Evolution Commons^™

Reproductive Isolation In The Elegans-Group Of Caenorhabditis, Scott Everet Baird, Sara Rose Seibert

Biological Sciences Faculty Publications

Reproductive isolation is the basis of the Biological Species Definition and can be a driving force of speciation. Theoretical studies have provided models of how reproductive isolation can arise within individual species. Genetic tests of these models are limited to populations in which reproductive isolation is present but not complete. Here, reproductive isolation in the Elgans-Group of the nematode genus Caenorhabditis is reviewed. Pre-mating barriers, assortative fertilization and post-zygotic barriers all have been observed in this clade. In some combinations of species, fertile F1 hybrids can be obtained. Therefore, the Elegans-Group of Caenorhabditis is poised to become an important experimental …

A Comparison Of Relative Ear Length Between Two Neighboring Populations Of Peromyscus Maniculatus, Joshua S. Willems

Biological Sciences

This study attempts to determine if a significant difference in relative ear length exists between two neighboring populations of Peromyscus maniculatus on the central coast of California. Data was collected from individuals trapped at two plots in the Guadalupe-Nipomo Dunes National Wildlife Refuge and two plots near Black Lake, under the supervision of Francis X. Villablanca, Ph. D. of California Polytechnic State University, San Luis Obispo. A total of 98 individuals were captured over the course of three nights of trapping. A regression analysis was performed comparing the ear lengths of each population relative to body size. The analysis of …

Landscape Genetics Of Leaf-Toed Geckos In The Tropical Dry Forest Of Northern Mexico, Christopher Blair, Victor H. Jimenez-Arcos, Fausto R. Mendez De La Cruz, Robert W. Murphy

Publications and Research

Habitat fragmentation due to both natural and anthropogenic forces continues to threaten the evolution and maintenance of biological diversity. This is of particular concern in tropical regions that are experiencing elevated rates of habitat loss. Although less well-studied than tropical rain forests, tropical dry forests (TDF) contain an enormous diversity of species and continue to be threatened by anthropogenic activities including grazing and agriculture. However, little is known about the processes that shape genetic connectivity in species inhabiting TDF ecosystems. We adopt a landscape genetic approach to understanding functional connectivity for leaf-toed geckos (Phyllodactylus tuberculosus) at multiple sites …

Attitudes Toward Evolution At New England Colleges And Universities, United States, Guillermo Paz-Y-Miño-C, Avelina Espinosa

New England Science Public: Series Evolution

Paz-y-Miño-C G & Espinosa A. 2013. Attitudes toward Evolution at New England Colleges and Universities, United States. New England Science Public: Series Evolution 1(1): 1-32 (ISSN: 2326-0971). We compile the most significant results of our conceptual and quantitative studies on the patterns of acceptance of evolution at New England colleges and universities, conducted between 2009 and 2012. We examine the views of New England Faculty and Educators of Prospective Teachers (higher-education faculty themselves, specialized in training future teachers) from 35 colleges and universities, as well as a representative sample of College Students from a Public, Private and two Religious …

Assessing Regional And Interspecific Variation In Threshold Responses Of Forest Breeding Birds Through Broad Scale Analyses, Yntze Van Der Hoek, Rosalind Renfrew, Lisa L. Manne

Publications and Research

Background: Identifying persistence and extinction thresholds in species-habitat relationships is a major focal point of ecological research and conservation. However, one major concern regarding the incorporation of threshold analyses in conservation is the lack of knowledge on the generality and transferability of results across species and regions. We present a multi-region, multi-species approach of modeling threshold responses, which we use to investigate whether threshold effects are similar across species and regions.

Methodology/Principal Findings: We modeled local persistence and extinction dynamics of 25 forest-associated breeding birds based on detection/non-detection data, which were derived from repeated breeding bird atlases for the state …

(Review) Deep History: The Architecture Of Past And Present, Frederick S. Paxton

History Faculty Publications

The article reviews the book "Deep History: The Architecture of Past and Present," edited by Andrew Shryock and Daniel Lord Smail.

Recently Described Vulture One Of Several New Avian Species From The Ashfall Fossil Beds, Rick E. Otto

University of Nebraska State Museum: Programs Information

Several species of fossil bird are known from the Ashfall Fossil Beds. As of publication date, all represent previously undescribed species. In 2012, ornithologists Zhang, Feduccia and James described a vulture from isolated remains recovered from the Ashfall site in 1979. Similar in morphology to the Palm-nut Vulture (Gypohierax) of Africa, the relationship to the Ashfall vulture is unclear, and may represent an example of convergent evolution. The fossil vulture was designated Anchigyps voorhiesiin honor of paleontologist Michael Voorhies.

