1,721,119 research outputs found
A new species of Lethrinops (Cichliformes: Cichlidae) from a Lake Malawi satellite lake, believed to be extinct in the wild
No full textTurner, George F., Crampton, Denise A., Genner, Martin J. (2023): A new species of Lethrinops (Cichliformes: Cichlidae) from a Lake Malawi satellite lake, believed to be extinct in the wild. Zootaxa 5318 (4): 515-530, DOI: 10.11646/zootaxa.5318.4.5, URL: http://dx.doi.org/10.11646/zootaxa.5318.4.
Coexistence of Lake Malawi cichlid fishes
No full textSIGLEAvailable from British Library Document Supply Centre-DSC:DXN031640 / BLDSC - British Library Document Supply CentreGBUnited Kingdo
Foraging of rocky habitat cichlid fishes in Lake Malawi: coexistence through niche partitioning?
No full textThe haplochromine cichlid fish communities of the rocky habitats of Lake Malawi are highly diverse; however, many species live side by side with apparently very similar resource requirements. There is a long-standing debate concerning whether these species partition their resources on a finer scale than has been previously reported or if species that are truly ecologically indistinguishable can coexist. A field study of food resource use was conducted to determine whether coexisting species segregate their diet and foraging sites. Significant differences between species were found, yet considerable inter-specific resource use overlap was commonplace. The data indicate that these cichlid species coexist both with and without niche differentiation. We propose that alternatives to niche differentiation should be considered to explain how many species coexist in Lake Malawi cichlid communities
Lethrinops lethrinus
No full text<i>Lethrinops lethrinus</i> (Günther, 1893) <p> <b>Holotype:</b> <i>Lethrinops lethrinus</i> (Günther, 1893): BMNH 1893.11.15.15, 116.1 mm SL, coll. A. Whyte, Upper Shire River at Fort Johnston (Mangochi), March 1892,</p>Published as part of <i>Turner, George F., Crampton, Denise A. & Genner, Martin J., 2023, A new species of Lethrinops (Cichliformes: Cichlidae) from a Lake Malawi satellite lake, believed to be extinct in the wild, pp. 515-530 in Zootaxa 5318 (4)</i> on page 526, DOI: 10.11646/zootaxa.5318.4.5, <a href="http://zenodo.org/record/8181908">http://zenodo.org/record/8181908</a>
Contrasting demographic histories of European and North American sea lamprey (Petromyzon marinus) populations inferred from mitochondrial DNA sequence variation
No full textPopulations of anadromous sea lamprey (Petromyzon marinus) have been found to be largely genetically homogeneous across western Europe, and across the eastern seaboard of North America. However, comparatively little is known of the relationship between the European and North American populations. We quantified the extent of population structuring present over a transatlantic scale using mitochondrial DNA sequences. We found clear segregation of the populations on either side of the Atlantic, and considerable genetic homogeneity within Europe over a spatial scale of over 2000 km. The North American populations contained larger genetic diversity than those from Europe, and coalescent analyses showed a corresponding greater overall effective population size. Employing calibration points based on a dated phylogeny of the Petromyzontiformes, our analyses indicated that the North American population has been increasing in effective size since establishment ~500 000 years ago, while the total European population has only undergone population expansion only within the last 125 000 years. This evidence is consistent with a colonisation of Europe from an older North American population, and with the European population persisting through the last glaciation within regional refugia
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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