Environmental disasters are discussed and updated. There numerous case studies and each chapter has a self-evaluation quizz. See also www.amazon.com/Ecosystems-Human-Health-Toxicology-Environmental/dp/146656721


Selecting Zones In A Marine Park: Early Systematic Planning Improves Cost-Efficiency; Combining Habitat And Biotic Data Improves Effectiveness, H A. Malcom, E Foulsham, R L. Pressey, A Jordan, P L. Davies, T Ingleton, N Johnstone, S Hessey, Stephen Da Smith Mar 2013

Selecting Zones In A Marine Park: Early Systematic Planning Improves Cost-Efficiency; Combining Habitat And Biotic Data Improves Effectiveness, H A. Malcom, E Foulsham, R L. Pressey, A Jordan, P L. Davies, T Ingleton, N Johnstone, S Hessey, Stephen Da Smith

Professor Stephen DA Smith

Systematic planning, using algorithm tools, can improve biodiversity representation in ‘no-take’ zones in a marine park while reducing costs of meeting conservation targets. The current zoning plan for the 870 km2 Solitary Islands Marine Park (SIMP), designed without algorithm tools, provides an example to compare the efficiency of zoning scenarios that include or ignore the existing zoning scheme and to assess the utility of habitat and/or biotic data for planning. Marxan was used to compare representation of habitat categories and a selection of fish species using 3 scenarios for ‘no-take’ sanctuary zones: 1) clean slate; 2) building on the …


Pre-Settlement History May Obscure The Effect Of Forest Fragmentation On Genetic Variation In Eastern Red-Backed Salamanders, Mark Jordan, Douglas Morris, Scott Gibson Nov 2012

Pre-Settlement History May Obscure The Effect Of Forest Fragmentation On Genetic Variation In Eastern Red-Backed Salamanders, Mark Jordan, Douglas Morris, Scott Gibson

Mark A. Jordan

No abstract provided.


The Effects Of Water And Habitat Quality On Amphibian Assemblages In Two Midwest Watersheds, Abel Castaneda, Mark Jordan Nov 2012

The Effects Of Water And Habitat Quality On Amphibian Assemblages In Two Midwest Watersheds, Abel Castaneda, Mark Jordan

Mark A. Jordan

No abstract provided.


Potential Parthenogenesis In A Viperid Snake, Mark Jordan, Natasha Perrine Mar 2012

Potential Parthenogenesis In A Viperid Snake, Mark Jordan, Natasha Perrine

Mark A. Jordan

No abstract provided.


The Mirage Of A Space Between Nature And Nurture By Evelyn Fox Keller (Review), David Depew Feb 2012

The Mirage Of A Space Between Nature And Nurture By Evelyn Fox Keller (Review), David Depew

David J Depew

No abstract provided.


Environmental Issues For The Twenty-First Century And Their Impact On Human Health, Richard Philp Feb 2012

Environmental Issues For The Twenty-First Century And Their Impact On Human Health, Richard Philp

Richard B. Philp

This e-book documents environmental hazards from disasters such as the Gulf oil spill, from pollution resulting from resource exploitation, from contamination of the marine environment and from climate change including the role of human source greenhouse gases. Pollution from the electronic industry is a recent and serious threat to human and environmental health. The final chapter offers some means of preventing or reversing these hazards. Now available on Amazon


Population Genetics Of A Tolerant Fish In An Agriculturally Dominated Watershed, Mark Jordan, Deepal Patel, Matthew Richardville, Kathryn Sanders, Robert Gillespie Dec 2011

Population Genetics Of A Tolerant Fish In An Agriculturally Dominated Watershed, Mark Jordan, Deepal Patel, Matthew Richardville, Kathryn Sanders, Robert Gillespie

Mark A. Jordan

No abstract provided.


The Effects Of Land Sparing And Wildlife-Friendly Practices On Grassland Bird Abundance Within Organic Farmlands, John Quinn Dec 2011

The Effects Of Land Sparing And Wildlife-Friendly Practices On Grassland Bird Abundance Within Organic Farmlands, John Quinn

John E Quinn

No abstract provided.


