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Full-Text Articles in Life Sciences

Characterizing New Plant Fossils With Woody Growth From The Battery Point Formation Of Quebec (Canada), Emma T. Casselman Jan 2024

Characterizing New Plant Fossils With Woody Growth From The Battery Point Formation Of Quebec (Canada), Emma T. Casselman

Cal Poly Humboldt theses and projects

The oldest woody growth has been recognized in several Early Devonian (ca. 410-395 Ma) euphyllophytes. Their taxonomic diversity is difficult to evaluate due to a lack of quantitative methods for comparing plants based on secondary xylem anatomy. In turn, this hinders understanding of their implications for the evolution of plant development. To develop metrics that quantify secondary xylem anatomy and allow for conclusive comparisons, I investigated extant taxa and Early Devonian fossil woody taxa. I developed multiple metrics for quantifying tracheid size as a function of position in the secondary xylem and tested them on a dataset of extant gymnosperms. …


Diversity And Distribution Of Bryozoans Of The Northern To Central Rocky Outer Coast Of California, Ismael Chowdhury Jan 2023

Diversity And Distribution Of Bryozoans Of The Northern To Central Rocky Outer Coast Of California, Ismael Chowdhury

Cal Poly Humboldt theses and projects

The phylum Bryozoa is one of the most diverse groups of marine invertebrates, with a global distribution that spans marine and fresh waters. This study analyzes the Bryozoa in infralittoral communities on rocky surfaces from northern California (Point Saint George) to central California (Estero Bay), spanning 940 kilometers and encompassing 12 rocky intertidal sites. Although recent studies on bryozoan taxonomy and phylogeny have increased due to scanning electron microscopy (SEM) and high throughput sequencing, there is still a lack of studies on species found in shallow waters at intertidal depths, particularly in the northeastern Pacific. This study aims to expand …


Systematics Of Amanita (Amanitaceae, Agaricales, Basidiomycota) From The Guiana Shield And Central Africa, Kennan S. Mighell Jan 2020

Systematics Of Amanita (Amanitaceae, Agaricales, Basidiomycota) From The Guiana Shield And Central Africa, Kennan S. Mighell

Cal Poly Humboldt theses and projects

This study is a systematic assessment of ten species of ectomycorrhizal fungi of the genus Amanita (Amanitaceae, Agaricales, Basidiomycota) from the lowland tropical rainforests of the Guiana Shield and Central Africa. Fungi were collected in each of the above regions, analyzed morphologically, and compared to the literature on Amanita diversity worldwide. All species addressed herein are given full formal taxonomic descriptions including complete macro- and microscopic character profiles, habit, habitat, and distribution. Phylogenetic assessments using ribosomal DNA and protein coding genes are provided for Guiana Shield taxa, and sequence data for two non-protein coding regions, the …


The Bee Fauna Of The Horse Mountain And Grouse Mountain Region, Humboldt County, California, Carrie Lopez Jan 2017

The Bee Fauna Of The Horse Mountain And Grouse Mountain Region, Humboldt County, California, Carrie Lopez

Cal Poly Humboldt theses and projects

Recent concerns about the ecological well-being of bee communities in California and elsewhere have increased the need for monitoring programs and studies that evaluate the impact of habitat loss and alteration on bee diversity and abundance. Such studies depend critically on the expertise of people trained in taxonomy, but their numbers have declined in recent years. My primary goal was to gain a comprehensive first-hand experience with bee identification by documenting the fauna of a previously unstudied area in the mountains of northwestern California and by writing an identification key, intended for dedicated non-specialists, to the area’s 35 species of …