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Full-Text Articles in Life Sciences

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters Jul 2014

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters

Benjamin F. Dattilo

Olivella columellaris (Sowerby 1825) and O. semistriata (Gray 1839) are suspension feeding, swash surfing snails on tropical sandy beaches of the east Pacific. While they often are the numerically dominant macrofaunal element in their habitats, their biology is poorly understood; the two species actually have been confused in all of the few publications that address their ecology. Frequent misidentifications in publications and collections contributed also to an overestimation of the geographic overlap of the two species. To provide a sound taxonomic basis for further functional, ecological, and evolutionary investigations, we evaluated the validity of diagnostic traits in wild populations and …


Genetics, Behavior And Ecology Of A Paper Wasp Invasion: Polistes Dominulus In North America, Aviva Liebert Dec 2012

Genetics, Behavior And Ecology Of A Paper Wasp Invasion: Polistes Dominulus In North America, Aviva Liebert

Aviva E Liebert

Studies of social insect invasions to date have focused primarily on highly eusocial insects such as ants and yellowjacket wasps. Yet insect societies without fixed, morphological caste systems may be particularly good invaders due to their behavioral flexibility, as demonstrated by the recent invasion of the European paper wasp Polistes dominulus into North America. Here we provide a review of this ongoing invasion in terms of (1) population genetic variation in P. dominulus, and (2) comparative behavior and ecology of P. dominulus vs. the native P. fuscatus. We present new genetic evidence supporting the occurrence of multiple independent introductions of …


Patterns Of Life History And Habitat Use Of An Important Recreational Fishery Species, Spotfin Croaker, And Their Potential Fishery Implications, Jonathan Williams, Jeremy Claisse, Daniel Pondella, Lea Medeiros, Charles Valle, Michael Shane Nov 2012

Patterns Of Life History And Habitat Use Of An Important Recreational Fishery Species, Spotfin Croaker, And Their Potential Fishery Implications, Jonathan Williams, Jeremy Claisse, Daniel Pondella, Lea Medeiros, Charles Valle, Michael Shane

Daniel Pondella

Spotfin croakers Roncador stearnsii, a prized recreational catch, were collected throughout the Southern California Bight, primarily as bycatch from a long-term, scientific gill-net collection effort. The maximum otolith-based age in the present study was 24 years—14 years greater than in a previous scale-based aging study. Multiple models were used to estimate mean length at age, including models that utilize larvae as well as juveniles and adults, and the model selection results suggest sexual dimorphism in growth patterns. The juvenile and adult catch per unit effort reflected a clear pattern of habitat selectivity, with fish strongly preferring soft-bottom habitats. Catches …


El Niño Periods Increase Growth Of Juvenile White Seabass (Atractoscion Nobilis) In The Southern California Bight, Jonathan Williams, Larry Allen, Mark Steele, Daniel Pondella Nov 2012

El Niño Periods Increase Growth Of Juvenile White Seabass (Atractoscion Nobilis) In The Southern California Bight, Jonathan Williams, Larry Allen, Mark Steele, Daniel Pondella

Daniel Pondella

Studies of the impact of El Niño periods on marine species have usually focused on negative, highly visible eVects, e.g., decreasing growth rates or increasing mortality due to a decline in primary productivity in typically nutrient rich upwelling zones; but positive effects related to elevated water temperature are also known. This study examined how the growth rate of juvenile white seabass, Atractoscion nobilis, responded to changes in ocean temperature in an El Niño period (1997–1998) in the northern portion of the Southern California Bight, USA. Growth rates of juvenile white seabass during their first 4 years of life were …


Life History, Ecology, And Long-Term Demographics Of Queenfish, Eric Miller, Jonathan Williams, Daniel Pondella, Kevin Herbinson Nov 2012

Life History, Ecology, And Long-Term Demographics Of Queenfish, Eric Miller, Jonathan Williams, Daniel Pondella, Kevin Herbinson

