Publications by authors named "D L Weese"
Article Synopsis
- Francisella orientalis is a harmful bacteria that causes high death rates in warmwater fish like tilapia and has significantly impacted aquaculture worldwide, resulting in a moratorium on tilapia exports from Oahu since the mid-1990s due to repeated outbreaks.
- A study was conducted to evaluate the presence of this bacteria in feral tilapia from various Hawaiian Islands using molecular and histological screening methods.
- The results showed infection signs in fish from all five islands, but F. orientalis was only confirmed in Oahu, Maui, and Kauai, indicating its widespread prevalence among feral tilapia populations.
Article Synopsis
- - The study investigates how tectonic activity from the collision of Indian-Asian plates and Tibetan Plateau uplift has affected the drainage systems of East Asian rivers, particularly the upper Changjiang (Yangtze) River, through a focus on freshwater fish evolution.
- - By analyzing mitochondrial DNA (mtDNA) of endemic fish from the eastern Tibetan Plateau, researchers identified a new genetic grouping (clade D) with several clusters linked to various river systems in the region, indicating complex historical drainage connections.
- - Key findings suggest specific ancient connections and captures among these rivers, like the upper Yalong being an origin for fish dispersal and the existence of a palaeo-lake that played a significant role in the evolutionary history of the fish in
Because genotypes within a species commonly differ in traits that influence other species, whole communities, or even ecosystem functions, evolutionary change within one key species may affect the community and ecosystem processes. Here we use experimental mesocosms to test how the evolution of reduced cooperation in rhizobium mutualists in response to 20 years of nitrogen fertilization compares to the effects of rhizobium presence on soil nitrogen availability and plant community composition and diversity. The evolution of reduced rhizobium cooperation caused reductions in soil nitrogen, biological nitrogen fixation, and leaf nitrogen concentrations that were as strong as, or even stronger than, experimental rhizobium inoculation (presence/absence) treatments.
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- * A study focused on the unique layered microbial crusts in Hawaii's anchialine ecosystem revealed that deeper layers had more diverse microbial communities, with more similarity within geographic sites than between different sites.
- * The research identified distinct oxygenated and anoxygenated niches in the crust layers, suggesting that environmental factors have driven the similar structures of these communities despite geographic differences.
Premise: Nutrients, light, water, and temperature are key factors limiting the growth of individual plants in nature. Mutualistic interactions between plants and microbes often mediate resource limitation for both partners. In the mutualism between legumes and rhizobia, plants provide rhizobia with carbon in exchange for fixed nitrogen.
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