Evolution Commons^™

Axolotl Paedomorphosis: A Comparison Of Juvenile, Metamorphic, And Paedomorphic Ambystoma Mexicanum Brain Gene Transcription, Carlena Johnson

Theses and Dissertations--Biology

Unlike many amphibians, the paedomorphic axolotl (Ambystoma mexicanum) rarely undergoes external morphological changes indicative of metamorphosis. However, internally, some axolotl tissues undergo cryptic metamorphic changes. A previous study examined interspecific patterns of larval brain gene expression and found that these species exhibited unique temporal expression patterns that were hypothesized to be morph specific. This thesis tested this hypothesis by examining differences in brain gene expression between juvenile (JUV), paedomorphic (PAED), and metamorphic (MET) axolotls. I identified 828 genes that were expressed differently between JUV, PAED, and MET. Expression estimates from JUV were compared to estimates from PAED and …

Insight Into Human Brain Evolution Through Phylogenetic Analysis And Comparative Genomics, Amy Marie Boddy

Wayne State University Dissertations

As a species, humans are often considered to be unique among mammals, with respect to their large brain size and enhanced cognitive abilities. Humans are the most encephalized mammals, with a brain that is six times larger than expected relative to body mass. Presumably, it is this high degree of encephalization that underlies our advanced cognitive abilities, including the skills needed for complex language and culture. Understanding how large brains evolved can shed light on what makes the human brain unique and introduce possible mechanism for human specific neurodegenerative diseases. This study takes a both a phenotypic and molecular approach …

Platyrrhine Phylogenetics With A Focus On Callitrichine Life History Adaptations, Natalie Mae Jameson

Wayne State University Dissertations

The life history of a species is highly impacted by their reproductive strategy. In my dissertation I address the changing reproductive strategies in callitrichine New World monkeys and their genetic underpinnings using a phylogenetic approach. The necessity for a resolved phylogeny is universal to any comparative genomic study. Here we have constructed a reliable phylogenetic framework from which reproductive strategy could be studied in callitrichines. First, to determine the most recent common ancestor of Anthropoid primates we took a phylogenomic approach, using the publicly available whole genome sequences of 17 mammal species. With high confidence, we determined here that Tarsier …

The Lives Of Others: Social Rationality In Animals, Jeffrey R. Stevens, Andrew J. King

Jeffrey Stevens Publications

Darwin (1871) boldly claimed that humans and other animals differ very little in their cognition; a statement that has raised the ire of many scientists (Bolhuis & Wynne, 2009; Penn, Holyoak, & Povinelli, 2008). Rather than stating this continuity as a fact, we will explore the similarities and differences between humans and animals in the social rationality of their decision making. We find this a fruitful exercise because it can profit researchers of both humans and animals. Our purpose here is to provide an evolutionary background of social rationality: Why do animals attend to the lives of others? To this …

The Real Alfred Russel Wallace: Essays On An Outside-The-Box Thinker, Charles H. Smith

Faculty/Staff Personal Papers

Alfred Russel Wallace (8 January 1823 – 7 November 1913), English polymath and social critic, ranks high on the list of the most interesting characters in the history of science. Nevertheless, and despite a life filled with achievement, he has often been marginalized in the halls of learning. The truth is, Wallace was something of an “outside–the–box” thinker, and his many forays into the murkier areas of science and social science cost him a lot of potential supporters. Still others, while recognizing his intellectual talents in general, have looked at the full span of his work and interests as a …

Genetic Diversity In Populations Of Epiphanes Chihuahuaensis (Rotifera: Monogononta) In The Northern Chihuahuan Desert, Diego E. Reyes

Open Access Theses & Dissertations

1. Cryptic speciation in zooplankton is a phenomenon that has been recently gaining much attention. This is due in part to advances in molecular techniques which help in the identification of morphologically indistinct species. Organisms that have been traditionally believed to have cosmopolitan distributions are being found to be composed of cryptic species complexes with high levels of genetic divergence among lineages.

2. Epiphanes chihuahuaensis is a member in the Epiphanes senta species complex. In a previous study by Schröder & Walsh (2007), genetic data, along with morphological and reproductive isolation data were employed to help delineate four species within …

Comparison Of Ectoparasitic Mite Loads Between Gonochoristic (Aspidoscelis Marmorata) And Parthenogenic (A. Tesselata) Syntopic Whiptail Lizards (Teiidae) From The Northern Chihuahuan Desert Of Trans-Pecos, Texas, William Dawson Lukefahr

Open Access Theses & Dissertations

The objective of this study was to compare the ectoparasitic loads between two syntopic whiptail lizard species (Teiidae) that differ in their reproductive modes; Aspidoscelis marmorata (bisexual) and A. tesselata (unisexual). The study site was located on Indio Mountains Research Station (IMRS) in a Chihuahuan Desert Scrub landscape in Hudspeth County, Texas. Previous studies conducted at IMRS showed the two species having similar diets, morphology, and reproductive characteristics, but fluctuated in nematode loads. No comparative study of ecotoparasitic mites (Eutrombicula alfreddugesi) between the two species has ever been done.

