Biodiversity Commons^™

Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith

School of Biological Sciences: Faculty Publications

The catastrophic loss of large-bodied mammals during the terminal Pleistocene likely led to cascading effects within communities. While the extinction of the top consumers probably expanded the resources available to survivors of all body sizes, little work has focused on the responses of the smallest mammals. Here, we use a detailed fossil record from the southwestern United States to examine the response of the hispid cotton rat Sigmodon hispidus to biodiversity loss and climatic change over the late Quaternary. In particular, we focus on changes in diet and body size. We characterize diet through carbon (δ¹³C) and nitrogen …

Reorganization Of Surviving Mammal Communities After The End-Pleistocene Megafaunal Extinction, Anikó B. Tóth, S. Kathleen Lyons, W. Andrew Barr, Anna K. Behrensmeyer, Jessica L. Blois, René Bobe, Matt Davis, Andrew Du, Jussi T. Eronen, J. Tyler Faith, Danielle Fraser, Nicholas J. Gotelli, Gary R. Graves, Advait M. Jukar, Joshua H. Miller, Silvia Pineda-Munoz, Laura C. Soul, Amelia Villaseñor, John Alroy

School of Biological Sciences: Faculty Publications

Large mammals are at high risk of extinction globally. To understand the consequences of their demise for community assembly, we tracked community structure through the end- Pleistocene megafaunal extinction in North America.We decomposed the effects of biotic and abiotic factors by analyzing co-occurrence within the mutual ranges of species pairs. Although shifting climate drove an increase in niche overlap, co-occurrence decreased, signaling shifts in biotic interactions. Furthermore, the effect of abiotic factors on cooccurrence remained constant over time while the effect of biotic factors decreased. Biotic factors apparently played a key role in continental-scale community assembly before the extinctions. Specifically, …

Biotic Interchange Has Structured Western Hemisphere Mammal Communities, Danielle Fraser, S. Kathleen Lyons

School of Biological Sciences: Faculty Publications

Aim.— Many hypotheses posit that species-rich tropical communities are dominated by speciesspecies interactions, apparent as competitive exclusion or character displacement, whereas species-poor temperate communities are dominated by species-environment interactions. Recent studies demonstrate a strong influence of macroevolutionary and biogeographic factors. We simultaneously test for the effects of species interactions, climate, and biotic interchange on Western Hemisphere mammal communities using a phylogenetic and functional diversity approach.

Location.— Western Hemisphere.

Time period.— Modern

Major taxa studied.— Mammalia

Methods.— Using Western Hemisphere mammal distributional and body mass data, we calculate body mass dispersion, phylogenetic diversity (Net Relatedness Index), and assemblage-averaged rates of co-occurrence …

The Maintenance Of Phenotypic Divergence Through Sexual Selection: An Experimental Study In Barn Swallows Hirundo Rustica, Rebecca Safran, Yoni Vortman, Brittany R. Jenkins, Joanna K. Hubbard, Matt Wilkins, Rachel J. Bradley, Arnon Lotem

School of Biological Sciences: Faculty Publications

Previous studies have shown that sexual signals can rapidly diverge among closely related species. However, we lack experimental studies to demonstrate that differences in trait-associated reproductive performance maintain sexual trait differences between closely related populations, in support for a role of sexual selection in speciation. Populations of Northern Hemisphere distributed barn swallows Hirundo rustica are closely related, yet differ in two plumage-based traits: ventral color and length of the outermost tail feathers (streamers). Here we provide experimental evidence that manipulations of these traits result in different reproductive consequences in two subspecies of barn swallow: (H. r. erythrogaster in North …

Comparative Population Genomics Of Latitudinal Variation In Drosophila Simulans And Drosophila Melanogaster, Heather E. Machado, Alan O. Bergland, Katherine R. O'Brien, Emily L. Behrman, Paul S. Schmidt, Dmitri A. Petrov

School of Biological Sciences: Faculty Publications

Examples of clinal variation in phenotypes and genotypes across latitudinal transects have served as important models for understanding how spatially varying selection and demographic forces shape variation within species. Here, we examine the selective and demographic contributions to latitudinal variation through the largest comparative genomic study to date of Drosophila simulans and Drosophila melanogaster, with genomic sequence data from 382 individual fruit flies, collected across a spatial transect of 19 degrees latitude and at multiple time points over 2 years. Consistent with phenotypic studies, we find less clinal variation in D. simulans than D. melanogaster, particularly for the autosomes. Moreover, …

