47 research outputs found
Biodiversity Loss and the Taxonomic Bottleneck: Emerging Biodiversity Science
Human domination of the Earth has resulted in dramatic changes to global and local patterns of biodiversity. Biodiversity is critical to human sustainability because it drives the ecosystem services that provide the core of our life-support system. As we, the human species, are the primary factor leading to the decline in biodiversity, we need detailed information about the biodiversity and species composition of specific locations in order to understand how different species contribute to ecosystem services and how humans can sustainably conserve and manage biodiversity. Taxonomy and ecology, two fundamental sciences that generate the knowledge about biodiversity, are associated with a number of limitations that prevent them from providing the information needed to fully understand the relevance of biodiversity in its entirety for human sustainability: (1) biodiversity conservation strategies that tend to be overly focused on research and policy on a global scale with little impact on local biodiversity; (2) the small knowledge base of extant global biodiversity; (3) a lack of much-needed site-specific data on the species composition of communities in human-dominated landscapes, which hinders ecosystem management and biodiversity conservation; (4) biodiversity studies with a lack of taxonomic precision; (5) a lack of taxonomic expertise and trained taxonomists; (6) a taxonomic bottleneck in biodiversity inventory and assessment; and (7) neglect of taxonomic resources and a lack of taxonomic service infrastructure for biodiversity science. These limitations are directly related to contemporary trends in research, conservation strategies, environmental stewardship, environmental education, sustainable development, and local site-specific conservation. Today’s biological knowledge is built on the known global biodiversity, which represents barely 20% of what is currently extant (commonly accepted estimate of 10 million species) on planet Earth. Much remains unexplored and unknown, particularly in hotspots regions of Africa, South Eastern Asia, and South and Central America, including many developing or underdeveloped countries, where localized biodiversity is scarcely studied or described. ‘‘Backyard biodiversity’’, defined as local biodiversity near human habitation, refers to the natural resources and capital for ecosystem services at the grassroots level, which urgently needs to be explored, documented, and conserved as it is the backbone of sustainable economic development in these countries. Beginning with early identification and documentation of local flora and fauna, taxonomy has documented global biodiversity and natural history based on the collection of ‘‘backyard biodiversity’’ specimens worldwide. However, this branch of science suffered a continuous decline in the latter half of the twentieth century, and has now reached a point of potential demise. At present there are very few professional taxonomists and trained local parataxonomists worldwide, while the need for, and demands on, taxonomic services by conservation and resource management communities are rapidly increasing. Systematic collections, the material basis of biodiversity information, have been neglected and abandoned, particularly at institutions of higher learning. Considering the rapid increase in the human population and urbanization, human sustainability requires new conceptual and practical approaches to refocusing and energizing the study of the biodiversity that is the core of natural resources for sustainable development and biotic capital for sustaining our life-support system. In this paper we aim to document and extrapolate the essence of biodiversity, discuss the state and nature of taxonomic demise, the trends of recent biodiversity studies, and suggest reasonable approaches to a biodiversity science to facilitate the expansion of global biodiversity knowledge and to create useful data on backyard biodiversity worldwide towards human sustainability
Hyperspectral phasor analysis enables multiplexed 5D in vivo imaging
Time-lapse imaging of multiple labels is challenging for biological imaging as noise, photobleaching and phototoxicity compromise signal quality, while throughput can be limited by processing time. Here, we report software called Hyper-Spectral Phasors (HySP) for denoising and unmixing multiple spectrally overlapping fluorophores in a low signal-to-noise regime with fast analysis. We show that HySP enables unmixing of seven signals in time-lapse imaging of living zebrafish embryos
Quantifying the impacts of defaunation on natural forest regeneration in a global meta-analysis
Intact forests provide diverse and irreplaceable ecosystem services that are critical to human well-being, such as carbon storage to mitigate climate change. However, the ecosystem functions that underpin these services are highly dependent on the woody vegetation-animal interactions occurring within forests. While vertebrate defaunation is of growing policy concern, the effects of vertebrate loss on natural forest regeneration have yet to be quantified globally. Here we conduct a meta-analysis to assess the direction and magnitude of defaunation impacts on forests. We demonstrate that real-world defaunation caused by hunting and habitat fragmentation leads to reduced forest regeneration, although manipulation experiments provide contrasting findings. The extirpation of primates and birds cause the greatest declines in forest regeneration, emphasising their key role in maintaining carbon stores, and the need for national and international climate change and conservation strategies to protect forests from defaunation fronts as well as deforestation fronts
Cross-scale habitat structure driven by coral species composition on tropical reefs
The availability of habitat structure across spatial scales can determine ecological organization and resilience. However, anthropogenic disturbances are altering the abundance and composition of habitat-forming organisms. How such shifts in the composition of these organisms alter the physical structure of habitats across ecologically important scales remains unclear. At a time of unprecedented coral loss and homogenization of coral assemblages globally, we investigate the inherent structural complexity of taxonomically distinct reefs, across fve ecologically relevant scales of measurement (4–64cm). We show that structural complexity was infuenced by coral species composition, and was not a simple function of coral cover on the studied reefs. However, inter-habitat variation in structural complexity changed with scale. Importantly, the scales at which habitat structure was available also varied among habitats. Complexity at the smallest, most vulnerable scale (4cm) varied the most among habitats, which could have inferences for as much as half of all reef fshes which are small-bodied and refuge dependent for much of their lives. As disturbances continue and species shifts persist, the future of these ecosystems may rely on a greater concern for the composition of habitat-building species and prioritization of particular confgurations for protection of maximal cross-scale habitat structural complexity
Vibratory conveyors
A review of the previous work on the mechanics of vibratory conveying is given., It is found that several theoretical studies have been made in the past but the predictions of the theories and the comparisons of these' with experimental results have only been applicable to a very limited range of the relevant variables. In the present work, a theoretical analysis is described which enables the mean conveying velocity of a component on a conventional vibratory conveyor to be determined for'a wide range of the relevant variables. Since an alternative method of vibration is discussed, "conventional" refers' to vibratory conveyors which are commercially available. The results of this theory are compared with the results of experimental work conducted on apparatus specially designed for the purpose. Within practical limits, good agreement is obtained. From this work it is concluded that fundamental limitations eXist in conventional vibratory conveying, the most important of which are that the conveying velocity is very sensitive to changes in the coefficient of friction between the component and the track and for low coefficients of friction, the conveying velocity for steady conveying is inadequate. • A further analysis is then described which considers the mechanics of Vibratory conveying where a phase difference exists between the normal and parallel motions of the track, (known as "out of phase" conveying). Again, within certain limits, the new theory is in good agreement with experimental results. It is apparent from this work that with the correct phase relation$hip between the two components of vibration, definite practical advantages exist over conventional conveying. With "out of phase" conveying, the component velocity is virtually independent of the nature of the component and track materials and conveying velocities significantly higher than those obtainable on a conventional vibratory conveyor axe possible. Further, with this vibration system, components can be conveyed separately and without erratic motion up an inclined track. A practical method of obtaining an "out of phase" vibration on the track of a vibratory bowl feeder is suggested. The results of performance tests on two commercially available vibratory bowl feeders with conventional drives are presented and it is shown that in both cases their performance is very sensitive to changes in the bowl load. A method for reducing this effect by re-tuning the bowl spring support system is demonstrated. Some suggestions for improving the performance of conventional bowl feeders are discussed which include details of how the track angle, vibration. angle, track material and suspension spring stiffness should be determined