Diversity Of Bacteria And Archaea In Hypersaline Sediment From Death Valley National Park, California, J.-S. Kim, M. Makama, J. Petito, N.-H. Park, Frederick M. Cohan, R. S. Dungan Dec 2011

Diversity Of Bacteria And Archaea In Hypersaline Sediment From Death Valley National Park, California, J.-S. Kim, M. Makama, J. Petito, N.-H. Park, Frederick M. Cohan, R. S. Dungan

Frederick M. Cohan

No abstract provided.


Island Fragmentation Drives Evolutionary Diversification Of Galápagos Lava Lizards (Microlophus Spp.), Mark Jordan, H. Snell Jul 2011

Island Fragmentation Drives Evolutionary Diversification Of Galápagos Lava Lizards (Microlophus Spp.), Mark Jordan, H. Snell

Mark A. Jordan

No abstract provided.


Phenotypic Divergence Despite High Levels Of Gene Flow In Galapagos Lava Lizards (Microlophus Albemarlensis), Mark Jordan, H. Snell, H. Snell, W. Jordan Jul 2011

Phenotypic Divergence Despite High Levels Of Gene Flow In Galapagos Lava Lizards (Microlophus Albemarlensis), Mark Jordan, H. Snell, H. Snell, W. Jordan

Mark A. Jordan

The extent of evolutionary divergence of phenotypes between habitats is predominantly the result of the balance of differential natural selection and gene flow. Lava lizards (Microlophus albemarlensis) on the small island of Plaza Sur in the Galápagos archipelago inhabit contrasting habitats: dense vegetation on the western end of the island thins rapidly in a transitional area, before becoming absent on the eastern half. Associated with these habitats are phenotypic differences in traits linked to predator avoidance (increased wariness, sprint speed, and endurance in lizards from the sparsely vegetated habitat). This population provides an opportunity to test the hypothesis that reduced …


The Influence Of Historical Landscape Change On Genetic Variation And Population Structure Of A Terrestrial Salamander ( Plethodon Cinereus ), Mark Jordan, Douglas Morris, Scott Gibson Jul 2011

The Influence Of Historical Landscape Change On Genetic Variation And Population Structure Of A Terrestrial Salamander ( Plethodon Cinereus ), Mark Jordan, Douglas Morris, Scott Gibson

Mark A. Jordan

Forest loss and fragmentation is expected to shape the genetic structure of amphibian populations and reduce genetic variation. Another factor widely understood to have impacted these same parameters in North America is the range expansion that occurred following glacial retreat at the end of the Pleistocene. The Eastern Red-Backed Salamander (Plethodon cinereus) has been subjected to both processes. In this context, we investigated the historical events that are likely to have shaped genetic variation in this species using a panel of six microsatellite markers screened on individuals sampled across ten localities in northeastern Indiana, USA. We found low genetic diversity …


Historical Fragmentation And Genetic Drift In Populations Of Galápagos Lava Lizards (Microlophus Albemarlensis Complex), Mark Jordan, H. Snell Jul 2011

Historical Fragmentation And Genetic Drift In Populations Of Galápagos Lava Lizards (Microlophus Albemarlensis Complex), Mark Jordan, H. Snell

Mark A. Jordan

No abstract provided.


Species-Level Correlates Of Susceptibility To The Pathogenic Amphibian Fungus Batrachochytrium Dendrobatidis In The United States, Betsy Bancroft, Barbara Han, Catherine Searle, Lindsay Biga, Deanna Olson, Lee Kats, Joshua Lawler, Andrew Blaustein May 2011

Species-Level Correlates Of Susceptibility To The Pathogenic Amphibian Fungus Batrachochytrium Dendrobatidis In The United States, Betsy Bancroft, Barbara Han, Catherine Searle, Lindsay Biga, Deanna Olson, Lee Kats, Joshua Lawler, Andrew Blaustein