Aspidoscelis marmorata (n = 141) and A. tesselata (n = 144) …

Family Matters: An Analysis Of Genetic Relatedness Of Tetraclita Rubescens (The Pink Volcano Barnacle) Over Several Spatial Scales At Monterey And Bodega Bay, California, Kelly N. Chang

Scripps Senior Theses

Inbreeding involves the mating of closely related individuals at a higher frequency than at random; this can decrease the average fitness of populations and individuals by reducing the presence of heterozygotes and augmenting the expression of deleterious genes. Since marine invertebrates exhibit widespread dispersal, their potential for inbreeding is often disregarded. The adult sessile state of barnacles creates the potential for inbreeding as a result of necessary copulation between neighboring individuals. Depending on the degree of mixing that occurs during dispersal, closely related individuals or siblings may settle in close proximity, generating the possibility of kin aggregation and consequent inbreeding. …

The Physiology Of Invasive Plants In Low-Resource Environments, Jennifer L. Funk

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

While invasive plant species primarily occur in disturbed, high-resource environments, many species have invaded ecosystems characterized by low nutrient, water, and light availability. Species adapted to low-resource systems often display traits associated with resource conservation, such as slow growth, high tissue longevity, and resource-use efficiency. This contrasts with our general understanding of invasive species physiology derived primarily from studies in high-resource environments. These studies suggest that invasive species succeed through high resource acquisition. This review examines physiological and morphological traits of native and invasive species in low-resource environments. Existing data support the idea that species invading low-resource environments possess traits …

Five New Species Of Chaerilus Simon, 1877 From China, Indonesia, Malaysia, Philippines, Thailand, And Vietnam (Scorpiones: Chaerilidae), František Kovařík

Euscorpius

Chaerilus cimrmani sp. n. from Thailand, C. seiteri sp. n. from Philippines (Negros Island), C. solegladi sp. n. from Indonesia and Malaysia (Borneo Island), C. terueli sp. n. from Vietnam (Côn Son Island), and C. wrzecionkoi sp. n. from China (Tibet) are described. A key to all species of the genus Chaerilus Simon, 1877 is also presented.

Three New Species Of Compsobuthus Vachon, 1949 From Yemen, Jordan, Israel, And Somaliland (Scorpiones: Buthidae), František Kovařík

Euscorpius

Compsobuthus krali sp. n. of the werneri group from Yemen, C. levyi sp. n. of the werneri group from Jordan and Israel, and C. somalilandus sp. n. of the acutecarinatus group from Somaliland are described. A key to all species of the genus Compsobuthus Vachon, 1949 is presented.

Phenotypic Plasticity Of Oral Jaw Dentition In Archosargus Probatocephalus, Cynthia E. Worcester

Masters Theses & Specialist Projects

Phenotypic plasticity, the capacity of a single genotype to exhibit variable phenotypes in different environments, is common in many species. A sample of wild caught Archosargus probatocephalus, also known as sheepshead, from Florida was randomly divided into two treatment groups: one group was fed soft prey, Mercenaria sp. muscle tissue, and the other group was fed hard prey, Mercenaria sp. in the shell, for 365 days. It was hypothesized that the sheepshead fed hard prey would have a thicker tooth enamel layer containing more calcium, and therefore be stronger than the tooth enamel layer of those fed soft prey …

Winter Microhabitat Foraging Preferences Of Sympatric Boreal And Black-Capped Chickadees In Michigan's Upper Peninsula, Alec R. Lindsay Ph. D., Zach G. Gayk

Faculty Works

We examined differences in microhab- itat use between Boreal (Poecile hudsonicus) and Black- capped chickadees (P. atricapillus) where they co-occur near Marquette, Michigan, USA. Twenty-four Boreal and 37 Black-capped chickadees were followed during 60 hrs of field observation. Boreal Chickadees foraged only in three conifer species, 76% of which were black spruce (Picea mariana), while Black-capped Chickadees foraged widely across six coniferous and three deciduous tree species. Analysis of foraging data categorized by zones within conifer trees indicated high niche overlap (0.676) between Boreal and Black-capped chickadees across all foraging zones. Individual comparisons on a zone-by-zone basis revealed a significant …

The Fall Of "Augustinian Adam": Original Fragility And Supralapsarian Purpose, John Schneider

University Faculty Publications and Creative Works

This essay is framed by conflict between Christianity and Darwinian science over the history of the world and the nature of original human personhood. Evolutionary science narrates a long prehuman geological and biological history filled with vast amounts, kinds, and distributions of apparently random brutal and pointless suffering. It has also unveiled an original human person with animal psychosomatic heredity. This narrative seems to discredit Christianity's (Augustinian) metanarrative of the Fall-Paradise Lost and Paradise Regained. The author contends that the Augustinian story and its character of Adam are implausible, anyway, for reasons of theology and apologetics. He proposes that Christians …