Daniel Pondella

Queenfish Seriphus politus were collected at coastal power plants from San Clemente to Ventura, California. Power functions best described relations between otolith length, width, or weight and either standard length (SL) or total body weight. The length–weight relationship was described by the following equation: weight 1⁄4 10􏰀5 3 SL3.09. Individuals were aged to 12 years by using sagittal otolith sections. Females grew at a significantly faster rate than males. Both sexes reached 50% maturity by 100 mm SL, or shortly after age 1. The total annual instantaneous mortality coefficient was estimated at 0.42. Catalina Harbor (on the windward side of …


Catalogue Of Type Material In The Entomological Collection Of The University Of La Laguna (Canary Islands). I – Arachnida, Ana Reboleira, Antonio Pérez, Nuria Macías-Hernandez, Heriberto López, S. De La Cruz, Pedro Oromí Oct 2012

Catalogue Of Type Material In The Entomological Collection Of The University Of La Laguna (Canary Islands). I – Arachnida, Ana Reboleira, Antonio Pérez, Nuria Macías-Hernandez, Heriberto López, S. De La Cruz, Pedro Oromí

Ana Sofia P.S. Reboleira

A catalogue of arachnid type specimens of the collection kept at the Department of Animal Biology, University of La Laguna (Spain) is presented. It harbours type material of 104 species belonging to 23 families of arachnids, represented by 21 holotypes and 164 paratypes for 23 species of pseudoscorpions, and 49 holotypes, 218 paratypes and 3 syntypes for 81 species of spiders. This collection is using the criteria and standards of the Global Biodiversity Information Facility (GBIF) for cataloguing and computerization of the specimens. Type specimens were checked with the original descriptions, and relevant additional information from original labels not included …


Lusoblothrus, A New Syarinid Pseudoscorpion Genus (Arachnida) From Portugal, Occupying An Isolated Position Within The Holarctic Fauna, Ana Reboleira, Juan Zaragoza, Fernando Gonçalves, Pedro Oromí Oct 2012

Lusoblothrus, A New Syarinid Pseudoscorpion Genus (Arachnida) From Portugal, Occupying An Isolated Position Within The Holarctic Fauna, Ana Reboleira, Juan Zaragoza, Fernando Gonçalves, Pedro Oromí

Ana Sofia P.S. Reboleira

The new pseudoscorpion genus Lusoblothrus of the family Syarinidae is described from a cave in the Algarve region, southern Portugal, to accommodate L. aenigmaticus sp. nov., whose morphological affinities within the Holarctic syarinid fauna are not clear and resembles the Gondwanan genera. This discovery emphasizes the relevance of the Algarve region as a hotspot for relictual hypogean fauna within the Iberian Peninsula.


Compilation, Calibration, And Synthesis Of Faunal And Floral Radiocarbon Dates, Rancho La Brea, California, F. O’Keefe, Elizabeth Fet, John Harris Sep 2012

Compilation, Calibration, And Synthesis Of Faunal And Floral Radiocarbon Dates, Rancho La Brea, California, F. O’Keefe, Elizabeth Fet, John Harris

F. Robin O’Keefe

This paper presents a compilation and synthesis of calibrated radiocarbon dates for the Rancho La Brea tar pits, Los Angeles, California. A literature survey yielded 188 dates, and 21 additional dates are presented here for the first time. These range in age from 185 to 50,000 radiocarbon years. Dating of Rancho La Brea fossils has been uneven; only from Pits 91 and 2051 have more than 30 dates been obtained. The depositional history of well-sampled pits was complex, with one or more episodes of major accumulation interspersed with lower background levels of entrapment. The most significant quantifiable source of error …


What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters Jun 2012

What Can We Learn From Confusing Olivella Columellaris And O. Semistriata, Two Key Species In Panamic Sandy Beach Ecosystems?, Alison Troost, Samantha Rupert, Ariel Cyrus, Frank Paladino, Benjamin Dattilo, Winfried Peters

Winfried S. Peters

Olivella columellaris (Sowerby 1825) and O. semistriata (Gray 1839) are suspension feeding, swash surfing snails on tropical sandy beaches of the east Pacific. While they often are the numerically dominant macrofaunal element in their habitats, their biology is poorly understood; the two species actually have been confused in all of the few publications that address their ecology. Frequent misidentifications in publications and collections contributed also to an overestimation of the geographic overlap of the two species. To provide a sound taxonomic basis for further functional, ecological, and evolutionary investigations, we evaluated the validity of diagnostic traits in wild populations and …


