State of the world's birds

We present an overview of the global spatiotemporal distribution of avian biodiversity, changes in our knowledge of that biodiversity, and the extent to which it is imperilled. Birds are probably the most completely inventoried large taxonomic class of organisms, permitting a uniquely detailed understanding of how the Anthropocene has shaped their distributions and conservation status in space and time. We summarize the threats driving changes in bird species richness and abundance, highlighting the increasingly synergistic interactions between threats such as habitat loss, climate change, and overexploitation. Many metrics of avian biodiversity are exhibiting globally consistent negative trends, with the International Union for Conservation of Nature's Red List Index showing a steady deterioration in the conservation status of the global avifauna over the past three decades. We identify key measures to counter this loss of avian biodiversity and associated ecosystem services, which will necessitate increased consideration of the social context of bird conservation interventions in order to deliver positive transformative change for nature

Predicting species invasion : global change and the non-native trees of Southern Africa

Abstract: Please refer to full text to view abstractD.Phil. (Botany

Invasion of alien species on Robben Island : causes and impacts on phylogenetic diversity of native plant communities

M.Sc.Invasive species are a considerable threat to ecosystems globally, especially on islands where species diversity can be relatively low. Understanding the drivers of invasion is the first step towards an adequate management plan. Although Darwin’s naturalisation hypothesis has fuelled our understanding in this regard, several studies provided mixed results, suggesting that invasion success might be context-dependent. The main objectives of this study are two-fold: (1) testing Darwin hypothesis on Robben Island, and (2) investigating the relative role of invasive alien plants on phylogenetic diversity (PD) loss in native community. I sampled extensively the flora of the island, and using a Bayesian analysis, I reconstructed its phylogeny based on two plastid DNA loci, rbcLa and matK. I also surveyed a total of 127 plots of 50 x 50 m (i.e. local communities) where species presence/absence was recorded. Analysing phylogenetic patterns of the native and invasive floras at both regional (phylogeny level) and smaller scales (plots level), I found that invasive species are, on average, more distantly related to the native communities, giving strong support to the hypothesis tested. Furthermore I found that native communities have accumulated lower PD than alien communities; and that local communities are more overdispersed than expected. These findings suggest that competitive interactions might be the major ecological forces shaping plant communities, with the possibility of alien being higher competitors than native, and therefore decreasing native plant diversity. The implications of these findings for the recovery of native plants are also discussed. Key words: Invasion biology - Darwin’s naturalisation hypothesis - Phylogenetic diversity - Community structure - Conservation - Robben Island, South Africa

Phylogenetically diverse native systems are more resistant to invasive plant species on Robben Island, South Africa

Alien invasive species are problematic both economically and ecologically, particularly on islands. As such, understanding how they interact with their environment is necessary to inform invasive species management. Here, we ask the following questions: What are the main functional traits that correlate with invasion success of alien plants on Robben Island? How does phylogenetic structure shape biotic interactions on the island? Using multiple approaches to explore these questions, we found that alien invasive species flower later during the year and for longer period, although flowering phenology was sensitive to alternative starting date. Additionally, we observed that alien invasive species are mostly abiotically pollinated and are generally hermaphroditic whilst their native counterparts rely on biotic pollinators, flower earlier and are generally dioecious, suggesting that alien invasive and native species use different ecological niches. Furthermore, we found a facilitative interaction between an alien invasive legume and other invasive plants as predicted by the invasional meltdown hypothesis, but this does not influence the phylogenetic structure of plant communities. Finally, phylogenetically diverse set of native species are less receptive to alien invasive species. Collectively, our findings reveal how biotic interactions and phylogenetic relatedness structure alien invasive-native co-existence.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Data from: Revisiting Darwin’s naturalization conundrum: explaining invasion success of non-native trees and shrubs in southern Africa

1. Invasive species are detrimental ecologically and economically. Their negative impacts in Africa are extensive and call for a renewed commitment to better understand the correlates of invasion success. 2. Here, we explored several putative drivers of species invasion among woody non-native trees and shrubs in southern Africa, a region of high floristic diversity. We tested for differences in functional traits between plant categories using a combination of phylogenetic independent contrasts and a simulation-based phylogenetic anova. 3. We found that non-native species generally have longer flowering duration compared with native species and are generally hermaphroditic, and their dispersal is mostly abiotically mediated. We also revealed that non-native trees and shrubs that have become invasive are less closely related to native trees and shrubs than their non-invasive non-native counterparts. Non-natives that are more closely related to the native species pool may be more likely to possess traits suited to the new environment in which they find themselves and thus have greater chance of establishment. However, successful invaders are less closely related to the native pool, indicating evidence for competitive release or support for the vacant niche theory. 4. Synthesis. Non-native trees and shrubs in southern Africa are characterized by a suite of traits, including long flowering times, a hermaphroditic sexual system and abiotic dispersal, which may represent important adaptations promoting establishment. We suggest that differences in the evolutionary distances separating the native species pool from invasive and non-invasive species might help resolve Darwin's naturalization conundrum

Phylogenetic tree

Phylogeny of southern African trees and shrubs specie

Table S1

Table S

Table S2

Trait database used in this analysi

Ten years of barcoding at the African Centre for DNA barcoding

The African Centre for DNA Barcoding (ACDB) was established in 2005 as part of a global initiative to accurately and rapidly survey biodiversity using short DNA sequences. The mitochondrial cytochrome c oxidase 1 gene (CO1) was rapidly adopted as the de facto barcode for animals. Following the evaluation of several candidate loci for plants, the Plant Working Group of the Consortium for the Barcoding of Life in 2009 recommended that the two plastid genes, rbcLa and matK, be adopted as core DNA barcodes for terrestrial plants. To date, numerous studies continue to test the discriminatory power of these markers across various plant lineages. Over the past decade, we at the African Centre for DNA Barcoding, have used these core DNA barcodes to generate a barcode library for southern Africa. To date, the ACDB has contributed more than 21 000 plant barcodes and over 3 000 CO1 barcodes for animals to the Barcode of Life Database (BOLD). Building upon this effort, we at the ACDB have addressed questions related to community assembly, biogeography, phylogenetic diversification, and invasion biology. Collectively, our work demonstrates the diverse applications of DNA barcoding in ecology, systematics, evolutionary biology, and conservation.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Addressing the Biodiversity Paradox: Mismatch between the Co-Occurrence of Biological Diversity and the Human, Financial and Institutional Resources to Address Its Decline

Pressures are mounting for the adoption of a Global Biodiversity Framework that transforms conservation and sustainable use efforts worldwide. Underlying this challenge is the biodiversity paradox: biological diversity predominantly concentrates in the tropics, while human, institutional, and financial resources are primarily located at higher latitudes both north and south. Addressing the biodiversity paradox requires the expansion and mobilization of human, institutional and financial resources around the world. We outline a model championed by the IUCN Species Survival Commission (SSC) that builds on the Species Conservation Cycle (Assess-Plan-Act-Network-Communicate) and recognizes that most conservation action occurs at the national or local level. Various strategies are applied to this end by the partners of Reverse the Red, a global movement that ignites strategic cooperation and science-based action to ensure the survival of wild species and ecosystems. The SSC contributes to Reverse the Red through two primary strategies: National Species Specialist Groups and Centers for Species Survival. By building on existing expert networks and catalyzing efforts with established local institutions, we aim to significantly expand capacity to implement conservation action at the national level and reverse the negative trends indicated by the IUCN Red List of Threatened Species and the Red List of Ecosystems