Ecology and Evolutionary Biology Commons^™

Electrosensory Ampullary Organs Are Derived From Lateral Line Placodes In Bony Fishes, Melissa S. Modrell, William E. Benis, R. Glenn Northcutt, Marcus C. Davis, Clare V.H. Baker

Faculty and Research Publications

Electroreception is an ancient subdivision of the lateral line sensory system, found in all major vertebrate groups (though lost in frogs, amniotes and most ray-finned fishes). Electroreception is mediated by 'hair cells' in ampullary organs, distributed in fields flanking lines of mechanosensory hair cell-containing neuromasts that detect local water movement. Neuromasts, and afferent neurons for both neuromasts and ampullary organs, develop from lateral line placodes. Although ampullary organs in the axolotl (a representative of the lobe-finned clade of bony fishes) are lateral line placode-derived, non-placodal origins have been proposed for electroreceptors in other taxa. Here we show morphological and molecular …

A Mathematician Weighs In On The Evolution Debate, Kris H. Green

Journal of Humanistic Mathematics

There are a variety of reasons underlying the lack of public acceptance for the theory of evolution in the United States. An overlooked cause is related to problems with the mathematics curriculum in the K-12 setting. In this essay, we examine this relationship and propose changes to the mathematics curriculum that could improve mathematical thinking while also providing a basis for understanding theories, like evolution, that are poorly understood.

Determining The Composition Of The Dwelling Tubes Of Antarctic Pterobranchs, Lukasz J. Sewera

Honors Projects

Pterobranchs are a group of marine invertebrates within the Hemichordata, which share characteristics with both chordates and echinoderms. Pterobranchs live in colonies of secreted tubes, coenicia, which are composed of a gelatinous material of unknown composition. Visually, the tubes appear similar to the tunic of tunicates, a group of invertebrates within the Chordata. The nonproteinaceous tunic of tunicates is composed of cellulose, which is unusual. The goal of this study was to determine the composition of the pterobranch coenicium. Some aspects of pterobranch phylogeny are still unclear even after multiple molecular and morphological studies. Identification of any new shared characteristics …

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

EEB Articles

• 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 …

Using Google Earth To Teach The Magnitude Of Deep Time, Joel D. Parker

Joel D Parker

Most timeline analogies of geologic and evolutionary time are fundamentally flawed. They trade off the problem of grasping very long times for the problem of grasping very short distances. The result is an understanding of relative time with little comprehension of absolute time. Earlier work has shown that the distances most easily understood by teachers and students are those most people can experience directly. Thus most timeline analogies are flawed by either overcompressing an experienceable time or relying on an unexperienceable distance. Under the constraint of experienceability, the best timeline to distance scale must be at least 75 miles and …

The Importance Of Disease And Behavior In Mammalian Ecology And Behavior, Christopher R. Collins

Legacy Theses & Dissertations (2009 - 2024)

Causes of mortality reflect the evolutionary forces shaping the physiology and behavior of species. To evaluate the relative importance of these in North American Mammals I compared published data from 69 populations across 27 species. Of the known causes, humans are the main cause of mortality (51.8%), followed by natural causes (48.5%), with predation being the largest natural cause. Populations in remote areas experienced higher hunting mortality, and those closer to human populations suffered increased vehicle collision. Predation mortality was negatively correlated with body mass.

Darwin's Other Idea : Sexual Selection, Gender And Violence, Robert Samuel Moschgat

Legacy Theses & Dissertations (2009 - 2024)

This dissertation provides an empirical exploration of Darwin's theory of sexual selection, which views the male propensity to engage in short term mating strategies--sexual promiscuity and violence--as the result of sexual selection. Within an environmental context, biological father and mother household presence are expected to inhibit the initiation of short-term mating strategies and increase parental investment--paternal and maternal attachments, supervision, and protection. Whereas, structural disadvantage--living in poverty and in dangerous neighborhoods--is predicted to increase the initiation of a short-term mating strategies and compromise the parents' ability to protect their children and by weakening paternal and maternal attachments, thereby increasing the …

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 …