Browsing by Author "Beukes, Brandon"

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    Does phylogeny have an influence on the date of first description? A comparative study of the world's fishes
    (Elsevier, 2020) Beukes, Brandon; Witbooi, Peter; Gibbons, Mark J.
    The process of species description is not random, and understanding the factors that in- fluence when a species is first described (the date of first description, DoFD) allows us to target environments and/or species' traits to increase our knowledge of diversity. Such studies typically correlate species traits (e.g. maximum size, occupational depth) against DoFD, forgetting that species are not statistically independent of each other, owing to the inheritance of shared characteristics. A recent study of extant fishes by Costello et al. (2015) identified depth and geographic range size as the most important (of many) pre- dictors of the DoFD, implying that newly described species will likely occupy restricted areas and occur deep in the water column. However, these authors failed to accommodate for “identity by descent” in their analyses. We correct that oversight here, and conclude that while the adjustments strengthen the associations between the different predictors and the DoFD, the overall affects are minimal and they do not materially change Costello et al.’s (2015) conclusions. This is briefly discussed.
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    Does phylogeny have an influence on the date of first description? A comparative study of the world's fishes
    (Elsevier, 2020) Beukes, Brandon; Witbooi, Peter Joseph; Gibbons, Mark J.
    The process of species description is not random, and understanding the factors that influence when a species is first described (the date of first description, DoFD) allows us to target environments and/or species' traits to increase our knowledge of diversity. Such studies typically correlate species traits (e.g. maximum size, occupational depth) against DoFD, forgetting that species are not statistically independent of each other, owing to the inheritance of shared characteristics. A recent study of extant fishes by Costello et al. (2015) identified depth and geographic range size as the most important (of many) predictors of the DoFD, implying that newly described species will likely occupy restricted areas and occur deep in the water column. However, these authors failed to accommodate for “identity by descent” in their analyses.
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    Examining intra- and interspecific variability in the diet and carbon and nitrogen stable isotope ratios of kingklip and monkfish caught off the West and South coasts of South Africa
    (University of Western Cape, 2020) Beukes, Brandon; Gibbons, Mark John
    Kingklip (Genypterus capensis) and monkfish (Lophius vomerinus) and are ecologically and economically important demersal fish species that are found along both the eastern and western parts of southern Africa’s coastline. Despite their commercial value, limited information exists focusing on the trophic ecology of these two species. This is the first study to make use of both stomach content analysis and stable isotope analysis to directly compare and examine the trophic ecology of G. capensis and L. vomerinus off the West and South coast of South Africa.