Extreme Environments Select For Reproductive Assurance: Evidence From Evening Primroses (Oenothera), Margaret Evans, David Hearn, Kathryn Theiss, Karen Cranston, Kent Holsinger, Michael Donoghue Jun 2012

Extreme Environments Select For Reproductive Assurance: Evidence From Evening Primroses (Oenothera), Margaret Evans, David Hearn, Kathryn Theiss, Karen Cranston, Kent Holsinger, Michael Donoghue

Kent E Holsinger

• Competing evolutionary forces shape plant breeding systems (e.g. inbreeding depression, reproductive assurance). Which of these forces prevails in a given population or species is predicted to depend upon such factors as life history, eco- logical conditions, and geographical context. Here, we examined two such predictions: that self-compatibility should be associated with the annual life history or extreme climatic conditions.

• We analyzed data from a clade of plants remarkable for variation in breeding system, life history and climatic conditions (Oenothera, sections Anogra and Kleinia, Onagraceae). We used a phylogenetic comparative approach and Bayesian or hybrid Bayesian tests to account …


Comparing Volunteer And Professionally Collected Monitoring Data From The Rocky Subtidal Reefs Of Southern California, Usa, David Gillett, Daniel Pondella, Jan Freiwald, Kenneth Schiff, Jennifer Caselle, Craig Shuman, Stephen Weisberg Apr 2012

Comparing Volunteer And Professionally Collected Monitoring Data From The Rocky Subtidal Reefs Of Southern California, Usa, David Gillett, Daniel Pondella, Jan Freiwald, Kenneth Schiff, Jennifer Caselle, Craig Shuman, Stephen Weisberg

Daniel Pondella

Volunteer-based citizen monitoring has increasingly become part of the natural resources monitoring framework, but it is often unclear whether the data quality from these programs is sufficient for integration with traditional efforts conducted by professional scientists. At present, the biological and physical characteristics of California’s rocky reef kelp forests are concurrently monitored by two such groups, using similar methodologies—underwater visual census (UVC) of fish, benthic invertebrates, and reef habitat, though the volunteer group limits their sampling to transects close to the reef surface and they use a more constrained list of species for enumeration and measurement. Here, we compared the …


Squamatinia Algharbica Gen. N. Sp. N., A Remarkable New Coletiniinae Silverfish (Zygentoma: Nicoletiidae) From Caves In Southern Portugal, Ana Reboleira, Fernando Gonçalves, Pedro Oromí, Luís Mendes Mar 2012

Squamatinia Algharbica Gen. N. Sp. N., A Remarkable New Coletiniinae Silverfish (Zygentoma: Nicoletiidae) From Caves In Southern Portugal, Ana Reboleira, Fernando Gonçalves, Pedro Oromí, Luís Mendes

Ana Sofia P.S. Reboleira

A new genus of Coletiniinae silverfish (Nicoletiidae) similar to Coletinia Wygodzinsky and Lepidospora Escherich is described to accommodate the new species Squamatinia algharbica gen. n. sp. n. Many individuals were collected over all seasons of the year in four caves of the Algarve karst massif in the south of Portugal. An identification key for the known genera of Coletiniinae is provided, as well as some biogeographical and ecological comments.


The Behavioural And Sensory Ecology Of Agaronia Propatula (Caenogastropoda, Olividae), A Swash-Surfing Predator On Sandy Beaches Of The Panamic Faunal Province, Ariel Cyrus, Samantha Rupert, Amy Silva, Monika Graf, Jeremy Rappaport, Frank Paladino, Winfried Peters Mar 2012

The Behavioural And Sensory Ecology Of Agaronia Propatula (Caenogastropoda, Olividae), A Swash-Surfing Predator On Sandy Beaches Of The Panamic Faunal Province, Ariel Cyrus, Samantha Rupert, Amy Silva, Monika Graf, Jeremy Rappaport, Frank Paladino, Winfried Peters

