Front cover image for How many fossils, how to count them, and where to collect them : examinations of the most appropriate methods for community paleoecological research

How many fossils, how to count them, and where to collect them : examinations of the most appropriate methods for community paleoecological research

Paleoecology researchers have employed an array of methods for collecting, counting, and identifying fossil data; no standard protocol exists for conducting community paleoecological research. The lack of a standard protocol could lead to inaccurate conclusions. In addition, paleocommunity research is labor- and time-intensive, as it requires expertise in multiple taxonomic groups and geological sub-disciplines. Therefore, it is important not to over-sample (individuals per sample or number of total samples), because an increasingly large sample size and number of samples will eventually result in diminishing returns in terms of improving any pattern revealed by the data. Resources should be allocated appropriately to learn as much as possible about the Earth's history. Here, I examined (1) the spatial and temporal resolution of fossil sample collection, (2) the counting methods most appropriate for community paleoecological research (abundance or biomass), (3) the groups of fossil organisms that should be examined in order to gain an accurate picture of past ecosystems, (4) the taxonomic level of identification, and (5) sample size (number of individual fossil specimens collected per sample). The ultimate goal of this research is to provide a set of "best" or most accurate methods for use in community paleoecological research. I found that a sample size of 50 is sufficient for community paleoecological research that employs multivariate statistical techniques. This value is supported more definitively when using fossils (30 datasets), but is still supported using 44 modern datasets. In addition, I demonstrate that fewer lateral samples are required when conducting community paleoecological research at relatively greater temporal scales. These data could potentially allow researchers to save time and money. Research efforts and resources can be focused gaining a greater number of samples per study or conducting additional studies. There are areas where greater paleontological resources should be allocated. (1) Genus (or species) identification is required for an accurate representation of paleocommunities. (2) Whenever possible, researchers should tally the abundance of fossil taxa in concert with a biomass proxy (i.e., point counts). (3) In addition, researchers should examine all available taxa, as opposed to single taxonomic groups, such as only brachiopods
Thesis, Dissertation, English, ©2013
University of Alberta
1 online resource ([6], 143 pages) : illustrations, maps
"A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Earth and Atmospheric Sciences."