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Full-Text Articles in Life Sciences
Phylogenetic Relationships Among Fishes In The Order Zeiformes Based On Molecular Data From Three Mitochondrial Loci, Lindsay Scarpitta
Phylogenetic Relationships Among Fishes In The Order Zeiformes Based On Molecular Data From Three Mitochondrial Loci, Lindsay Scarpitta
Master's Theses
The Zeiformes (dories) are mid-water or deep (to 1000 m) marine acanthomorph fishes with a global, circumtropical, and circumtemperate distribution. Some species have a near-worldwide distribution, while others appear to be regional endemics, e.g., near New Zealand. Six families, 16 genera, and 33 species are currently recognized as valid. Relationships among them, however, remain unsettled, especially in light of recent proposals concerning the phylogenetic placement of zeiforms within the Paracanthopterygii rather than allied with beryciforms or percomorphs. The present study uses mtDNA characters to investigate zeiform interrelationships given their revised phylogenetic placement and attendant changes to their close outgroups, carried …
Evolution Of Life-History Characteristics In Gadoidei, Joshua Hittie
Evolution Of Life-History Characteristics In Gadoidei, Joshua Hittie
Master's Theses
Life-history characteristics (e.g., age and growth) have been used extensively to understand the temporal population dynamics of fish species, but less so within a phylogenetic framework. This study investigates life-history characteristics within the suborder Gadoidei (order: Gadiformes) and to test the extent of phylogenetic signal for those characteristics. To accomplish this, a phylogeny of Gadoidei was first constructed based on both mitochondrial and nuclear genes. Within this phylogenetic framework, life-history traits, including growth rate, age at maturity, and longevity, as well as ecological data, such as water depth and diet type, were mapped to the phylogeny using parsimony analysis to …
Experimental Evolution Of Specialism In A Wild Virus, Alexander Kula
Experimental Evolution Of Specialism In A Wild Virus, Alexander Kula
Master's Theses
A pathogen's ability to successfully replicate and persist within a new host population is fraught with obstacles. While an expanded host-range allows for a greater chance at successful replication, such generalists are typically outcompeted by species which have specialized and adapted host-specific features. Although the most ubiquitous species on earth, very few bacteria-infecting viral species (bacteriophages) with truly broad host-ranges have been identified; this is partially due to the fact that only a small fraction of bacteria (and thus likely hosts) are amenable to laboratory conditions. Nevertheless, the processes of expanding as well as narrowing host-range are not well understood …
The Status Of Leptodactylus Validus As A Single Taxon And Its Relationship To Letptodactylus Pallidirostris, Kenneth Christopher Yanek
The Status Of Leptodactylus Validus As A Single Taxon And Its Relationship To Letptodactylus Pallidirostris, Kenneth Christopher Yanek
Master's Theses
Leptodactylus validus exhibits an unusual distribution inhabiting Trinidad, Tobago, and the Lesser Antilles, but not the mainland of South America. This distribution is inconsistent with other distribution patterns observed for these islands. Although slight variation in adult morphology has been observed among the island populations, call data suggest the presence of a single species. Calls of Leptodactylus pallidirostris from Venezuela suggested that this taxon might be conspecific with L. validus. Herein sequence data from the 12S and 16S mt rRNA genes were collected and analyzed in order to address: 1.) whether more than one species is represented within L. validus, …