Winfried S. Peters

The genus Agaronia includes dominant predators in the eulittoral zone of dissipative sandy beaches of the tropical Eastern Pacific, which show specific adaptations to this environment such as swash-surfing locomotion. We studied A. propatula in its natural habitat in El Salvador and Costa Rica, and performed field experiments to obtain insights into its ecology, behaviour and sensory physiology. Agaronia propatula is not attracted by carrion and preys mostly on the ubiquitous beach snail Olivella semistriata. This, however, reflects community composition rather than prey specialization; A. propatula is an investigative hunter and will, quite literally, attack everything that moves (with …


Global Patterns Of Leaf Mechanical Properties, Yusuke Onoda, Mark Westoby, Peter Adler, Amy Choong, Fiona Clissold, Johannes Cornelissen, Sandra Díaz, Nathaniel Dominy, Alison Elgart, Lucas Enrico, Paul Fine, Jerome Howard, Adel Jalili, Kaoru Kitajima, Hiroko Kurokawa, Clare Mcarthur, Peter Lucas, Lars Markesteijn, Natalia Pérez-Harguindeguy, Lourens Poorter, Lora Richards, Louis Santiago, Enio Sosinski, Sunshine Van Bael, David Warton, Ian Wright, S. Wright, Nayuta Yamashita Mar 2012

Global Patterns Of Leaf Mechanical Properties, Yusuke Onoda, Mark Westoby, Peter Adler, Amy Choong, Fiona Clissold, Johannes Cornelissen, Sandra Díaz, Nathaniel Dominy, Alison Elgart, Lucas Enrico, Paul Fine, Jerome Howard, Adel Jalili, Kaoru Kitajima, Hiroko Kurokawa, Clare Mcarthur, Peter Lucas, Lars Markesteijn, Natalia Pérez-Harguindeguy, Lourens Poorter, Lora Richards, Louis Santiago, Enio Sosinski, Sunshine Van Bael, David Warton, Ian Wright, S. Wright, Nayuta Yamashita

Jerome J. Howard

Leaf mechanical properties strongly influence leaf lifespan, plant–herbivore interactions, litter decomposition and nutrient cycling, but global patterns in their interspecific variation and underlying mechanisms remain poorly understood. We synthesize data across the three major measurement methods, permitting the first global analyses of leaf mechanics and associated traits, for 2819 species from 90 sites worldwide. Key measures of leaf mechanical resistance varied c. 500–800-fold among species. Contrary to a long-standing hypothesis, tropical leaves were not mechanically more resistant than temperate leaves. Leaf mechanical resistance was modestly related to rainfall and local light environment. By partitioning leaf mechanical resistance into three different …


On Characterizing Adaptive Events Unique To Modern Humans, Jessica Crisci, Alex Wong, Jeffrey Good, Jeffrey Jensen Feb 2012

On Characterizing Adaptive Events Unique To Modern Humans, Jessica Crisci, Alex Wong, Jeffrey Good, Jeffrey Jensen

Jessica L Crisci

Ever since the first draft of the human genome was completed in 2001 there has been increased interest in identifying genetic changes that are uniquely human, which could account for our distinct morphological and cognitive capabilities with respect to other apes. Recently, draft sequences of two extinct hominin genomes, a Neanderthal and Denisovan, have been released. These two genomes provide a much greater resolution to identify human-specific genetic differences than the chimpanzee, our closest extant relative. The Neanderthal genome paper presented a list of regions putatively targeted by positive selection around the time of the human-Neanderthal split. We here seek …


Occurrence And Biological Effect Of Exogenous Steroids In The Elkhorn River, Nebraska, Usa, Alan Kolok, Daniel Snow, Satomi Kohno, Marlo Sellin, Louis Guillette Feb 2012

Occurrence And Biological Effect Of Exogenous Steroids In The Elkhorn River, Nebraska, Usa, Alan Kolok, Daniel Snow, Satomi Kohno, Marlo Sellin, Louis Guillette

