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Full-Text Articles in Life Sciences
Evolution Of Lake Malawi Cichlid Fishes (Perciformes: Teleostei), Peter F. Smith
Evolution Of Lake Malawi Cichlid Fishes (Perciformes: Teleostei), Peter F. Smith
Electronic Theses and Dissertations
The cichlid fish species flocks of East Africa provide a compelling model system in which to study the process of speciation. In Lake Malawi, greater than 1000 species of cichlids have emerged since the filling of the lake basin about 1 million years ago. Over 99% of the Lake Malawi haplochromine cichlids are endemic, suggesting that most of this diversification has taken place within the temporal and spatial boundaries set by the Lake's shores. Moreover, many of these species are endemic to small areas within the lake, indicating that speciation has occurred very recently or perhaps is in progress in …
Systematics Of The Cumacea (Crustacea), Pilar A. Haye
Systematics Of The Cumacea (Crustacea), Pilar A. Haye
Electronic Theses and Dissertations
Cumaceans are small benthic crustaceans. They have a marine cosmopolitan distribution with diversity increasing with depth. There are approximately 1,400 described species of cumaceans. Despite the fact that they offer a good model for the study of morphological evolution and biogeography, the studies on the Order Cumacea are almost restricted to work at the alpha taxonomy level. This thesis contributes to the systematics of Cumacea. The phylogenetic relationships within the Cumacea were studied using newly obtained partial amino acid sequences from the mitochondria1 gene Cytochrome Oxidase I. Among other findings, phylogenetic analyses revealed that the families Bodotriidae, Leuconidae, and Nannastacidae, …
The Value Of Rockweed (Ascophylum Nodosum) As Habitat For Tidepool Fishes, Amy Marie Gullo
The Value Of Rockweed (Ascophylum Nodosum) As Habitat For Tidepool Fishes, Amy Marie Gullo
Electronic Theses and Dissertations
Tidepool fishes are an interesting and commercially valuable guild of fishes that reside in tidepools at low tide. Tidepool fishes of the North Atlantic Coast reside in tidepools only during the late spring to Ml months, and are typically juveniles of subtidal adult species. Tidepool fishes on the Pacific Coast of North America have been studied extensively, but species of the North Atlantic Coast have rarely been studied. An important area of study is the use of different tidepool microhabitats by fishes, specifically the use of rockweed (AscophyZZum nodosum) fringe, which is present in many tidepools. Rockweed is an algal …
The Relationship Between Green Sea Urchin Spawning, Spring Phytoplankton Blooms, And The Winter-Spring Hydrography At Selected Sites In Maine, Lindsay C. N. Seward
The Relationship Between Green Sea Urchin Spawning, Spring Phytoplankton Blooms, And The Winter-Spring Hydrography At Selected Sites In Maine, Lindsay C. N. Seward
Electronic Theses and Dissertations
The relationship between green sea urchin spawning, spring phytoplankton blooms, and hydrography were examined at multiple spatial scales during the winter-spring of 2000 at selected sites along the coast of Maine. To determine factors contributing to the variation observed in the timing of green sea urchin spawning, sea urchins, phytoplankton, and oceanographic variables were sampled biweekly at four sites in central Maine and three sites in eastern Maine. Water column properties and phytoplankton was intensively examined at sites in central Maine, while sites in eastern Maine were less well characterized. Analysis of gonad indices showed that spawning was protracted in …
The Embryonic World Of Wood Frogs, Rana Sylvatica: Natal Pond Learning And Anti-Predator Behaviors., Pamela J. Bryer
The Embryonic World Of Wood Frogs, Rana Sylvatica: Natal Pond Learning And Anti-Predator Behaviors., Pamela J. Bryer
Electronic Theses and Dissertations
Even while in ovo many amphibians can react to the world around them, as dissolved molecules are able to pass through their protective jelly matrix and interact with developing sensory systems. Although there are many potential signals dissolved in the water, two, natal-pond recognition cues and predator recognition signals (or kairomones), have been previously shown to be relevant to several species of developing anurans. My study used natural odorants in a test of natal pond learning, and in testing both short- and long-term effects of predator chemical cues on the development and behavior of wood frog, Rana sylvatica, embryos. In …