Gene Duplication And The Evolution Of Hemoglobin Isoform Differentiation In Birds, Michael T. Grispo

School of Biological Sciences: Dissertations, Theses, and Student Research

The majority of bird species co-express two functionally distinct hemoglobin (Hb) isoforms in definitive erythrocytes: HbA (the major adult Hb isoform, with α-chain subunits encoded by the α^A-globin gene) and HbD (the minor adult Hb isoform, with α-chain subunits encoded by the α^D-globin gene). The α^D-globin gene originated via tandem duplication of an embryonic α-like globin gene in the stem lineage of tetrapod vertebrates, which suggests the possibility that functional differentiation between the HbA and HbD isoforms may be attributable to a retained ancestral character state in HbD that harkens back to a primordial, …

Phenotypic Plasticity Of Rattlesnake Trophic Morphology, Matthew Thomas Smith

Graduate Theses and Dissertations

The trophic morphology of gape-limited predators constrains the shape and size of prey items they can ingest. Trophic morphology consists of any morphological feature that is involved in the handling and ingestion of food. Diet has a profound effect on the morphology of many gape-limited predators. Identifying how prey type and resource level affect the morphology of different populations is an essential step in understanding the mechanisms contributing to patterns of morphological diversity. Species interactions (Chapter 1) induce plasticity in morphology that can lead to increased fitness, morphological divergence, and eventually speciation.

In Chapter 2, a laboratory study tested the …

The Role Of Olfactory Cues In The Sequential Radiation Of A Gall-Boring Beetle, Mordellistena Convicta, Bradley Rhodes, Catherine Blair, Mizuki Takahashi, Warren G. Abrahamson Ii

Faculty Journal Articles

1. Herbivorous insects often have close associations with specific host plants, and their preferences for mating and ovipositing on a specific host-plant species can reproductively isolate populations, facilitating ecological speciation. Volatile emissions from host plants can play a major role in assisting herbivores to locate their natal host plants and thus facilitate assortative mating and host-specific oviposition.

2. The present study investigated the role of host-plant volatiles in host fidelity and oviposition preference of the gall-boring, inquiline beetle, Mordellistena convicta LeConte (Coleoptera: Mordellidae), using Y-tube olfactometers. Previous studies suggest that the gall-boring beetle is undergoing sequential host-associated divergence by utilising …

Aspm And The Evolution Of Cerebral Cortical Size In A Community Of New World Monkeys, Fernando A. Villanea, George H. Perry, Gustavo A. Gutiérrez-Espeleta, Nathaniel J. Dominy

Dartmouth Scholarship

The ASPM (abnormal spindle-like microcephaly associated) gene has been proposed as a major determinant of cerebral cortical size among primates, including humans. Yet the specific functions of ASPM and its connection to human intelligence remain controversial. This debate is limited in part by a taxonomic focus on Old World monkeys and apes. Here we expand the comparative context of ASPM sequence analyses with a study of New World monkeys, a radiation of primates in which enlarged brain size has evolved in parallel in spider monkeys (genus Ateles) and capuchins (genus Cebus). The primate community of Costa Rica is perhaps a …

Euscorpius Sicanus (Scorpiones: Euscorpiidae) From Tunisia: Dna Barcoding Confirms Ancient Disjunctions Across The Mediterranean Sea, Matthew R. Graham, Pavel Stoev, Nesrine Akkari, Gergin Blagoev, Victor Fet

Biological Sciences Faculty Research

We used a DNA barcoding marker (mitochondrial cox1) to investigate the controversial natural occurrence of Euscorpius sicanus (C.L. Koch) in North Africa. We tested this hypothesis by comparing a sample collected from a mountain in Tunisia to disjunct populations in Sardinia, Malta, and Greece. Using these samples, and a few additional Euscorpius spp. from southern Europe as outgroups, we reconstructed the maternal phylogeny. We then used a molecular clock to place the phylogeny in a temporal context. The Tunisian sample grouped closest to a specimen from Sardinia, with both being more distantly related to E. sicanus from Malta, which is …

Estimates Of Body Mass For Fossil Giant Ground Squirrels, Genus Paenemarmota, H. Thomas Goodwin, Kelsey M. Bullock

Faculty Publications

Paenemarmota Hibbard and Schultz, 1948 includes 3 species of giant ground squirrels within Marmotini (Rodentia, Sciuridae) from the Late Miocene and Pliocene of central and western North America. We developed skeletal and dental models for estimating body mass across modern species of Marmotini and apply these models to Paenemarmota. The most reliable models for estimating body mass of modern species (on the basis of length and width of femur, lengths of p4 and P4) generally yielded lower estimates of body mass for Paenemarmota than less reliable models (on the basis of lengths of m1, m2, M1, and M2). Models that …