The Influence Of Balanced And Imbalanced Resource Supply On Biodiversity–Functioning Relationship Across Ecosystems, Aleksandra M. Lewandowska, Antje Biermann, Elizabeth T. Borer, Miguel A. Cebrián-Piqueras, Steven A.J. Declerck, Luc De Meester, Ellen Van Donk, Lars Ganfeldt, Daniel S. Gruner, Nicole Hagenah, W. Stanley Harpole, Kevin P. Kirkman, Christopher A. Klausmeier, Michael Kleyer, Johannes M. H. Knops, Pieter Lemmens, Eric M. Lind, Elena Litchman, Jasmin Mantilla-Contreras, Koen Martens, Sandra Meier, Vanessa Minden, Joslin L. Moore, Harry Olde Venterink, Eric W. Seabloom, Ulrich Sommer, Maren Striebel, Anastasia Trenkamp, Juliane Trinogga, Jotaro Urabe, Wim Vyverman, Dedmer B. Van De Waal, Claire E. Widdicombe, Helmut Hillebrand

School of Biological Sciences: Faculty Publications

Numerous studies show that increasing species richness leads to higher ecosystem productivity. This effect is often attributed to more efficient portioning of multiple resources in communities with higher numbers of competing species, indicating the role of resource supply and stoichiometry for biodiversity–ecosystem functioning relationships. Here, we merged theory on ecological stoichiometry with a framework of biodiversity–ecosystem functioning to understand how resource use transfers into primary production. We applied a structural equation model to define patterns of diversity– productivity relationships with respect to available resources. Meta-analysis was used to summarize the findings across ecosystem types ranging from aquatic ecosystems to grasslands …

Bacterial Community Structure Of Contrasting Soils Underlying Bornean Rain Forests: Inferences From Microarray And Next-Generation Sequencing Methods, Sabrina E. Russo, Ryan Legge, Karrie A. Weber, Eoin L. Brodie, Katherine C. Goldfarb, Andrew K. Benson, Sylvester Tan

School of Biological Sciences: Faculty Publications

Soil microbial diversity is vast, and we lack even basic understanding of how this diversity is distributed ecologically. Using pyrosequencing and microarray methods, we quantified the structure of bacterial communities in two contrasting soils underlying Bornean rain forest (clay and sandy loam) that differ markedly in soil properties, aboveground tree flora, and leaf litter decomposition rates. We found significant soil-related taxonomic and phylogenetic differences between communities that, due to their proximity, are independent of climate. Bacterial communities showed distinct compositional and taxon-abundance distributions that were significantly correlated with the structure of the overlying tree community. Richness of bacteria was greater …

Population Dynamics Of The Western Prickly Pear, Opuntia Macrorhiza (Cactaceae), Kathleen H. Keeler, Brigitte Tenhumberg

School of Biological Sciences: Faculty Publications

Although most cacti that have been studied are long lived, following individually marked plants in Boulder County, Colorado, for >7 years, we determined that average life span of Opuntia macrorhiza, the western prickly pear, is 3 years. A few individuals probably live >10 years. Vegetative reproduction, produced by rooting of cladodes, exceeded reproduction by germination and establishment from seeds. Both types of new recruits, from vegetative reproduction and seeds, had higher death rates than established plants. Size and frequency of flowering increased with age, although size both increased and decreased, sometimes dramatically, between years. Flowering correlated more strongly with …

Host Range Extension For Chlorochlamys Chloroleucaria (Geometrinae, Geometridae) To Include Eriogonum Alatum (Polygonaceae), Kathleen H. Keeler, George J. Balogh

School of Biological Sciences: Faculty Publications

In 2001 and 2002 we collected specimens of Chlorochlamys chloroleucaria from Eriogonum alatum Torr., winged false buckwheat. Eriogonum alatum occurs at elevations of 5000-10,000 feet on both sides of the Rocky Mountains, from Utah (Welsh et al. 1987) to western Nebraska, southeastern Wyoming (Dorn 1977) to western Oklahoma and the Texas panhandle to Arizona (Great Plains Flora Association 1986).

Clone Size Of Andropogon Gerardii Vitman (Big Bluestem) At Konza Prairie, Kansas, Kathleen H. Keeler, Charles F. Williams, Linda S. Vescio

School of Biological Sciences: Faculty Publications

Clone size of plants of Andropogon gerardii from Konza Prairie Biological Station, Manhattan, Kansas was estimated from spatial patterns of genetic variation, using proteins detected by starch gel electrophoresis and DNA content (ploidy) measured by flow cytometry. Unique multi-locus protein banding patterns and differences in ploidy were used to exclude plants as members of the same clone. Individual clones averaged about 2 m in diameter and areas of prairie of 100 m² were calculated to contain an average of 31.8 genetic individuals.