Tree Climbing And Human Evolution, Vivek V. Venkataraman, Thomas S. Kraft, Nathaniel J. Dominy

Dartmouth Scholarship

Paleoanthropologists have long argued—often contentiously—about the climbing abilities of early hominins and whether a foot adapted to terrestrial bipedalism constrained regular access to trees. However, some modern humans climb tall trees routinely in pursuit of honey, fruit, and game, often without the aid of tools or support systems. Mortality and morbidity associated with facultative arboreality is expected to favor behaviors and anatomies that facilitate safe and efficient climbing. Here we show that Twa hunter–gatherers use extraordinary ankle dorsiflexion (>45°) during climbing, similar to the degree observed in wild chimpanzees. Although we did not detect a skeletal signature of dorsiflexion …

Filling In The Gaps In Phenology And Life History Of The Cumberland Plateau Salamander (Plethodon Kentucki), Robert C. Bowers

Theses, Dissertations and Capstones

The Cumberland Plateau Salamander, Plethodon kentucki, is a member of the Plethodon glutinosus complex comprising 16 sibling species, which are best differentiated by range. Few studies have been conducted to gain information on the natural history of P. kentucki. To alleviate this, two sites at Beech Fork State Park in Wayne County, West Virginia were used to study the salamander’s general life history with emphasis on reproduction, phenology, and population size. At each site, three 20m x 20m sample plots were arranged based on viability of the habitat for P. kentucki. Ground searches of all cover objects …

Nietzsche And Darwin, Babette Babich

Working Papers

Abstract

I argue against the popular view of Nietzsche as Darwinist and I concur with other Nietzsche scholars who have also noted that other authors worked in Nietzsche’s thinking in association with Darwin, not only Spencer and Malthus but also Roux and Haeckel among others which also for Nietzsche included Empedocles and other ancient scientists. Nietzsche offers plain condemnation of Darwin’s views but he is also often associated with Darwin owing to Darwin’s racism and his own vision of rank-order. I conclude with an emphasis on style and Nietzsche’s reading of antiquity to highlight the distinction he sought to make …

A Further Look At The 1858 Wallace-Darwin Mail Delivery Question, Charles H. Smith

DLPS Faculty Publications

Recent investigations have led to a conclusion that Alfred Russel Wallace probably mailed his ‘Ternate’ paper on natural selection to Darwin a month later than some have thought, thus freeing Darwin from possible accusations of plagiarism. Further examination of the question suggests this conclusion is premature, as the evidence in favor of the later mailing date appears to be shakier than first thought.

Dietary Preference Of The Queensnake (Regina Septemvittata), Timothy J. Brust

Theses, Dissertations and Capstones

The Queensnake (Regina septemvittata) is a small secretive water snake found throughout the eastern United States. Once common, their numbers have declined to the extent that they are now threatened throughout most of their range, largely the result of pollutant-based reduction in prey species. These snakes are assumed to eat molted crayfish exclusively. For some common crayfish species, molting happens only twice a summer during a two- week period. It has not been documented if Queensnakes eat anything besides crayfish on a regular basis. The purpose of this study was to determine the prey preference of Queensnakes with particular focus …

Euryhalinity In An Evolutionary Context, Eric T. Schultz, Stephen D. Mccormick

EEB Articles

This chapter focuses on the evolutionary importance and taxonomic distribution of euryhalinity. Euryhalinity refers to broad halotolerance and broad halohabitat distribution. Salinity exposure experiments have demonstrated that species vary tenfold in their range of tolerable salinity levels, primarily because of differences in upper limits. Halotolerance breadth varies with the species’ evolutionary history, as represented by its ordinal classification, and with the species’ halohabitat. Freshwater and seawater species tolerate brackish water; their empirically-determined fundamental haloniche is broader than their realized haloniche, as revealed by the halohabitats they occupy. With respect to halohabitat distribution, a minority of species (<10%) are euryhaline. Habitat-euryhalinity is prevalent among basal actinopterygian fishes, is largely absent from orders arising from intermediate nodes, and reappears in the most derived taxa. There is pronounced family-level variability in the tendency to be halohabitat-euryhaline, which may have arisen during a burst of diversification following the Cretaceous-Palaeogene extinction. Low prevalence notwithstanding, euryhaline species are potent sources of evolutionary diversity. Euryhalinity is regarded as a key innovation trait whose evolution enables exploitation of new adaptive zone, triggering cladogenesis. We review phylogenetically-informed studies that demonstrate freshwater species diversifying from euryhaline ancestors through processes such as landlocking. These studies indicate that some euryhaline taxa are particularly susceptible to changes in halohabitat and subsequent diversification, and some geographic regions have been hotspots for transitions to freshwater. Comparative studies on mechanisms among multiple taxa and at multiple levels of biological integration are needed to clarify evolutionary pathways to, and from, euryhalinity.

