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Full-Text Articles in Biology
Constraints Of The Imagination: How Phenotypes Are Shaped Through Genetics, The Environment, And Development, Michelle Gilbert
Constraints Of The Imagination: How Phenotypes Are Shaped Through Genetics, The Environment, And Development, Michelle Gilbert
Doctoral Dissertations
Phenotypic constraints are ubiquitous throughout nature, being found throughout all stages of life and at multiple different biological levels including cellular, genetic, environmental, behavioral, evolutionary, and developmental. These constraints have shaped, not only the natural world, but the way that we perceive what is possible, or impossible, an observation made clear by François Jacob in his 1977 paper “Evolution and Tinkering”. This is reflected in the literature, repeatedly, by the regular occurrence of densely packed visualization of phenotypic space that seemingly always have large areas that go unoccupied. Despite constrained regions of space being observable across countless taxa, identifying the …
The Role Of Phenotypic Integration In Mammalian Tooth Function And Jaw Morphological Diversity, Andrew Conith
The Role Of Phenotypic Integration In Mammalian Tooth Function And Jaw Morphological Diversity, Andrew Conith
Doctoral Dissertations
Here I investigate how two major components of the mammalian feeding system, teeth and jaws, are influenced by functional, environment, and developmental factors. First, I build physical models of the molars from two early mammals, Morganucodon and Kuehneotherium, and compare their ability to process a proxy food item. Early mammals were under strong selection to reduce metabolic costs, so any savings in energy during feeding would be advantageous. I tested the ability of both mammals to process a hard and soft food item with material properties similar to that of the insects they would have likely consumed. Morganucodon was …
Spider Brain Morphology & Behavior, Skye M. Long
Spider Brain Morphology & Behavior, Skye M. Long
Doctoral Dissertations
Spiders are ideal model animals for experimental and comparative studies of behavior, learning and perception. They display many complex behaviors, such as the multimodal mating dances of lycosid spiders, the stealthy hunting strategies of the jumping spider Portia sp., to the labile sociality of theridiids. Spiders also demonstrate a wide range of cognitive capabilities. Spiders perceive their environment using multiple sensory modalities including: chemosensory organs; lyriform and slit-sense organs and specialized hairs that detect vibration and air movement; and up to eight eyes that vary in function, some able to detect polarization and a broad spectrum of light, including …