Lee Kats

Disease is often implicated as a factor in population declines of wildlife and plants. Understanding the characteristics that may predispose a species to infection by a particular pathogen can help direct conservation efforts. Recent declines in amphibian populations world-wide are a major conservation issue and may be caused in part by a fungal pathogen, Batrachochytrium dendrobatidis (Bd). We used Random Forest, a machine learning approach, to identify species-level characteristics that may be related to susceptibility to Bd. Our results suggest that body size at maturity, aspects of egg laying behavior, taxonomic order and family, and reliance on water are good …


Adaptation As Process: The Future Of Darwinism And The Legacy Of Theodosius Dobzhansky, David Depew Feb 2011

Adaptation As Process: The Future Of Darwinism And The Legacy Of Theodosius Dobzhansky, David Depew

David J Depew

Conceptions of adaptation have varied in the history of genetic Darwinism depending on whether what is taken to be focal is the process of adaptation, adapted states of populations, or discrete adaptations in individual organisms. I argue that Theodosius Dobzhansky’s view of adaptation as a dynamical process contrasts with so-called “adaptationist” views of natural selection figured as “design-without-a-designer” of relatively discrete, enumerable adaptations. Correlated with these respectively process and product oriented approaches to adaptive natural selection are divergent pictures of organisms themselves as developmental wholes or as “bundles” of adaptations. While even process versions of genetical Darwinism are insufficiently sensitive …


The Complexity Of Amphibian Population Declines: Understanding The Role Of Cofactors In Driving Amphibian Losses, Andrew Blaustein, Barbara Han, Rick Relyea, Pieter Johnson, Julia Buck, Stephanie Gervasi, Lee Kats Feb 2011

The Complexity Of Amphibian Population Declines: Understanding The Role Of Cofactors In Driving Amphibian Losses, Andrew Blaustein, Barbara Han, Rick Relyea, Pieter Johnson, Julia Buck, Stephanie Gervasi, Lee Kats

Lee Kats

Population losses and extinctions of species are occurring at unprecedented rates, as exemplified by declines and extinctions of amphibians worldwide. However, studies of amphibian population declines generally do not address the complexity of the phenomenon or its implications for ecological communities, focusing instead on single factors affecting particular amphibian species. We argue that the causes for amphibian population declines are complex; may differ among species, populations, and life stages within a population; and are context dependent with multiple stressors interacting to drive declines. Because amphibians are key components of communities, we emphasize the importance of investigating amphibian declines at the …


Description Of The Tadpoles Of Hypsiboas Aguilari And H. Melanopleura Aguilari And H. Melanopleura (Anura: Hylidae: Hypsiboas Pulchellus Group), Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer Feb 2011

Description Of The Tadpoles Of Hypsiboas Aguilari And H. Melanopleura Aguilari And H. Melanopleura (Anura: Hylidae: Hypsiboas Pulchellus Group), Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer

Edgar Lehr

We describe the tadpoles of Hypsiboas melanopleura and H. aguilari and compare them with the tadpoles of other species in the Hypsiboas pulchellus group. The description of the tadpole of H. aguilari is based on an individual at Gosner Stage 29 and that of H. melanopleura on an individual at Gosner Stage 28. Both tadpoles have a labial tooth row formula of 2(2)/4(1). At Stage 35, the tadpole of H. aguilari had a total length of 52.2 mm, at Stage 37, the tadpole of H. melanopleura had a total length of 60.7 mm. In life, the tadpole of H. aguilari …


Molecular Anatomy Of The Developing Limb In The Coqu ́I Frog, Eleutherodactylus Coqui, Joshua Gross, Ryan Kerney, James Hanken, Clifford Tabin Dec 2010

Molecular Anatomy Of The Developing Limb In The Coqu ́I Frog, Eleutherodactylus Coqui, Joshua Gross, Ryan Kerney, James Hanken, Clifford Tabin

