Invasive alien species are a major threat to native insular species. Eradicating invasive mammals from islands is a feasible and proven approach to prevent biodiversity loss. We developed a conceptual framework to identify globally important islands for invasive mammal eradications to prevent imminent extinctions of highly threatened species using biogeographic and technical factors, plus a novel approach to consider socio-political feasibility. We applied this framework using a comprehensive dataset describing the distribution of 1,184 highly threatened native vertebrate species (i.e. those listed as Critically Endangered or Endangered on the IUCN Red List) and 184 non-native mammals on 1,279 islands worldwide. Based on extinction risk, irreplaceability, severity of impact from invasive species, and technical feasibility of eradication, we identified and ranked 292 of the most important islands where eradicating invasive mammals would benefit highly threatened vertebrates. When socio-political feasibility was considered, we identified 169 of these islands where eradication planning or operation could be initiated by 2020 or 2030 and would improve the survival prospects of 9.4% of the Earth’s most highly threatened terrestrial insular vertebrates (111 of 1,184 species). Of these, 107 islands were in 34 countries and territories and could have eradication projects initiated by 2020. Concentrating efforts to eradicate invasive mammals on these 107 islands would benefit 151 populations of 80 highly threatened vertebrates and make a major contribution towards achieving global conservation targets adopted by the world’s nations.
Aim To create a map of bird species richness (BSR) in East Asia and to examine the effect of area, isolation, primary productivity, topographic heterogeneity, and human population density on BSR. Location East Asia (from 70° E to 180° E longitude), including the eastern half of the Palaearctic Region, the entire Oriental Region, and the entire Wallacea Subregion. Methods The breeding ranges of 2406 terrestrial bird species were mapped and overlaid to create a species richness map. The BSR map was transformed into a 100 × 100 km quadrat system, and BSR was analysed in relation to land area, average normalized difference vegetation index (NDVI), elevation range, and average population density. Results In general, BSR declined from the Tropics to the Arctic. In mainland East Asia, however, BSR was highest around the Tropic of Cancer, and fluctuated between 30° and 50° N. Islands had lower BSR than adjacent mainland areas. The NDVI was strongly positively correlated with BSR in mainland areas and on islands. For mainland areas, NDVI explained 65% of the BSR variation, and topographic heterogeneity explained an additional 6% in ordinary least‐squares regression. On islands, NDVI explained 66% of BSR variation, island area explained 13%, and distance to mainland accounted for 1%. Main conclusions In East Asia, we suggest that primary productivity is the key factor underpinning patterns of BSR. Primary productivity sets the upper limits of the capacity of habitats to support bird species. In isolated areas such as islands and peninsulas, however, BSR might not reach the richness limits set by primary productivity because the degree of isolation and area size also can affect species richness. Other factors, such as spatial heterogeneity, biotic interactions, and perturbations, may also affect species richness. However, their effects are secondary and are not as strong as primary productivity, isolation, and area size.