A Synopsis Of The Ferns And Fern Allies Of Nebraska, With Maps Of Their Distribution, Steven B. Rolfsmeier, Robert B. Kaul, David M. Sutherland

School of Biological Sciences: Faculty Publications

An annotated list and county-by-county distribution maps are presented for the 32 species of ferns and fern allies native to Nebraska, based upon field and herbarium studies and critical evaluation of the literature. Native to the state are Isoetes melanopoda, Selaginella rupestris, five species of Equisetum, and 25 species in 18 genera of ferns. Three native species are here verified for the first time, based upon recent collections: Matteuccia struthiopteris var. pensylvanica, Ophioglossum engelmannii, and Pellaeaglabella ssp. glabella. Isoetes melanopoda was rediscovered in 2000, the first record since 1941. Rejected are published reports …

Clonal Growth Of Lithospermum Caroliniense (Boraginaceae) In Contrasting Sand Dune Habitats, Stephen G. Weller, Kathleen H. Keeler, Barbara A. Thomson

School of Biological Sciences: Faculty Publications

The occurrence of clonal growth of distylous Lithospermum caroliniense was investigated in a population in the Nebraska Sandhills, an area where sand dunes have been relatively stable for at least 1,500–3,000 yr, and compared to a population occurring at the Indiana Dunes, an area of active sand dune formation. Spatial autocorrelation analysis indicated the occurrence of significant clonal propagation of genetically based floral morphs at Arapaho Prairie, but not for the Indiana Dunes. Apparent clonal growth in the Sandhills population had no overall negative effect on pollen deposition or fecundity relative to the Indiana population, although in some large clones …

Introduction From The Changing Prairie: North American Grasslands, Anthony Joern, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Preserving remaining North American grasslands requires a multiability approach. In this book, we investigate three aspects of an admittedly larger problem: (1) how we as humans perceive grasslands; (2) the ecology of grasslands, in order to define the framework within which conservation and preservation efforts must operate; and (3) conservation issues. Additional sociological, economic, philosophical, and cultural considerations will provide important additional insights to preserving and managing grasslands, but are not included here. By restricting our focus to only three issues, we feel that we can provide a basic, but appropriate, understanding of grassland ecosystems for the prairie enthusiast. This …

Getting The Lay Of The Land: Introducing North American Native Grasslands, Anthony Joern, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

The expected catastrophic extinction of species (already under way in many places) will alter the planet’s biological diversity so profoundly that, at the known rate of extinction, it will take millions of years to recover. Yet few ecologists study extinction. Indeed, very little ecology deals with any processes that last more than a few years, involve more than a handful of species, and cover an area of more than a few hectares. The temporal, spatial and organizational scales of most ecological studies are such that one can read entire issues of major journals and see no hint of impending catastrophe. …

Preface From The Changing Prairie: North American Grasslands, Kathleen H. Keeler, Anthony Joern

School of Biological Sciences: Faculty Publications

North American grasslands have figured prominently in our North American heritage. Prairies first provided significant barriers to westward expansion, and then offered both economic and sociological opportunity, as well as heartache, for settlers. Many artists have gained significant inspiration from the beauty as well as the harshness of this region and its biota. And because of ideal climate and soil conditions, these grasslands have provided the agricultural foundation of which much of the economic growth and stability of the United States has historically depended.

Yet many see North American prairies as beautiful only when manipulated or exploited: Green croplands or …

Population Processes, Kathleen H. Keeler, Anthony Joern

School of Biological Sciences: Faculty Publications

Within the prairies, myriad populations of plants, insects, small mammals, and other organisms form distinct levels of organization. The physical forces of weather and fire and the complex networks of species interactions control each species’s structure and dynamics and determine its abundance or rarity. Variation in population dynamics and interactions over time and space determine the distribution and abundance of species, and ultimately the composition and dynamics of entire prairie communities.

To the casual observer, plant populations on prairies may seem quite static, like museums containing a diverse collection of specimens that can be seen again and again on repeated …

Wild Medicine: Review Of Medicinal Wild Plants Of The Prairie By Kelly Kindscher, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

I am highly enthusiastic about this book as a reference work. It summarizes the literature on the medicinal uses for more than 103 prairie plants. For 43 species, Kindscher gives common, Indian, and scientific names; description; habitat; parts used; Indian uses; medical history; scientific research and cultivation; and information on about 100 of their relatives. Another 60 entries are condensed to 24 paragraphs. Full-page line drawings by William S. Whitney of the major species are generally excellent, and all 103 entries have distribution maps. The introduction discusses the region covered, with helpful maps. There's an index, a glossary and a …

Fifteen Years Of Colony Dynamics In Pogonomyrmex Occidentalis, The Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Ecological communities respond to environ- mental changes as the individuals of the component species die and are replaced. Thus, pat- terns of population turnover form an important aspect of community processes. Much less is known about species of long-lived individuals than of short-lived ones (Likens, 1989).

