Browsing by Title
Now showing items 1866-1885 of 2493
-
Racial mixing in South African honeybees: the effects of genotype mixing on reproductive traits of workers
(Springer-Verlag, 2012)To test the hypothesis that the honeybee hybrid zone in South Africa is a tension zone due to increased reproductive conflict in colonies that contain both Apis mellifera capensis and Apis mellifera scutellata worker ... -
Raising the flag on marine alien fouling species
(REABIC, 2017)Harbours are known introduction foci of marine alien species. They act as recipients of new introductions and as sources for regional spread. We report on subtidal surveys of fouling communities from 14 harbours along the ... -
Range contraction to a higher elevation: the likely future of the montane vegetation in South Africa and Lesotho
(Springer, 2019)Global climate change is a major challenge for the future with serious potential impacts on biodiversity. Biodiversity in mountains is particularly vulnerable as many montane species are adapted to narrow microhabitats, ... -
Range expansions across ecoregions: interactions of climate change, physiology and genetic diversity
(John Wiley & Sons Ltd., 2014-01)Aim Climate change is expected to drive range shifts among a wide array of organisms. Non-indigenous species (NIS) provide a unique opportunity to observe the establishment of range boundaries in a way that cannot be ... -
Ranking of invasive spread through urban green areas in the world’s 100 most populous cities
(Springer, 2017)Urban landscapes are highly fragmented (leading to the extinction of native species) as well as transformed and disturbed (creating novel environments). Such conditions provide non-native species with opportunities to ... -
Rapid adaptation to invasive predators overwhelms natural gradients of intraspecific variation
(2020)Invasive predators can exert strong selection on native populations. If selection is strong enough, populations could lose the phenotypic variation caused by adaptation to heterogeneous environments. We compare frog tadpoles ... -
Rapid bioassessment of the effects of repeated rotenone treatments on invertebrate assemblages in the Rondegat River, South Africa
(NISC (Pty) Ltd and Taylor & Francis, 2015)The potential collateral effects of eradicating invasive fishes in streams necessitate the monitoring of invertebrate communities during treatment. In an environmental rehabilitation programme, non-native smallmouth bass ... -
Rapid cold-hardening in a Karoo beetle, Afrinus sp.
(The Royal Entomological Society, 2006)In the insect rapid cold-hardening response, survival at subzero temperatures is greatly improved by a brief pre-exposure at a milder temperature. It is predicted that insects with minimal cold tolerance capabilities living ... -
Rapid range expansion and community reorganization in response to warming
(Blackwell Publishing Ltd, 2008)Species ranges are expected to expand along their cooler boundaries in response to rising temperatures associated with current global climate change. However, this ‘fingerprint’ of climate change is yet to be assessed ... -
Rapid recovery of macroinvertebrates in a South African stream treated with rotenone
(Springer, 2019)South Africa’s Cape Fold Ecoregion supports a unique freshwater fish assemblage with many endemics. To mitigate impacts of alien invasive fishes on this unique assemblage, nature conservation authority CapeNature used ... -
Rapid response to shoot removal by the invasive wetland plant, alligator weed (Alternanthera philoxeroides)
(Elsevier B.V., 2007)Resprouting plants provide an interesting test to the generality of plant allometric relationships. The ability to rapidly resprout after disturbance also makes weeds more difficult to control. We performed a glasshouse ... -
Rapid shifts in the temperature dependence of locomotor performance in an invasive frog, Xenopus laevis, implications for conservation
(2020)Temperature is a critical abiotic factor impacting all aspects of the biology of organisms, especially in ectotherms. As such, it is an important determinant of the potential invasive ability of organisms and may limit ... -
A rapid survey of the invasive plant species in western Angola
(John Wiley & Sons, 2017)Angola is one of the most neglected African countries in terms of botanical research, in respect of both native and naturalized species. We conducted a rapid assessment of invasive plant species in western Angola during ... -
Rapid, field-deployable method for collecting and preserving plant metabolome for biochemical and functional characterization
(Creative Commons Attribution License, 2018)Study of plant metabolome is a growing field of science that catalogs vast biochemical and functional diversity of phytochemicals. However, collecting and storing samples of plant metabolome, sharing these samples across ... -
Rate dynamics of ectotherm responses to thermal stress
(The Royal Society Publishing, 2019)Critical thermal limits (CTLs) show much variation associated with the experimental rate of temperature change used in their estimation. Understanding the full range of variation in rate effects on CTLs and their underlying ... -
Rates and causes of mortality in Endangered African wild dogs Lycaon
(Fauna & Flora International, UK, 2007-05)Effective species conservation depends upon correctly identifying the threats that cause decline or hinder recovery. Because estimates of the relative viability of different populations of Endangered African wild dogs ... -
Re-establishment of Protea repens after clearing invasive Acacia saligna: Consequences of soil legacy effects and native nitrophilic weedy species
(Elsevier B.V., 2018)Invasive Australian acacias can alter soil chemistry and microbial communities in areas they invade. After clearing invasive acacias, these changes can persist, and previously invaded areas can become dominated by nitrophilic ... -
Re-evaluation of a riparian restoration experiment in the Western Cape Province: Status 8 years down the line
(Elsevier, 2007-04)In 1998, a study was initiated to assess the relative effectiveness of three different sowing treatments for reducing soil erosion and restoring indigenous riparian vegetation cover after alien clearing in the Western Cape. ...