Graduation Date
Spring 2018
Document Type
Thesis
Program
Master of Science degree with a major in Biology
Committee Chair Name
Alexandru Tomescu
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
Michael Mesler
Second Committee Member Affiliation
HSU Faculty or Staff
Third Committee Member Name
Gar Rothwell
Third Committee Member Affiliation
Community Member or Outside Professional
Fourth Committee Member Name
Ignacio Escapa
Fourth Committee Member Affiliation
Community Member or Outside Professional
Subject Categories
Botany
Abstract
Diverse in modern ecosystems, mosses are dramatically underrepresented in the fossil record. Furthermore, most pre-Cenozoic mosses are known only from compression fossils, which lack detailed anatomical information. Lower Cretaceous deposits at Apple Bay (Vancouver Island, British Columbia, Canada) contain a diverse anatomically preserved flora that includes numerous bryophytes, many of which have yet to be characterized. Among them is a polytrichaceous moss that is described here as Meantoinea alophosioides gen. et sp. nov. Meantoinea alophosioides represents the first occurrence of gemma cups in a fossil moss and is the oldest unequivocal record of Polytrichaceae, providing a hard minimum age for the group of 136 Ma (Valanginian). In order to assess the phylogenetic relationships of fossil Polytrichaceae (including Meantoinea) and compare hypotheses of relationships recovered using molecular vs morphological methods, I conducted a comprehensive morphology-based phylogenetic study of the family. This phylogenetic study used a dataset of 100 morphological characters scored for 44 species of acrocarpous mosses, and parsimony as the optimality criterion. Results of the phylogenetic analysis suggest that morphology is useful in resolving phylogenetic relationships in the Polytrichaceae and that both fossil Polytrichaceae have stable phylogenetic relationships. However, rooting experiments demonstrate that there is no superior way to root analyses and indicate that relationships within the family are best evaluated using unrooted networks without outgroup taxa. These rooting problems suggest that additional information is needed to understand the phylogenetic relationships of Polytrichaceae. Such additional information could come from fossils of stem group polytrichaceous mosses, which await discovery.
Citation Style
American Journal of Botany
Recommended Citation
Bippus, Alexander C., "Extending the fossil record of the Polytrichaceae (Bryophyta): insights from the early Cretaceous of Vancouver Island, Canada" (2018). Cal Poly Humboldt theses and projects. 134.
https://digitalcommons.humboldt.edu/etd/134