James G. Harris, Ph.D.
My research over the past two years has focused on the use of molecular
approaches to study phylogenetic and taxonomic relationships in the
circumboreal genus Braya (Cruciferae). I and my students, in a
collaborative project with botanists at the Canadian Department of
Agriculture, the Missouri Botanical Garden, and the University of
Heidelberg, have used DNA sequence data from the Internal Transcribed
Spacer (ITS) region of the nuclear ribosomal DNA and from the trnL region
of the chloroplast genome to infer phylogenetic relationships in Braya
and its relatives. More recently, we are using sequence-specific PCR
primers to provide evidence of a relatively recent hybrid origin of some
In addition, I´m pursuing floristic studies in Utah with emphases on
high elevation areas, particularly those in the Great Basin, and on cliff
Renée Van Buren, Ph.D.
My research interests are in the rare plant biology of plants of Utah and
surrounding areas. Our studies include habitat characterization, population
characteristics, demographic monitoring, and reproductive biology. Our most
recent taxa of interest include Astragalus holmgreniorum, A. ampullarioides,
and Arctomecon humilis, which are all narrow endemics of the southwest region
of Washington Co., Utah. Voucher specimens are collected and deposited in
the UVSC herbarium for the rare species of interest and of species identified
as associates of the target species' habitat. We are also interested in
understanding the impacts of introduced exotics on the rare native plants.
Conservation and managment strategies are a part of our research as
information becomes available concerning these taxa and their contribution to
the biodiversity of the planet.
Flora of the Mojave Desert and Great Basin
Molecular Systematics of Restricted Endemics
Jason A. Alexander, Ph.D.
The following is a summary of my current research on the molecular systematics of rare endemics in the Mojave Desert and Great Basin:
North America, a region with over 400 species of Astragalus, is one of three major centers of
diversity, all of which comprise the majority of the nearly 1750 species of Astragalus worldwide.
One of the most diverse species, Astragalus lentiginosus of Section Diphysi, is a
polymorphic complex of over 40 varieties, ranging from the West Coast to Texas and the
Rocky Mountains. Over half of these varieties are endemic to the Intermountain States of Utah, Nevada and
The Palantia was a sectional name within the genus
Tium used by Per Axel Rydberg for taxa formerly reduced by Marcus E. Jones to
varieties of Astragalus lentiginosus, all of which have cylindrical pods that,
unlike the majority of the remaining varieties, do not become bladdery inflated upon maturity.
The Palantia, in a modern interpretation, consists of A. lentiginosus var. mokiacensis and A. lentiginosus var. bryantii
(traditionally delimited at the species level) plus the scarcely inflated varieties of A. lentiginosus, primarily A. lentiginosus var. maricopae,
A. lentiginosus var. palans, A. lentiginosus var. ursinus, and A. lentiginosus var.
Taxa in the Palantia range from widespread taxa to narrow
endemics. Astragalus lentiginosus var. palans is the most widespread taxon in this group. It is
composed of many small, local populations spread throughout its range in
Utah, Colorado, and Arizona, with several, disjunct populations along its
margins. Astragalus mokiacensis is an endemic with a narrower range, but
much larger local populations (up to 10,000 individuals).
Astragalus lentiginosus var. ursinus and A. lentiginosus var. maricopae are highly restricted, narrow endemics.
Astragalus lentiginosus var. ursinus is known from four or five populations in the Beaver Dam
Mountains, Mohave County, Arizona and Washington County, Utah. This
species grows exclusively in limestone to sandy limestone talus on mountain
peaks, and can be occasionally be found growing in washes and in limestone
crevices on cliff faces below. Astragalus lentiginosus var. maricopae is currently
found in the alluvial fans northeast of Scottsdale, Maricopa County, Arizona.
Only three, small populations (less than 20 individuals) were relocated in this
study. At least four or five historical populations apparently have been
extirpated due to urbanization. It is likely than the total number of
individuals of A. lentiginosus var. ursinus and A. lentiginosus var. maricopae may
not be more than 5,000 each.
Astragalus lentiginosus var. maricopae, A. lentiginosus
var. wilsonii, A. lentiginosus var. ursinus do not exhibit the high levels of
chloroplast differentiation found in other taxa with peripheral disjunct populations.
The taxa with larger populations, A. lentiginosus var.mokiacensis, A. lentiginosus var. araneosus,
A. lentiginosus var. yuccanus, and A. lentiginosus var. palans have low
diversity, though more populations of these taxa will needed to be sampled to conclusively substantiate this pattern. An
alternative explanation is that A. lentiginosus var. maricopae, A. lentiginosus
var. wilsonii, and A. lentiginosus var. ursinus are relictual populations of a
taxon that gave rise to the more widespread A. lentiginosus var. mokiacensis and A. lentiginosus
var. palans. Unfortunately, the molecular and morphologic data do not give
many clues to which taxon more closely resembles the ancestor of the
Wayne H. Whaley, Ph.D.
The Indra Swallowtail Butterfly (Papilio indra: Lepidoptera) is found in
many small, scattered populations across the western United States and
lives in habitats and climates ranging from high moist mountain peaks and
rugged semiarid badlands to hot arid deserts. The many isolated
populations show substantial morphological variation, and 12 subspecies
are currently described in the literature. These subspecies vary in both
adult and larval appearance, and they frequently utilize different larval
host plants all of which are members of the Parsley family (Apiaceae).
Only 21 species of this very diverse family are utilized by the butterfly.
Several as yet unexplored desert mountain ranges likely support additional
distinctly different populations as evidenced by the recent discovery
(May 2000) of a genetically distinct population in northern Arizona.
Because of the species´ beauty and extreme geographic variation this is
probably the most popular and most collector-sought butterfly in North
America which, amongst other factors, warrants its conservation. In light
of future conservation initiatives and to better understand its population
dynamics and evolution we have recently implemented molecular genetic studies
of the Indra Swallowtail.
I have studied the biology and ecology of this butterfly and its larval host
plants for 12 years; students and I continue this work to delineate the
range of the species and subspecies in order to understand its ecological
requirements and evolutionary history. Over the past years I have discovered
several new populations, some of which are distinctly different. The ranges
of some of the subspecies have been extended. Some of the subspecies have
been found to overlap in zones of secondary contact where transitional forms
are present and will soon be described.
Due to the extreme geographical variation, this butterfly is ideal for studying
the speciation process. With this goal in mind, a colleague (Dr. J. V. Price)
and I recently began using mtDNA sequencing of COX I and II loci and PAUP
phylogenetic software for genomic analysis to determine the historical
phylogeography of the species and subspecies. Utilizing modern molecular
techniques of biosystematics (PCR, electrophoresis, gene sequencing) we are
investigating the degree of genetic divergence between the populations and
subspecies, the amount of gene flow between them, and we are working on their
phylogenies. Preliminary phylogenies have been computer generated using PAUP
software but not all the populations and subspecies have been sequenced and
included in the analysis. However some interesting discoveries have been made.
Our genetic analysis has shown that some undescribed and unnamed populations
show more genetic divergence from concensus Indra than the currently recognized
Several of the subspecies are restricted to only one or two of the larval host
plant species and, therefore, likely coevolved with them. Because the
biogeography of the plants and the butterfly are becoming well known, we have
expand the Indra research to include a phylogenetic analysis of the larval host
plants. It is expected that with the added plant data, insights will be gained
into the evolutionary patterns of divergence of the butterfly subspecies. In
the future host plant preference studies will be conducted across the 12