Abstract.Apart from SERPINB2 and SERPINB5, the roles of the remaining 13 members of the human SERPINB family in cancer metastasis are still unknown. In the present study, we demonstrated that most of these genes are differentially expressed in tumor tissues compared to matched normal tissues from lung or breast cancer patients. Overexpression of each SERPINB gene effectively suppressed the invasiveness and motility of malignant cancer cells. Among all of the genes, the SERPINB1, SERPINB5 and SERPINB7 genes were more potent, and the inhibitory effect was further enhanced by co-expression of any two of them. In addition, single treatment of the synthetic peptides corresponding to the P5-P5' sequences of the reactive center loop (RCL) of SERPINB1, SERPINB5 or SERPINB7 markedly suppressed the invasive and migratory properties of the cancer cells in a dose-dependent manner. More significantly, combination treatment of these peptides in cancer cells further improved the suppressive effect by 20-40%. Here, we determined the expression of all SERPINB family members in lung and breast cancer patients, and identified those members with potent inhibitory ability toward invasion and migration, and designed RCL-derived peptides to suppress the malignancy of cancer cells. Forced re-expression of these anti-invasive SERPINB genes or application of the SERPINB RCL-peptides may provide a reasonable strategy against lethal cancer metastasis. IntroductionCancer metastasis is the leading cause of morbidity and mortality in cancer patients. It is a highly complex process, including cell detachment, migration, invasion, circulation in blood vessels, adhesion, colonization at other sites and formation of secondary tumors (1). Prior to tumor cell detachment from the primary site, which leads to cell migration and invasion in the metastasis process, the extracellular matrix (ECM) microenvironment must be degraded by proteases, such as urokinase plasminogen activator (uPA), uPA receptor (uPAR) and the plasmin network (2,3) and matrix metalloproteinases (MMPs) (4). On the other hand, protease inhibitors negatively regulate the proteolysis process in cancer metastasis, e.g. plasminogen activator inhibitors (PAIs), PAI-1 (SERPINE1) and PAI-2 (SERPINB2) against uPA/uPAR/plasmin network and the tissue inhibitor of matrix metalloproteinases (TIMPs), TIMP-1 to TIMP-4 against MMPs.Serine protease inhibitors (serpins) regulate many physiological processes, such as blood coagulation, fibrinolysis, inflammation, complement activation and cell migration (5). Based on their phylogenic relationships, the superfamily is divided into 16 different clades (A-P), in which human serpins are the first 9 clades (A-I) (6). The clade B serpins (SERPINB family) is the largest one within the human serpin superfamily. It contains 13 genes located on chromosome 6p25 (SERPINB1, SERPINB6 and SERPINB9) and 18q21 (the remaining members of the family). Unlike circulating serpins, the SERPINB family genes lack the N and C terminus extension regions common to other serpin...
Offspring often compete over limited available resources. Such sibling competition may be detrimental to parents both because it entails wasted expenditure and because it allows stronger offspring to obtain a disproportionate share of resources. We studied nestling conflict over food and its resolution in a joint-nesting species of bird, the Taiwan yuhina (Yuhina brunneiceps). We show that adult yuhinas coordinate their feeding visits, and that this coordination limits competition among nestlings, leading to a 'fairer' division of resources. Transponder identification and video-recording systems were used to observe adult feeding and nestling begging behaviours. We found that: (i) yuhinas feed nestlings more often in large parties than in small parties; (ii) feeding events occurred nonrandomly in bouts of very short intervals; and (iii) food distribution among nestlings was more evenly distributed, and fewer nestlings begged, during large-party feeding bouts compared with small-party feeding bouts. To our knowledge, this is the first study in a cooperative breeding species showing that adults can influence food allocation and competition among nestlings by coordinating their feeding visits. Our results confirm the hypothesis that the monopolizability of food affects the intensity of sibling competition, and highlight the importance of understanding the temporal strategies of food delivery.
Aim To examine the species richness of breeding birds along a local elevational gradient and to test the following assumptions of the energy limitation hypothesis:(1) the energy flux through birds is positively correlated with above-ground net primary productivity, (2) bird density is positively correlated with total energy flux, and (3) bird species richness is positively correlated with bird density.Location An elevational gradient from 1400 to 3700 m on Mt. Yushan, the highest mountain in Taiwan (23 ° 28 ′ 30 ″ N, 120 ° 54 ′ 00 ″ E), with a peak of 3952 m a.s.l. MethodsWe established 50 sampling stations along the elevational gradient. From March to July 1992, we estimated the density of each bird species using the variable circular-plot method. Above-ground net primary productivity was modelled using monthly averages from weather data for the years 1961-90. ResultsBird species richness had a hump-shaped relationship with elevation and with net primary productivity. Bird energy flux was positively correlated with net primary productivity and bird species richness was positively correlated with bird density. The relationship between bird density and energy flux was hump-shaped, which does not support one assumption of the energy limitation hypothesis. Main conclusionsThe results supported two essential assumptions of the energy limitation hypothesis. However, when energy availability exceeded a certain level, it could decrease species richness by increasing individual energy consumption, which reduced bird density. Thus, energy availability is a primary factor influencing bird species richness at this scale, but other factors, such as body size, could also play important roles.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.