Instantaneous observations of age structure can be used to infer long-term dynamics but not all species can be aged retrospectively. Inferring life- history dynamics from current populations requires assumptions that are hard to verify. Following marked colonies of long-lived species is slow but provides direct, non-inferential data on population dynamics, although those are specific …

Local Polyploid Variation In The Native Prairie Grass Andropogon Gerardii, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

The microscale distribution of polyploid variants of the dominant grass big bluestem (Andropogon gerardii) in virgin tallgrass prairie was mapped using flow cytometry. The correlation between DNA content and polyploidy allows the use of flow cytometry for nondestructive determination of polyploidy in intact plants. At Konza Prairie, local plots contained from 0 to 100% hexaploid cytotypes but most showed fine-scale mixing of the polyploid variants. The relationship of cytotype frequency to moisture availability or burning history was nonsignificant

Colony Survivorship In Pogonomyrmex Occidentalis, Western Harvester Ant, In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Little is known about the life span of individual ant colonies (Keeler, 1981), even though the dynamics of some species, such as harvester ants, are crucial to the structure of plant and animal communities (e.g., Brown et al., 1979). This note reports the results of 10 years of observations on a population of harvester ants.

Fifty-six mounds of Pogonomyrmex occidentalis Cresson (Hymenoptera: Formicidae), western harvester ant, were permanently marked with aluminum tags in August 1977. The site, about 1 ha just south of the University of Nebraska's Cedar Point Biological Station, Keith Co., Nebraska, was within a pasture subject to …

Vegetation Patterns In Relation To Topography And Edaphic Variation Nebraska Sandhills Prairie, P. W. Barnes, A. T. Harrison, S. P. Heinisch

School of Biological Sciences: Faculty Publications

Detailed studies on soil texture and moisture retention indicate a close association between edaphic features and the distribution and composition of plant communities along topographic gradients at Arapaho Prairie, a typical, semi-arid Nebraska Sandhills prairie. The vegetation characteristics of three major habitat types (ridge, slope, and valley) and several minor subtypes (swale, stable ridge, and eroding ridge) are recognized and quantitatively described. Texture analysis indicates that the soils of dune slopes and ridges are largely azonal and are very coarse with substantially lower fine fractions (silt-clay ~ 13-15%) than soils of the more lowland swale and valley sites where surfact …

Comparison Of Old Field Succession On A Tallgrass Prairie And A Nebraska Sandhills Prairie, Mary Bomberger Brown, Shelly L. Shields, A. Tyrone Harrsion, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Long held to be reasonably well understood, the process of ecological succession has recently come under attack. The predictability of successional changes has been doubted (Walker 1970), the mechanism of species replacement has been questioned (Connell and Slatyer 1977), and the reality of steady-state (climax) challenged (Botkin and Sobel 1975, Connell and Slatyer 1977, Connell 1978). In particular, several communities are presently recognized as having "cyclic succession" (Ricklefs 1973), in which the process is continually repeating. Such communities include heaths (Watt 1947), prairie pot-hole marshes (Vander Valk and Davis 1978), spruce-fir forests (Sprugel 1976, Sprugel and Bormann 1981), and intertidal …

Preliminary Report Of Colony Survivorship In The Western Harvetser Ant (Pogonomyrmex Occidentalis) In Western Nebraska, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Colonies of Pogonomyrmex occidentalis Cresson (Hymenoptera: Formicidae) may live an average of 22 to 43 years. The population dynamics of individual colonies of P. occidentalis adjacent to the Univ. Nebraska's Cedar Point Biol. Sta., Keith Co., Nebraska, is the subject of an ongoing investigation. The habitat is a moderately grazed shortgrass prairie dominated by Bouteloua hirsuta, B. gracilis, and Buchloe dactyloides, with Stipa comata, Aristida spp., and various forbs. The colonies studied are in a triangular area about 400 m long and 100 m across at the widest point. The area appears to be at carrying …

Legume Distribution And Nodulation In Arapaho Prairie, Arthur County, Nebraska, L. A. Kapustka, J. D. Dubois

School of Biological Sciences: Faculty Publications

Vegetational sampling of the legumes of Arapaho Prairie, located in the southwest portion of the Sand Hills of Nebraska, was conducted in June 1980. Lathyrus polymorphus, Petalostemon purpureum, Psoralea digitata and Amorpha canescens were the leading dominants. The overall density of legumes was 0.309 plants m^-2.

