549 research outputs found
The diverse nature of island isolation and its effect on land bridge insular faunas
Aim:
Isolation is a key factor in island biology. It is usually defined as the distance to the geographically nearest mainland, but many other definitions exist. We explored how testing different isolation indices affects the inference of impacts of isolation on faunal characteristics. We focused on land bridge islands and compared the relationships of many spatial and temporal (i.e., through time) isolation indices with communityâ, populationâ and individualâlevel characteristics (species richness, population density and body size, respectively).
Location:
Aegean Sea islands, Greece.
Time period:
Current.
Taxon:
Many animal taxa.
Methods:
We estimated 21 isolation indices for 205 islands and recorded species richness data for 15 taxa (invertebrates and vertebrates). We obtained body size data for seven lizard species and population density data for three. We explored how well indices predict each characteristic, in each taxon, by conducting a series of ordinary least squares regressions (controlling for island area when needed) and a metaâanalysis.
Results:
Isolation was significantly (and negatively) associated with species richness in 10 of 15 taxa. It was significantly (and positively) associated with body size in only one of seven species and was not associated with population density. The effect of isolation on species richness was much weaker than that of island area, regardless of the index tested. Spatial indices generally outâperformed temporal indices, and indices directly related to the mainland outâperformed those related mainly to neighbouring islands. No index was universally superior to others, including the distance to the geographically nearest mainland.
Main conclusions:
The choice of index can alter our perception of the impacts of isolation on biological patterns. The nearly automatic, ubiquitous use of distance to the geographically nearest mainland misrepresents the complexity of the effects of isolation. We recommend the simultaneous testing of several indices that represent different aspects of isolation, in order to produce more constructive and thorough investigations and avoid imprecise inference
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Comparison of herbarium label data and published medicinal use: herbaria as an underutilized source of ethnobotanical information
The use of herbarium specimens as vouchers to support ethnobotanical surveys is well established. However,
herbaria may be underutilized resources for ethnobotanical research that depends on the analysis of large datasets compiled across multiple sites. Here, we compare two medicinal use datasets, one sourced from
published papers and the other from online herbaria to determine whether herbarium and published data
are comparable and to what extent herbarium specimens add new data and fill gaps in our knowledge of
geographical extent of plant use. Using Brazilian legumes as a case study, we compiled 1400 use reports from
105 publications and 15 Brazilian herbaria. Of the 319 species in 107 genera with cited medicinal uses, 165
(51%) were recorded only in the literature and 55 (17%) only on herbarium labels. Mode of application,
plant part used, or therapeutic use was less often documented by herbarium specimen labels (17% with
information) than publications (70%). However, medicinal use of 21 of the 128 species known from only
one report in the literature was substantiated from independently collected herbarium specimens, and 58
new therapeutic applications, 25 new plant parts, and 16 new modes of application were added for species
known from the literature. Thus, when literature reports are few or information-poor, herbarium data can
both validate and augment these reports. Herbarium data can also provide insights into the history and
geographical extent of use that are not captured in publications
Ethnobotanical research under the COVID-19 pandemic: assessing a remote method for documenting Indigenous plant-related knowledge
NWOVI.Veni.191T.007Descriptive and Comparative Linguistic
Accuracy and repeatability of wrist joint angles in boxing using an electromagnetic tracking system
© 2019, The Author(s). The hand-wrist region is reported as the most common injury site in boxing. Boxers are at risk due to the amount of wrist motions when impacting training equipment or their opponents, yet we know relatively little about these motions. This paper describes a new method for quantifying wrist motion in boxing using an electromagnetic tracking system. Surrogate testing procedure utilising a polyamide hand and forearm shape, and in vivo testing procedure utilising 29 elite boxers, were used to assess the accuracy and repeatability of the system. 2D kinematic analysis was used to calculate wrist angles using photogrammetry, whilst the data from the electromagnetic tracking system was processed with visual 3D software. The electromagnetic tracking system agreed with the video-based system (paired t tests) in both the surrogate ( 0.9). In the punch testing, for both repeated jab and hook shots, the electromagnetic tracking system showed good reliability (ICCs > 0.8) and substantial reliability (ICCs > 0.6) for flexionâextension and radial-ulnar deviation angles, respectively. The results indicate that wrist kinematics during punching activities can be measured using an electromagnetic tracking system
Detailed α-decay study of 180Tl
International audienceA detailed -decay spectroscopy study of has been performed at ISOLDE (CERN). -selective ionization by the Resonance Ionization Laser Ion Source (RILIS) coupled to mass separation provided a high-purity beam of . Fine-structure decays to excited levels in the daughter were identified and an -decay scheme of was constructed based on an analysis of - and -- coincidences. Multipolarities of several -ray transitions deexciting levels in were determined. Based on the analysis of reduced -decay widths, it was found that all decays are hindered, which signifies a change of configuration between the parent and all daughter states
Seabird species vary in behavioural response to drone census
This is the final version of the article. Available from the publisher via the DOI in this record.Unmanned aerial vehicles (UAVs) provide an opportunity to rapidly census wildlife in remote areas while removing some of the hazards. However, wildlife may respond negatively to the UAVs, thereby skewing counts. We surveyed four species of Arctic cliff-nesting seabirds (glaucous gull Larus hyperboreus, Iceland gull Larus glaucoides, common murre Uria aalge and thick-billed murre Uria lomvia) using a UAV and compared censusing techniques to ground photography. An average of 8.5% of murres flew off in response to the UAV, but >99% of those birds were non-breeders. We were unable to detect any impact of the UAV on breeding success of murres, except at a site where aerial predators were abundant and several birds lost their eggs to predators following UAV flights. Furthermore, we found little evidence for habituation by murres to the UAV. Most gulls flew off in response to the UAV, but returned to the nest within five minutes. Counts of gull nests and adults were similar between UAV and ground photography, however the UAV detected up to 52.4% more chicks because chicks were camouflaged and invisible to ground observers. UAVs provide a less hazardous and potentially more accurate method for surveying wildlife. We provide some simple recommendations for their use.We thank T. Leonard and the Seabird Ecological Reserves Advisory Committee for permission to work at Witless
Bay, the Canadian Wildlife Service for permits to work at Newfoundland and Nunavut and the Government of
Nunavut for permits to work in Nunavut. Newfoundland and Labrador Murre Fund, Bird Studies Canada and
the Molson Foundation directly funded the work. An NSERC Discovery Grant, the Canada Research Chair in
Arctic Ecology and Polar Continental Shelf Project also helped fund the project. We thank T. Burke, G. Sorenson,
T. Lazarus and M. Guigueno for their help and J. Nakoolak for keeping us safe from bear
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