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411.
Saikat Naskar 《Nordic Journal of Botany》2020,38(8)
The nomenclatures of the taxa of the mangrove Rhizophoraceae of India have been scrutinized and 20 names are lectotypified or neotypified. In addition, the holotypes of some names are located for the first time with clarifications provided. Since natural hybridization is common in Rhizophoraceae, its consequences for the correct application of names is also briefly discussed. 相似文献
412.
413.
Recent research shows that using different types of enrichment has little to no impact on how zoo visitors perceive the animals or the enclosure in general. The primary objective of the current research was to examine if viewing naturalistic-looking environmental enrichment (NEE) and unnaturalistic-looking environmental enrichment (UEE) has an effect on visitor perceptions of exhibit naturalness, animal welfare, and conservation, while controlling for two factors that can influence visitor perspective: animal visibility and behavior. Study 1 examined the color of enrichment: the NEE was colored to resemble a rock and the UEE was fluorescent pink. Four conditions were recorded: Naturalistic/No Animal, Naturalistic/Animal, Unnaturalistic/No Animal, and Unnaturalistic/Animal. One video was shown to 306 randomly selected visitors who then took a survey including questions on animal welfare, exhibit naturalness, and supporting conservation organizations. Naturalistic/No Animal was perceived by visitors to be the most natural environment and the best of the exhibits for an animal to live in. Study 2 examined different types of NEE and UEE. Eight photos (four with an animal and four without) showing one out of four enrichment items (naturalistic rock, wood wool bedding, traffic cone, cardboard box) were shown to 618 randomly selected visitors who then took a survey similar to study 1. Visitors rated the photos with the NEE consistently higher for questions regarding the naturalness of the exhibit, good animal welfare, and the livability of the environment. Visitors were also asked to rank the four enrichment items from best to worst, and the NEEs were ranked significantly higher than the UEEs. While there are still many unanswered questions regarding visitor perceptions of environmental enrichment in zoos, we hope that focusing on one variant such as color and examining different types of NEE and UEE can help guide future studies on this subject. 相似文献
414.
Simon Luvo Magoswana James Stephen Boatwright Anthony R. Magee John C. Manning 《Nordic Journal of Botany》2020,38(3)
Othonna cerarioides Magoswana and J.C. Manning is described as a new species from Namaqualand, Northern Cape Province of South Africa. It is an erect shrub with rod-like stems and branches, bearing numerous spur-shoots with obovate-oblanceolate leaves clustered at the tips, and up to nine disciform capitula per spur-shoot. Othonna cerarioides is anomalous in the genus in that the style of some of the disc florets is bifid. Othonna is diagnosed within subtribe Othonnineae by female-sterile disc florets with simple (or very rarely minutely bifid) styles. The disc florets in the closely related genus Hertia are bisexual with well branched styles. 相似文献
415.
Kelly A. Hyndman Michael M. Miyamoto David H. Evans 《Molecular phylogenetics and evolution》2009,52(3):677-687
A gene phylogeny provides the natural historical order to classify genes and to understand their functional, structural, and genomic diversity. The gene family of endothelin receptors (EDNR) is responsible for many key physiological and developmental processes of tetrapods and teleosts. This study provides a well-defined gene phylogeny for the EDNR family, which is used to classify its members and to assess their evolution. The EDNR phylogeny supports the recognition of the EDNRA, EDNRB, and EDNRC subfamilies, as well as more lineage-specific duplicates of teleosts and the African clawed frog. The duplications for these nominal genes are related to the various whole-genome amplifications of vertebrates, jawed vertebrates, fishes, and frog. The EDNR phylogeny also identifies several gene losses, including that of EDNRC from placental and marsupial (therian) mammals. When coupled with structural and biochemical information, site-specific analyses of evolutionary rate shifts reveal two distinct patterns of potential functional changes at the sequence level between therian versus non-therian EDNRA and EDNRB (i.e., between groups without and with EDNRC). An analysis of linkage maps and tetrapod synteny further suggests that the loss of therian EDNRC may be related to a chromosomal deletion in its common ancestor. 相似文献
416.
Walter J. Bock 《Biology & philosophy》1994,9(3):267-327
Ernst Mayr's scientific career continues strongly 70 years after he published his first scientific paper in 1923. He is primarily a naturalist and ornithologist which has influenced his basic approach in science and later in philosophy and history of science. Mayr studied at the Natural History Museum in Berlin with Professor E. Stresemann, a leader in the most progressive school of avian systematics of the time. The contracts gained through Stresemann were central to Mayr's participation in a three year expedition to New Guinea and The Solomons, and the offer of a position in the Department of Ornithology, American Museum of Natural History, beginning in 1931. At the AMNH, Mayr was able to blend the best of the academic traditions of Europe with those of North America in developing a unified research program in biodiversity embracing systematics, biogeography and nomenclature. His tasks at the AMNH were to curate and study the huge collections amassed by the Whitney South Sea Expedition plus the just purchased Rothschild collection of birds. These studies provided Mayr with the empirical foundation essential for his 1942Systematics and the Origin of Species and his subsequent theoretical work in evolutionary biology as well as all his later work in the philosophy and history of science. Without a detailed understanding of Mayr's empirical systematic and biogeographic work, one cannot possibly comprehend fully his immense contributions to evolutionary biology and his later analyses in the philosophy and history of science. 相似文献