Of eight examined, only Petalostemon villosum and Glycyrrhiza lepidota supported large numbers of nodules. The others including the dominant legumes were unnodulated or had only a few, usually degenerate nodules.

It appears that the legumes are of minor importance in the overall N economy of Arapaho Prairie. Nevertheless since many …

Cover Of Plants With Extrafloral Nectaries At Four Northern California Sites, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Percent cover of plants with extrafloral nectaries was investigated in three California habitats with the same physiognomy as habitats previously studied in Nebraska (perennial native grassland, riparian forest, deciduous forest). In contrast to Nebraska where cover of plants with extrafloral nectaries reached 14 percent, no plants with extrafloral nectaries were found in any California transect. Chaparral was also studied; no plants with extrafloral nectaries were found.

The Flora And Sandhills Prairie Communities Of Arapaho Prairie, Arthur County, Nebraska, Kathleen H. Keeler, A. T. Harrison, L.S. Vescio

School of Biological Sciences: Faculty Publications

The Arapaho Prairie is a 526-hectare (two-section) tract of upland Sandhills prairie located approximately nine miles southwest of the town of Arthur in Arthur Co., Nebraska (Sec. 31, 32 T18N R39W). The Prairie is at the extreme southwest edge of the 52,000-km² Nebraska Sandhills (see Kaul 1975) and is floristically and ecologically typical of the slightly drier, western part of this vegetation type. Sandhills prairie which stretches across much of north central Nebraska is a unique type of "mixed" grassland (Pool 1914, Rydberg 1931, Tolstead 1942, Weaver 1965) created by impact of the dry, continental climate on the extensive …

Morphology And Distribution Of Petiolar Nectaries In Ipomoea (Convolvulaceae), Kathleen H. Keeler, Robert B. Kaul

School of Biological Sciences: Faculty Publications

The distribution of petiolar nectaries in 24 species of Ipomoea was investigated. Petiolar nectaries were found on 12 species (8 new reports, 4 confirmations of previous reports) and quoted from the literature as being found on 3 other species; they were absent from 9 species investigated. The structure of petiolar nectaries in the genus ranges from simple beds of superficial nectar-secreting trichomes (1 species), to slightly recessed "basin nectaries" (8 species), to "crypt nectaries," which are structurally the most complex extrafloral nectaries known (3 species). (Structures were not determined for 3 species.) Petiolar nectaries are present in all subgenera, but …

Distribution Of Plants With Extrafloral Nectaries And Ants At Two Elevations In Jamaica, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Frequencies of plants with extrafloral nectaries were determined for two elevations in Jamaica. Extrafloral nectaries were found on 0.28 of the plants at sea level (Happy Grove, Portland) and 0.00 of the plants at 1310 m (Whitfield Hall, St. Thomas). Ant abundance, as indicated by discovery of and recruitment to baits, was greater at the lower elevation site. However, despite the apparent absence of plants with extrafloral nectaries, there were abundant ants at 1310 m.

Species With Extrafloral Nectaries In A Temperate Flora (Nebraska), Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Extrafloral nectaries (EFNs) are glands on a plant, not involved in pollination, that produce solutions containing sugars (and other compounds). Long noted by morphologists, EFNs have recently been observed to be part of ant-plant mutualisms. The function of EFNs appears to be to attract aggressive insects, especially ants, which by disturbing or preying upon herbivores, reduce damage to the plant (Janzen, 1966a,b; Elias and Gelband, 1975; Keeler, 1975, 1977; Bentley, 1976, 1977a,b; Schemske, 1978; Tilman, 1978; Inouye and Taylor, 1979; Pickett ad Clark, 1979). Furthermore, they constitute an unusual plant defense against herbivores: at EFNs plants employ ants as a …

A Bibliography Of Taxonomic Literature Of The Great Plains Flora, With Supplements I, Ii, And Iii, Ralph E. Brooks

School of Biological Sciences: Faculty Publications

There is at present no recent comprehensive manual of the Great Plains flora. Consequently, students of the flora must utilize monographs, revisions, and other sources in their work. This bibliography was compiled in order to facilitate location of available literature, and will be useful to anyone interested in the systematics of the plants of the Great Plains. This compilation was produced for the Great Plains Flora Association as an initial step in the preparation of a major flora for the region.

References to the plants of the Great Plains region as recognized in the Atlas of the Great Plains Flora …