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Full-Text Articles in Life Sciences

Predators As Agents Of Selection And Diversification, Jerald B. Johnson, Mark C. Belk Oct 2020

Predators As Agents Of Selection And Diversification, Jerald B. Johnson, Mark C. Belk

Faculty Publications

Predation is ubiquitous in nature and can be an important component of both ecological and evolutionary interactions. One of the most striking features of predators is how often they cause evolutionary diversification in natural systems. Here, we review several ways that this can occur, exploring empirical evidence and suggesting promising areas for future work. We also introduce several papers recently accepted in Diversity that demonstrate just how important and varied predation can be as an agent of natural selection. We conclude that there is still much to be done in this field, especially in areas where multiple predator species prey …


Biotic Filtering In Endophytic Fungal Communities, Kevin Daniel Ricks Jun 2018

Biotic Filtering In Endophytic Fungal Communities, Kevin Daniel Ricks

Theses and Dissertations

Plants can be colonized by complex communities of endophytic fungi. This thesis presents two studies, both of which investigate biotic filtering in endophytic fungal communities. Chapter 1. Endophytic fungi can be acquired horizontally via propagules produced in the environment such as in plant litters of various species. Given that litters from different plant species harbor distinct endophytic fungal communities and that endophytic fungi may be dispersal-limited, the structure of the endophytic fungal community of a given plant may be determined by proximity to particular inoculum sources. Community assembly may also be affected by biotic filtering by the plant. Therefore, a …


Interaction Between Predation Environment And Diet Constrains Body Shape In Utah Chub, Gila Atraria (Cypriniformes: Cyprinidae), Trevor J. Williams, Jerald B. Johnson, Mark C. Belk Jun 2017

Interaction Between Predation Environment And Diet Constrains Body Shape In Utah Chub, Gila Atraria (Cypriniformes: Cyprinidae), Trevor J. Williams, Jerald B. Johnson, Mark C. Belk

Faculty Publications

Evolution typically occurs in response to a suite of selective pressures. Yet, many studies of natural selection in the wild only investigate a single selective agent at a time. This can be problematic when selective agents act in non-additive ways. Here we evaluate the interactive effects of diet and predation on the evolution of body shape in the cyprinid fish Utah chub (Gila atraria). We found that both factors and the interaction between them are significant predictors of body shape. This interaction is likely a result of different forms of selective pressures, where predation is a stabilizing selective …


Natural Selection In Samoan Metabolic Pathways, Sage Wright, John Kauwe Mar 2017

Natural Selection In Samoan Metabolic Pathways, Sage Wright, John Kauwe

Journal of Undergraduate Research

One of the leading causes of death in Pacific Islanders is diabetes or other metabolic diseases [cdc]. This may be due to the idea that the thrifty genotype hypothesis contributes to the increase in type 2 diabetes [Southam]. The thrifty genotype hypothesis suggests that certain genes that encourage an increase in body fat were beneficial for our ancestors in times of famine. During periods where food was plentiful, these genes would act so that they would deposit fat in order to better survive during famines. It allows individuals to store nutrients that they would need when food was no longer …


Repeated Trait Evolution Driven By Divergent Natural Selection At Early And Late Stages Of Speciation, Spencer J. Ingley Oct 2015

Repeated Trait Evolution Driven By Divergent Natural Selection At Early And Late Stages Of Speciation, Spencer J. Ingley

Theses and Dissertations

Speciation – the process by which new species arise – is of fundamental importance in the biological sciences. The means by which new species arise, and the relationship among living species, has been a topic that has captivated both lay and scientific observers for centuries. In recent years, the study of speciation has enjoyed increased attention, resulting in significant advances in our understanding of how species form. Although our understanding of the processes that contribute to speciation has increased dramatically in recent years, our knowledge of how reproductive barriers accumulate as speciation proceeds is still limited. Thus, studies that evaluate …


Morphological Divergence Driven By Predation Environment Within And Between Species Of Brachyrhaphis Fishes, Spencer J. Ingley, Eric J. Billman, Mark C. Belk, Jerald B. Johnson Feb 2014

Morphological Divergence Driven By Predation Environment Within And Between Species Of Brachyrhaphis Fishes, Spencer J. Ingley, Eric J. Billman, Mark C. Belk, Jerald B. Johnson

Faculty Publications

Natural selection often results in profound differences in body shape among populations from divergent selective environments. Predation is a well-studied driver of divergence, with predators having a strong effect on the evolution of prey body shape, especially for traits related to escape behavior. Comparative studies, both at the population level and between species, show that the presence or absence of predators can alter prey morphology. Although this pattern is well documented in various species or population pairs, few studies have tested for similar patterns of body shape evolution at multiple stages of divergence within a taxonomic group. Here, we examine …


Prevalence Of Teleological And Lamarckian Misconceptions Of Natural Selection Among College Students, Bryce T. Battisti Aug 2004

Prevalence Of Teleological And Lamarckian Misconceptions Of Natural Selection Among College Students, Bryce T. Battisti

Theses and Dissertations

Science teachers and researchers note that students must correctly understand the role of natural selection in evolution to make sense of biology. The level of understanding of natural selection can be assessed using the Conceptual Inventory of Natural Selection (CINS) which is a 20-item multiple-choice test that incorporates student misconceptions as distractors. In the present study, Item Response Theory (IRT) was used to analyze the occurance of misconceptions on the CINS among 1192 students in an introductory non-majors biology course. The four most difficult topics in the CINS are: (a) how change occurs in a population; (b) origin of variation; …