Ryan Kerney

The vertebrate limb demonstrates remark- able similarity in basic organization across phylogenetically disparate groups. To gain further insight into how this mor- phological similarity is maintained in different developmental contexts, we explored the molecular anatomy of size-reduced embryos of the Puerto Rican coqu ́ı frog, Eleutherodactylus coqui. This animal demonstrates direct development, a life- history strategy marked by rapid progression from egg to adult and absence of a free-living, aquatic larva. Nonethe- less, coqu ́ı exhibits a basal anuran limb structure, with four toes on the forelimb and five toes on the hind limb. We in- vestigated the extent to …


Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney Dec 2010

Levels Of Biological Organization And The Origin Of Novelty, Brian Hall, Ryan Kerney

Ryan Kerney

The concept of novelty in evolutionary biology pertains to multiple tiers of biological organization from behavioral and morphological changes to changes at the molecular level. Identifying novel features requires assessments of similarity (homology and homoplasy) of relationships (phylogenetic history) and of shared developmental and genetic pathways or networks. After a brief discussion of how novelty is used in recent literature, we discuss whether the evolutionary approach to homology and homoplasy initially formulated by Lankester in the 19th century informs our understanding of novelty today. We then discuss six examples of morphological features described in the recent literature as novelties, and …


Embryonic Staging Table For A Direct- Developing Salamander, Plethodon Cinereus (Plethodontidae), Ryan Kerney Dec 2010

Embryonic Staging Table For A Direct- Developing Salamander, Plethodon Cinereus (Plethodontidae), Ryan Kerney

Ryan Kerney

This work presents a refined staging table for the direct-developing red-backed salamander Plethodon cinereus, which is based on the incom- plete staging system of James Norman Dent (J Morphol 1942; 71:577– 601). This common species from eastern North America is a member of the species-rich lungless salamander family Plethodontidae. The stag- ing table presented here covers several stages omitted by Dent and reveals novel developmental features of P. cinereus embryos. These include putative Leydig cells and open gill clefts, which are found in lar- vae of metamorphosing species but were previously reported as absent in direct-developing Plethodon. Other features found …


Are Species Cohesive?—A View From Bacteriology, Frederick M. Cohan Dec 2010

Are Species Cohesive?—A View From Bacteriology, Frederick M. Cohan

Frederick M. Cohan

No abstract provided.


Q&A: Frederick Cohan Dec 2010

Q&A: Frederick Cohan

Frederick M. Cohan

No abstract provided.


Batrachochytrium Dendrobatidis And The Collapse Of Anuran Species Richness And Abundance In The Upper Manu National Park, Southeastern Peru, Edgar Lehr, Allessandro Catenazzi, Lily Rodriguez, Vance Vrendeburg Dec 2009

Batrachochytrium Dendrobatidis And The Collapse Of Anuran Species Richness And Abundance In The Upper Manu National Park, Southeastern Peru, Edgar Lehr, Allessandro Catenazzi, Lily Rodriguez, Vance Vrendeburg

Edgar Lehr

Amphibians are declining worldwide, but these declines have been particularly dramatic in tropical mountains, where high endemism and vulnerability to an introduced fungal pathogen, Batrachochytrium dendrobatidis (Bd), is associated with amphibian extinctions. We surveyed frogs in the Peruvian Andes in montane forests along a steep elevational gradient (1200-3700 m). We used visual encounter surveys to sample stream-dwelling and arboreal species and leaf-litter plots to sample terrestrial-breeding species. We compared species richness and abundance among the wet seasons of 1999, 2008, and 2009. Despite similar sampling effort among years, the number of species (46 in 1999) declined by 47% between 1999 …


Batrachochytrium Dendrobatidis In The Live Frog Trade Of Telmatobius (Anura: Ceratophryidae) In The Tropical Andes, Edgar Lehr, Alessandro Catenazzi, Vance Vredenburg Dec 2009

Batrachochytrium Dendrobatidis In The Live Frog Trade Of Telmatobius (Anura: Ceratophryidae) In The Tropical Andes, Edgar Lehr, Alessandro Catenazzi, Vance Vredenburg

