Mike Barker
barkerms@muohio.edu

Education:
B.S. Biology, Denison University, Granville, Ohio, 2001.
M.S. Botany, Miami University, Oxford, Ohio, 2001


Current Research:
At present, my research interests are the systematics, taxonomy, speciation processes, population biology, biogeography, and general biology of pteridophytes (the ferns and their allies).

 


Mike collecting in the woods
Pteridophytes possess a rich and fascinating evolutionary history that has produced a group of organisms with unique evolutionary processes and patterns. In many areas of pteridology we are still identifying and sorting out taxa, and we are only beginning to understand the evolutionary forces that operate and have operated in this distinct group of plants. I hope that my research elucidates some of these evolutionary patterns and can contribute to a better understanding of pteridophyte systematics.

My current master's research focusses on the cheilanthoid fern genus Adiantopsis. This genus of about 9 species occurs in tropical America and possibly Africa. Adiantopsis has been relatively unstudied and the taxonomic placement of the group has been debated over the last 150 years. Some members of the genus resemble members of Adiantum (hence Adiantopsis), however most do not. Currently, the genus is considered to be most closely related to Cheilanthes, although the relationship is not well understood. Adiantopsis is distinguished from other cheilanthoid genera by possessing echinate spores, adaxial ridges along the rachis and costae, and assymetrical ultimate segments.

In my current research, I am examing the origin of A. pedata (Hook.) Moore, a species endemic to Cuba, Jamaica, and Hispanola. During March 2001, R. J. Hickey collected plants resembling A. pedata in Argentina. A few other collections of this A. pedata - like plant have been made over the past 100 years from Argentina, Paraguay, and Brazil. The main goal of my research is to use a combination of morphological and cytological data to determine if these plants from Argentina are indeed A. pedata. As a component of this research, I am testing hypotheses for the origin of A. pedata which include allopolyploid, allohomoploid, and divergent speciation mechanisms. Through this methodology, I hope to determine if these plants share a common origin, or if they are two geographically and evolutionary separate taxa.


Previous Research:
For my previous research at Denison University, I studied the systematics of the eusporangiate fern genus Sceptridium (Botrychium subg. Sceptridium; Ophioglossaceae) with Warren D. Hauk. Specifically, I studied the genetic distinctness of S. dissectum var. dissectum and S. dissectum var. obliquum using ISSR markers. The two taxa have been variously described as forms, varieties, or not formerly recognized over the past century. My ISSR results demonstrated that there were no genetic discontinuities that separate the two taxa. In addition, the ISSR data revealed low levels of population genetic structure in S. dissectum, and values for the distribution of ISSR genotypes were similar to values obtained from isozyme genotype distributions. Based on a limited number of individuals, the ISSR data also demonstrated no genetic discontinuities between S. dissectum and S. oneidense.

A manuscript describing this research has been submitted to the American Fern Journal, and will hopefully be accepted and published soon. For more information on the ISSR PCR technique I used, feel free to contact me. In the past, I have also used ISSR PCR to examine the population genetic structure of Draba verna L. and I have used RAPD PCR to examine Dutch elm disease tolerant American elm cultivars.