Showing papers by "Trevor D. Price published in 2021"

200 Years of Research on Himalayan Biodiversity: Trends, Gaps, and Policy Implications

Abstract: Global mountains, including the Himalaya, are highly vulnerable ecosystems, especially given climate and land use change. We compiled the literature on Himalayan biodiversity in order to assess spatial and taxonomic trends of research during past 200 years. We identified 35,316 research outputs, including 28,120 journal articles, 3,725 doctoral theses and 3,471 books. Nepal contributes the largest volume of published literature, followed by west Himalayan Indian states, with relatively few studies on the most biodiverse region, lying to the east of Nepal. Publications on Himalayan biodiversity research have increased annually, especially after 1970, with an acceleration since 2000. Among the major taxonomic groups, the largest number of publications is on seed plants (Angiosperms), followed by invertebrates (especially arthropods) and vertebrates. Some groups of organisms notably fungi, bacteria, algae, bryophytes, pteridophytes etc. are clearly under-studied. Among various research disciplines, ecology is the most dominant field followed by agriculture, ethnobiology and paleontology. Some newer disciplines, including molecular biology and climate change, have contributed to the growth in the number of papers appearing during last two decades. Despite an encouraging and rapid increase in research papers during this century, they are largely in low impact factor journals, likely to subject to poor peer review and many doctoral theses remain unpublished. The Government of India’s development initiative emphasizes the importance of research in the Himalaya, which can be enhanced by improved quality of peer review and local journals registering in global indexing services.

Dispersal syndromes drive the formation of biogeographical regions, illustrated by the case of Wallace's Line.

Abstract: Aim Biogeographical regions (realms) reflect patterns of co-distributed species (biotas) across space. Their boundaries are set by dispersal barriers and difficulties of establishment in new locations. We extend new methods to assess these two contributions by quantifying the degree to which realms intergrade across geographical space and the contributions of individual species to the delineation of those realms. As our example, we focus on Wallace's Line, the most enigmatic partitioning of the world's faunas, where climate is thought to have little effect and the majority of dispersal barriers are short water gaps. Location Indo-Pacific. Time period Present day. Major taxa studied Birds and mammals. Methods Terrestrial bird and mammal assemblages were established in 1-degree map cells using range maps. Assemblage structure was modelled using latent Dirichlet allocation, a continuous clustering method that simultaneously establishes the likely partitioning of species into biotas and the contribution of biotas to each map cell. Phylogenetic trees were used to assess the contribution of deep historical processes. Spatial segregation between biotas was evaluated across time and space in comparison with numerous hard realm boundaries drawn by various workers. Results We demonstrate that the strong turnover between biotas coincides with the north-western extent of the region not connected to the mainland during the Pleistocene, although the Philippines contains mixed contributions. At deeper taxonomic levels, Sulawesi and the Philippines shift to primarily Asian affinities, resulting from transgressions of a few Asian-derived lineages across the line. The partitioning of biotas sometimes produces fragmented regions that reflect habitat. Differences in partitions between birds and mammals reflect differences in dispersal ability. Main conclusions Permanent water barriers have selected for a dispersive archipelago fauna, excluded by an incumbent continental fauna on the Sunda shelf. Deep history, such as plate movements, is relatively unimportant in setting boundaries. The analysis implies a temporally dynamic interaction between a species' intrinsic dispersal ability, physiographic barriers, and recent climate change in the genesis of Earth's biotas.

The Sensory Ecology of Birds

Abstract: From calling someone eagle-eyed to expecting owls to possess perfect night vision, many of us hold assumptions about the sensory abilities of birds. There are also many aspects of bird biology that lead us to wonder how they sense their world. How do penguins catch fish underwater? How is it possible for birds to sense the earth’s magnetic field? Bridging disciplines from neurobiology to evolutionary biology, sensory ecology is concerned with what information is available to an individual, how the individual receives the information, and how its sensory systems are shaped by its ecology and social behavior. Sensory ecology is a relatively modern field with deep roots. Much of the foundational work originated with visual ecologists working on the effects of aquatic light environments on the sensory systems of fish, but the field has rapidly expanded to encompass many taxa and senses. In this concise volume, Martin introduces the reader to the diverse sensory world of birds. The book is written for an academic audience, but it is appropriate for anyone eager to learn more about bird sensory perception. We reviewed this book for a weekly lab meeting, and each of us learned something new despite our diverse positions that spanned from new graduate student to ancient professor. Throughout the book, Martin emphasizes the fundamental premise that not only is human perception insufficient to make generalizations about the sensory world of birds, but also that there is no singular “birds-eye view” experience, as every bird species is different. In support of this view, Martin describes extraordinary adaptations as he reviews 6 sensory modalities known in birds: vision, hearing, olfaction, touch, taste, and magnetoreception. Our collective knowledge about individual modalities is not the same. We know more about vision and hearing in birds compared with the infancy of our knowledge about taste and magnetoreception, and this is reflected in the level of detail applied to each sense. Nonetheless, Martin treats each modality similarly by providing background information on anatomy, neurobiology, and physiology. He then follows with examples of how the modality is used, often comparatively, among birds. For example, by comparing the optical anatomy of 2 species with similarly sized eyes, the Manx Shearwater (Puffinus puffinus) and the Rock Pidgeon (Columba livia), Martin shows how variations in the cornea, lens, and retinal ganglion cell density could lead to strikingly different perceptions of the same visual scene. Such an example illustrates how distantly related species with similar eye size can have distinct sensory worlds due to variation in eye anatomy. We anticipate that Volume 138, 2021, pp. 1–3 DOI: 10.1093/ornithology/ukab001