Direct And Indirect Selection On Floral Pigmentation By Pollinators And Seed Predators In A Color Polymorphic South African Shrub, Jane E. Carlson, Kent E. Holsinger

EEB Articles

The coexistence of different color morphs is often attributed to variable selection pressures across space, time, morph frequencies or selection agents, but the routes by which each morph is favored are rarely identified. In this study we untangle the interactions and trait pleiotropisms that influence floral color polymorphisms on a local scale in Protea, within which ~40% of species are polymorphic. Previous work shows that seed predators and reproductive differences likely influence polymorphism maintenance in four Protea species. Here, we explore whether selection acts on floral color directly or indirectly in Protea aurea, using path analysis of pollinator …

To 'Die Hel' And Back. Expeditions Of The Phylogeny Of World Tachinidae Project. Part I: Western Cape, South Africa, Pierfilippo Cerretti, James E. O'Hara, John O. Stireman Iii, Isaac S. Winkler, Ashley H. Kirk-Spriggs

Biological Sciences Faculty Publications

The “Phylogeny of World Tachinidae” project kicked off with an operational meeting in June 2012 at the Canadian National Collection of Insects (CNC) in Ottawa. Goals were discussed, work plans prepared, and of course the destinations and timing of major field expeditions were debated. During our three years of National Science Foundation funding we hope to gather fresh material for molecular analysis from all biogeographic regions of the world.

A Path To Success? A Review Of Evolution, Development, And The Predictable Genome By David L. Stern, Hope Hollocher, Charles H. Pence, Grant Ramsey, Michelle M. Wirth

Faculty Publications

No abstract provided.

Evolution Of The Human Diet: What We Can Learn From Hunters And Gatherers, Kara Osborne, Alyssa Crittenden

McNair Poster Presentations

The study of hunter-gatherer populations around the world can greatly inform our understanding of the evolution of the human diet. Ethnographic research of modern hunter-gatherers has been used to infer the possible food consump­tion and acquisition patterns of our ancestors. Hunter-gatherers provide the in­formation necessary for the understanding of the past human diet, due to these populations living similar lifestyles in similar environments, therefore procuring similar foods.

The Hadza, a group of nomadic hunters and gatherers living in Tanzania, East Africa, are one of the primary populations that nutritional anthropologists study to infer what possible foods our ancestors acquired and …

Staffan Müller-Wille And Hans-Jörg Rheinberger, A Cultural History Of Heredity, Charles H. Pence

Faculty Publications

No abstract provided.

Developmental Adaptation Hypothesis : Aerobic Capacity, Submaximal Arterial Saturation And Pulmonary Volumes In Peruvian Quechua Natives, Melisa Kiyamu Tsuchiya

Legacy Theses & Dissertations (2009 - 2024)

The Quechua populations have inhabited the Andes for hundreds of generations. The ability to thrive in this hostile environment, leading an active and healthy life has generated research questions about the special phenotype of Andean highlanders compared to their sea-level counterparts, such as their higher pulmonary volumes and their outstanding work capacity in spite of the challenge of oxygen transport and delivery in hypoxia. In high altitude natives, there have been two main explanations for the origins of the aforementioned traits: genetic adaptation through natural selection and developmental adaptation through the exposure to hypoxia during growth.

The Causes And Consequences Of Individual Variation In Parental Care Behavior, Daniel P. Wetzel

Theses and Dissertations--Biology

Behavioral traits can be remarkably flexible depending on the conditions in which they are expressed, yet, in spite of this flexibility, persistent differences between individuals appear to limit the potential expression of behaviors. For example, despite evidence that parents provide variable amounts of parental care in response to changing environmental conditions, they also differ in the overall level of care they provide. I used a behavioral reaction norm approach to study individual variation in parental care behavior in free-living house sparrows (Passer domesticus). I investigated the nature of this variation by studying the relationship between different forms of …