Edgar Lehr

Species of frogs in the genus Telmatobius are traded and sold for human consumption in the Andes and in coastal cities of Peru and Bolivia. These frogs are harvested from wild populations. We report high prevalence of infection by the pathogenic fungus Batrachochytrium dendrobatidis in live frogs purchased at the main market in Cusco, Peru, from January 2008 to January 2010. We suggest that the transport of native anurans through the live frog trade could facilitate the spread of this fungus among Andean frogs. The tropical Andes are the most important biodiversity hotspot for amphibians. Because many neotropical taxa are …


A New Andean Species Of The Hypsiboas Pulchellus Group: Adults, Calls, And Phylogenetic Relationships, Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer Dec 2009

A New Andean Species Of The Hypsiboas Pulchellus Group: Adults, Calls, And Phylogenetic Relationships, Edgar Lehr, Julian Faivovich, Karl-Heinz Jungfer

Edgar Lehr

We describe a new species of the Hypsiboas pulchellus Group from the eastern Andes of central Peru (Region Pasco). Calls of both H. melanopleura and the new species are described. The new species is more similar to H. melanopleura and H. palaestes but differs in morphological characters and in coloration pattern. The new species and H. melanopleura are included in a molecular phylogenetic analysis of the H. pulchellus Group that shows them to be sister species and forming a second, independent, Andean clade within the group. New collecting sites for H. melanopleura are provided with the first record in the …


Two New Species Of Bryophryne (Anura: Strabomantidae) From High Elevations In Southern Peru (Region Of Cusco), Edgar Lehr, Alessandro Catenazzi Dec 2009

Two New Species Of Bryophryne (Anura: Strabomantidae) From High Elevations In Southern Peru (Region Of Cusco), Edgar Lehr, Alessandro Catenazzi

Edgar Lehr

We describe two new species of Bryophryne from the Region of Cusco, Provincia de La Convencio´n in southern Peru, increasing the number of currently known Bryophryne to eight. One of the new species is the second known species of Bryophryne that has a tympanic annulus and tympanic membrane. Males of this species have vocal slits, a vocal sac, and call from inside moss. It is readily distinguished from all its congeners by having a blackish-brown venter with yellow, orange, or pale pink blotches. This species is found at elevations of 3800–3850 m in the puna along the road from Vilcabamba …


Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan Kerney, Brian K. Hall, James Hanken Dec 2009

Regulatory Elements Of Xenopus Col2a1 Drive Cartilaginous Gene Expression In Transgenic Frogs, Ryan Kerney, Brian K. Hall, James Hanken

Ryan Kerney

This study characterizes regulatory elements of collagen 2α1 (col2a1) in Xenopus that enable transgene expression in cartilage-forming chondrocytes. The reporters described in this study drive strong cartilage-specific gene expression, which will be a valuable tool for further investigations of Xenopus skeletal development. While endogenous col2a1 mRNA is expressed in many embryonic tissues, its expression becomes restricted to tadpole and adult chondrocytes. This chondrocyte-specific expression is recapitulated by col2a1 reporter constructs, which were tested through I-SceI meganuclease-mediated transgenesis. These constructs contain a portion of the Xenopus tropicalis col2a1 intron, which aligns to a cartilage-specific intronic enhancer that has been well characterized …


New Species Of Pristimantis (Anura: Strabomantidae) From The Amazonian Lowlands Of Southern Peru, Edgar Lehr, Rudolf Von May Dec 2008

New Species Of Pristimantis (Anura: Strabomantidae) From The Amazonian Lowlands Of Southern Peru, Edgar Lehr, Rudolf Von May

Edgar Lehr

We describe a new species of Pristimantis from the Amazonian lowlands in southern Peru (Madre de Dios Region). The new species has a snout–vent length of 22.8–23.4 mm in two adult males (females are unknown), a tympanum barely visible, a W-shaped scapular ridge, the iris bearing a dark vertical bar forming a cross or a T, a cream venter with brown blotches, and groin and concealed surfaces of shanks with a contrasting pattern consisting of yellow and black. It is tentatively assigned to the unistrigatus species Group and is most similar to Pristimantis diadematus and Pristimantis eurydactylus.