• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 63
  • 15
  • 14
  • 4
  • 3
  • 2
  • 1
  • Tagged with
  • 124
  • 18
  • 13
  • 12
  • 12
  • 11
  • 11
  • 11
  • 10
  • 8
  • 8
  • 8
  • 7
  • 7
  • 7
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Investigating the use of herbicides to control invasive grasses in prairie habitats effects on non-target butterflies /

LaBar, Caitlin C. January 2009 (has links) (PDF)
Thesis (M.S. in environmental science)--Washington State University, May 2009. / Title from PDF title page (viewed on May 29, 2009). "Program in Environmental Science and Regional Planning." Includes bibliographical references (p. 23-29).
22

The evolution and ecological genetics of pupal color dimorphism in swallowtail butterflies (Lepidoptera: Papilioninae) /

Hazel, Wade Nelson, January 1980 (has links)
Thesis--Virginia Polytechnic Institute and State University. / Vita. Abstract. Includes bibliographical references (leaves 85-88). Also available via the Internet.
23

Genetický pohled na mizejícího motýla: situace druhu \kur{Argynnis} niobe / Population genetics and phylogeography of a vanishing species: the case of \kur{Argynnis niobe}

LEŠTINA, Dan January 2015 (has links)
This study evaluates the state of the Niobe fritillary (Argynnis niobe) in Europe, both in terms of (a) current knowledge of its distributional changes and of (b) the genetics of the surviving populations. It uses mitochondrial sequences and microsatellite markers to assess the phylogeographic history of the species, and the impact of the multiple local extinctions at the same time. The data are evaluated by a standard set of methods genetics and phylogeography population and a brief synthesis including recommendations for conservation management is given.
24

The ecology and evolution of wetland butterflies with emphasis on the genus Euphyes (Lepidoptera: Hesperiidae) /

Shuey, John Allen January 1986 (has links)
No description available.
25

Sustainable landscape design for Fung Yuen butterfly reserve garden

Chui, Chi-keung, Chris, January 2007 (has links)
Thesis (M. L. A.)--University of Hong Kong, 2007. / Title proper from title frame. Includes special report study entitled: Detail investigation on the sustainable landscape design principles. Also available in printed format.
26

Effects of pesticides on non-target invertebrates in arable crops and field boundaries

Cilgi, Tamer January 1994 (has links)
No description available.
27

Biodiversity patterns of butterflies and moths on Mount Cameroon

MAICHER, Vincent January 2019 (has links)
Biodiversity patterns of butterflies and moths are investigated on the southwestern slope of Mount Cameroon, the only continuous elevational gradient of near-pristine forests in the Afrotropics. Three distinct seasons between 2014 and 2017 are sampled by two standardised methodologies (i.e., bait-trapping and manual catching of selected groups of moths at light). First, the effects of seasonality and forest habitat associations on butterflies and moths are investigated in the lowland rainforest. Then, the impacts of elephant-made natural disturbances on tree, butterfly, and moth diversities at mid-elevations is evaluated. The thesis also includes faunistic records of species never reported from the area, combining them with life history notes on selected taxa and species description of nine new species of Alucita. Finally, the last chapter focuses on the biodiversity of birds, trees, and butterflies in the last large patch of coastal forest of the studied area, and discusses its current conservation status.
28

Investigating the Impact of Habitat Disturbance and the Role of Functional Traits in a Tropical Butterfly Assemblage

Suman, Attiwilli January 2017 (has links) (PDF)
Tropical habitats face a diverse range of anthropogenic threats. Two common and important threats to tropical biodiversity are invasive species and roads. Invasive plants are proposed to be a major threat to biodiversity worldwide, yet not much is known about their impacts on higher trophic levels, such as insects. Roads and other linear intrusions, such as power lines and railway tracks, are another common aspect of human disturbance in natural landscapes, including tropical forests, and are often linked to the spread of invasive plants. I studied impacts of these two important proximate drivers of habitat disturbance, namely invasive plant species and roads, on habitat use by butterflies in a tropical moist deciduous forest in Western Ghats of India. Invasive plants and roads are expected to modify micro-habitat structure, resources and other aspects of ecology of butterflies and thereby influence how they use space (i.e., micro-habitats within the larger habitat). Because systematic ecological information on tropical butterflies is comparatively limited, I adopted a multi-species approach. I examined space use responses of butterflies to a gradient of lantana cover in the forest and to a road passing through forest. The abundance of different species of butterflies in different micro-habitats was taken as a measure of habitat use. Data was collected over two seasons and at two spatial scales. The two habitat disturbances were found to influence local habitat use by butterflies. But interestingly, species appeared to respond differently, with some showing positive, others negative and some no clear association with road verge or lantana gradient. I then examined whether this variation in response could be understood in terms of species-specific functional traits. Correlating the responses of species to a habitat disturbance with functional traits may provide a way of arriving at general patterns and increase the ability of studies to predict responses. Species with similar trait values are expected to respond similarly to a habitat change driver. I measured morphological traits in 254 butterfly species from India and classified them according to their habitat preferences (based on expert opinion). I first examined relationships between morphological traits, habitat preferences and evolutionary relatedness. I then examined patterns of correlation between these traits and responses to the two habitat disturbances and found that certain traits can help predict responses. Overall, my study suggests that butterfly space use is influenced by roads and lantana, but the response varies across species. These changes in habitat use might have important population or community-level consequences, such as population declines and shifts in community structure and composition; these need to be further examined.
29

Quantifying the Predictability of Evolution at the Genomic Level in Lycaeides Butterflies

Chaturvedi, Samridhi 01 August 2019 (has links)
Stephen Jay Gould, a great scientist and evolutionary biologists, suggested that if we could replay the tape of life, we would not have observed similar course of events because evolution is stochastic and if affected by several events. Since then, the possibility that evolution is repeatable or predictable has been debated. Studies using large-scale evolution experiments, long-term data for individual populations, and controlled experiments in nature, have demonstrated phenotypic and genetic convergence in several taxa. These studies suggest that despite some randomness, predictable evolutionary patterns can emerge on a large temporal and spatial scale. However, a few cases also exist where evolution is unpredictable and stochastic. One way to understand evolutionary predictability better can be to have quantitative estimates of predictability at different heirarchical levels (mutations, genetic, phenotypic). This can help better understand if evolution is predictable and the extent to which it is predictable. My dissertation uses Lycaeides butterflies to identify and quantify evolutionary predictability in different contexts such as on a geographic scale, temporal scale and genomic scale. I accomplished this by sequencing and annotating the genomes of these butterflies across a vast geographic range and on a temporal scale and by comparing natural and experimental populations. My results show that different mechanisms can assist evolution of organisms to adapt to novel environmental challenges, and that the evolutionary changes can be somewhat predictable. Through this work I demonstrate three main findings: first, quantitative estimates of evolutionary predictability indicate that degree of predictability is variable and is highly context-dependent. Second, we can predict evolutionary patterns on a spatial as well as temporal scale, and can predict patterns in nature by controlled laboratory experiments. Additionally, genomic changes underlying repeatability vary across the genome. Lastly, the approach of quantifying predictability can help us better understand the mechanisms which drive evolution and how organisms will evolve in response to similar environmental pressures. These results suggest that evolution can be constrained and if we actually replay the tape of life, we could see a considerably similar outcome in biodiversity compared to what Gould predicted.
30

The Pararge species of Madeira : an examination of the role of interspecific competition

Harrison, Emma Clare January 2001 (has links)
No description available.

Page generated in 0.0958 seconds