Population genetic structure is widespread in many organisms and can be found at small spatial scales. Fine-scale differentiation is the result of ecological and evolutionary processes working together to produce an overall pattern, but the relative importance of these factors in population differentiation is poorly understood. The goals of my...
An increased understanding of secondary metabolism in fungi is important for both biological and societal reasons. The ascomycete genus, Tolypocladium, is an ideal system to explore secondary metabolism characterization, ecology, evolution and regulation. The genus produces and has the genomic potential to produce a wide array of metabolites. Paired with...
Question: Are there general life-history rules for exploitation-caused extinction of mammal populations?
Mathematical methods: A population of size N faced with the added mortality of human exploitation will deterministically go extinct if its per-capita birth rate can no longer match its per-capita mortality rate as N approaches zero. We develop...
The evolutionary relationship between Frankia and actinorhizal plants was evaluated
by reconstructing molecular phylogenetic trees from nifH, 16S rDNA, and rbcL
nucleotide sequences. Subgroupings in Frankia phylogenetic trees reconstructed from
nifH and from 16S rDNA sequences were consistent in terms of plant origins of Frankia
strains. Although the branching order...
Long-term data sets that quantitatively confirm basic ecological theory are rare for field
populations. Highly variable recruitment often causes wide temporal variation in population
age distribution and basic theory for adaptive sex ratio often predicts ‘sex ratio tracking’ to
match the fluctuating age distribution. Using sex-changing shrimp as a model...
Kelso's theory of Biocultural Evolution states that as culture evolves, the variation between groups diminishes while the variation within groups increases. The theory is tested with stature, cephalic index and nasal index. Means and standard deviations for these traits are examined for 237 ethnic groups. The groups are organized according...
Determination of the Vertebrate pedigree was a
particularly enigmatic problem for evolutionary morphologists
of the early post-Darwinian period. At that time,
practically no characteristics were known by which the
Vertebrates could be linked to any of the other animal
groups. Up to the 1850's, most research in embryology
and anatomy...
Caenorhabditis elegans is arguably the best understood animal on the planet.
Used for over 50 years to study development, we have a vast amount of knowledge of
the inner workings of this worm. Our knowledge is incomplete, however, without
placing this organism in its evolutionary and ecological context. In this...
Rhizopogon vesiculosus is a common ectomycorrhizal (EM) symbiont of Pseudotusga menziesii (Douglas-fir) in the coast range of the Pacific Northwest. The species has been studied for its systematics, genet size, population structure, and competitive ability in several field and experimental studies. This thesis seeks to provide a more thorough characterization...
Hypotheses of phylogenetic and historical zoogeographic relationships of glyptocephalines (Glyptocephalus cynoglossus, G. zachirus, G. stelleri, Microstomus kitt, H. pacificus, H. achne,
Embassichthys bathybius, and Tanakius kitaharae) were constructed based on comparative anatomy and external morphology. The phylogenetic approach was cladistic and character polarity was
determined by using out-group comparison. One...