Daniel D Snow

Recent studies of surface waters in North America, Japan, and Europe have reported the presence of steroidogenic agents as contaminants. The current study has three objectives: 1) to determine if steroidogenic compounds are present in the Elkhorn River, 2) to determine if sediments collected from the Elkhorn River can act as a source of steroidogenic compounds to aquatic organisms, and 3) to determine if site-specific biological effects are apparent in the hepatic gene expression of fathead minnows. Evidence was obtained using three approaches: 1) deployment of polar organic chemical integrative samplers (POCIS), 2) deployment of caged fathead minnows, and 3) …


Competition For Aphid Prey Between Different Lady Beetle Species In A Laboratory Arena, Christy Leppanen, Andrei Alyokhin, Serena Gross Dec 2011

Competition For Aphid Prey Between Different Lady Beetle Species In A Laboratory Arena, Christy Leppanen, Andrei Alyokhin, Serena Gross

Andrei Alyokhin

Direct competition for aphid prey (Hemiptera: Aphididae) was evaluated between and among several lady beetle species (Coleoptera: Coccinellidae). The behavior of three native (Coccinella trifasciata, Coleomegilla maculata, and Hippodamia convergens) and four nonnative (Coccinella septempunctata, Harmonia axyridis, Hippodamia variegata, and Propylea quatuordecimpunctata) lady beetles was observed in laboratory arenas. The beetles were kept alone, paired with conspecifics or paired with heterospecifics, and presented with potato aphids (Macrosiphum euphorbiae). Harmonia axyridis was the most successful aphid predator in our study, being able to find aphids more quickly and consume more of them compared to most other lady beetle species. It was …


Recent Progress In Polymorphism-Based Population Genetic Inference., Jessica Crisci, Yu-Ping Poh, Angela Bean, Alfred Simkin, Jeffrey Jensen Dec 2011

Recent Progress In Polymorphism-Based Population Genetic Inference., Jessica Crisci, Yu-Ping Poh, Angela Bean, Alfred Simkin, Jeffrey Jensen

Jessica L Crisci

The recent availability of whole-genome sequencing data affords tremendous power for statistical inference. With this, there has been great interest in the development of polymorphism-based approaches for the estimation of population genetic parameters. These approaches seek to estimate, for example, recently fixed or sweeping beneficial mutations, the rate of recurrent positive selection, the distribution of selection coefficients, and the demographic history of the population. Yet despite estimating similar parameters using similar data sets, results between methodologies are far from consistent. We here summarize the current state of the field, compare existing approaches, and attempt to reconcile emerging discrepancies. We also …


Do Larval Traits Re-Evolve? Evidence From The Embryogenesis Of A Direct-Developing Salamander, Plethodon Cinereus, Ryan Kerney, David Blackburn, Hendrik Muller, James Hanken Dec 2011

Do Larval Traits Re-Evolve? Evidence From The Embryogenesis Of A Direct-Developing Salamander, Plethodon Cinereus, Ryan Kerney, David Blackburn, Hendrik Muller, James Hanken

Ryan Kerney

Recent molecular phylogenies suggest the surprising reacquisition of posthatching metamorphosis within an otherwise directdeveloping clade of lungless salamanders (family Plethodontidae). Metamorphosis was long regarded as plesiomorphic for plethodontids, yet the genus Desmognathus, which primarily includes metamorphosing species, is now nested within a much larger clade of direct-developing species. The extent to which the putative reacquisition of metamorphosis in Desmognathus represents a true evolutionary reversal is contingent upon the extent to which both larva-specific features and metamorphosis were actually lost during the evolution of direct development. In this study we analyze development of the hyobranchial skeleton, which is dramatically remodeled during …


Allometry And Growth, Andrew Kerkhoff Dec 2011

Allometry And Growth, Andrew Kerkhoff

Andrew J Kerkhoff

No abstract provided.


Microtopographic Heterogeneity Constrains Alpine Plant Diversity, Glacier National Park, Mt, George Malanson, Jonathan Rose Dec 2011

Microtopographic Heterogeneity Constrains Alpine Plant Diversity, Glacier National Park, Mt, George Malanson, Jonathan Rose

George P Malanson

Theoretical and empirical evidence exists for a postive relationship between environmental heterogeneity and species diversity. Contrary to our expectations, microtopographic heterogeneity does not promote the diversity of alpine plants.