scholarly journals Complex Human-Shark Conflicts Confound Conservation Action

2021 ◽  
Vol 2 ◽  
Author(s):  
Colin A. Simpfendorfer ◽  
Michelle R. Heupel ◽  
Dave Kendal
Keyword(s):  
Human Populations ◽  
Shark Species ◽  
Conservation Action ◽  
Economic Implications ◽  
Fish Stocks ◽  
Functional Roles ◽  
Important Prey ◽  
Values And Beliefs ◽  
Human Conflict ◽  
Future Work

Human-wildlife conflicts are a growing phenomenon globally as human populations expand and wildlife interactions become more commonplace. While these conflicts have been well-defined in terrestrial systems, marine forms are less well-understood. As concerns grow for the future of many shark species it is becoming clear that a key to conservation success lies in changing human behaviors in relation to sharks. However, human-shark conflicts are multidimensional, each with different ecological, social and economic implications. Sharks have functional roles as occasional predators of humans and competitors with humans for fish stocks. In addition, and unlike most terrestrial predators, sharks are also important prey species for humans, being a source of animal protein and other products taken in fisheries. These functional roles are complex and often inter-dependent which can lead to multiple kinds of conflict. Shark management for conservation and human safety is also leading to conflict between different groups of people with different values and beliefs, demonstrating that human wildlife conflict can be a proxy for human-human conflict in the marine domain. Sharks are iconic species in society, being both feared and revered. As such human beliefs, attitudes and perceptions play key roles that underpin much human-shark conflict and future work to understanding these will contribute significantly to solutions that reduce conflict and hence improve conservation outcomes.

scholarly journals Genetic and linguistic histories in Central Asia inferred using approximate Bayesian computations

2017 ◽  
Vol 284 (1861) ◽  
pp. 20170706 ◽  
Author(s):  
Valentin Thouzeau ◽  
Philippe Mennecier ◽  
Paul Verdu ◽  
Frédéric Austerlitz
Keyword(s):  
Central Asia ◽  
Linguistic Diversity ◽  
Past History ◽  
Genetic Data ◽  
Human Populations ◽  
Language Diversity ◽  
Methodological Framework ◽  
The Past ◽  
Approximate Bayesian ◽  
Future Work

Linguistic and genetic data have been widely compared, but the histories underlying these descriptions are rarely jointly inferred. We developed a unique methodological framework for analysing jointly language diversity and genetic polymorphism data, to infer the past history of separation, exchange and admixture events among human populations. This method relies on approximate Bayesian computations that enable the identification of the most probable historical scenario underlying each type of data, and to infer the parameters of these scenarios. For this purpose, we developed a new computer program PopLingSim that simulates the evolution of linguistic diversity, which we coupled with an existing coalescent-based genetic simulation program, to simulate both linguistic and genetic data within a set of populations. Applying this new program to a wide linguistic and genetic dataset of Central Asia, we found several differences between linguistic and genetic histories. In particular, we showed how genetic and linguistic exchanges differed in the past in this area: some cultural exchanges were maintained without genetic exchanges. The methodological framework and the linguistic simulation tool developed here can be used in future work for disentangling complex linguistic and genetic evolutions underlying human biological and cultural histories.

scholarly journals Elevated nonlinearity as indicator of transition to overexploitation in fish stocks

2016 ◽  
Author(s):  
Vasilis Dakos ◽  
Sarah M. Glaser ◽  
Chih-hao Hsieh ◽  
George Sugihara
Keyword(s):  
Trophic Structure ◽  
Type Model ◽  
Western Atlantic ◽  
Economic Implications ◽  
Fish Stocks ◽  
As Species ◽  
Abrupt Changes ◽  
Risk Of Extinction ◽  
Statistical Metrics

AbstractEcosystems may experience abrupt changes such as species extinctions, reorganisations of trophic structure, or transitions from stable population dynamics to strongly irregular fluctuations. Although most of these changes have important ecological and at times economic implications, they remain notoriously difficult to detect in advance. Here, we use a Ricker-type model to simulate the transition of a hypothetical stable fisheries population either to irregular boom-bust dynamics or to overexploitation. Our aim is to infer the risk of extinction in these two scenarios by comparing changes in variance, autocorrelation, and nonlinearity between unexploited and exploited populations. We find that changes in these statistical metrics reflect the risk of extinction but depend on the type of dynamical transition. Variance and nonlinearity increase similarly in magnitude along both transitions. In contrast, autocorrelation depends strongly on the presence of underlying oscillating dynamics. We also compare our theoretical expectations to indicators measured in long-term datasets of fish stocks from the California Cooperative Oceanic Fisheries Investigation in the Eastern Pacific and from the Northeast Shelf in the Western Atlantic. Our results suggest that elevated variance and nonlinearity could be potentially used to rank exploited fish populations according to their risk of extinction.

Beyond Global Englishes: Teaching English as a Dynamic Language

RELC Journal ◽  
2018 ◽  
Vol 49 (1) ◽  
pp. 36-57 ◽  
Author(s):  
Ahmar Mahboob
Keyword(s):  
Language Proficiency ◽  
Native Speaker ◽  
Language Variation ◽  
World Englishes ◽  
Endangered Languages ◽  
Teaching English ◽  
Economic Implications ◽  
Dynamic Language ◽  
Future Work ◽  
Further Development

Currently, a growing number of teaching approaches focus on aspects of variation in language (e.g. English as a Lingua Franca (ELF), World Englishes, English for Specific Purposes (ESP), genre theories, etc.); however, each of these approaches tends to focus on particular (specific) aspects of language variation and do not fully account for the range or dynamicity of linguistic variations. This article, based on a discussion of language variation, proposes a model of language proficiency that considers the dynamic nature of language variation and is not dependent on static (native-speaker defined) norms of language. Using the Dynamic Approach to Language Proficiency as a model of language proficiency and grounded in understandings of language variation, this article introduces the concept of Teaching English as a Dynamic Language (TEDL). The article includes evidence for the need to develop such a model and also points out ways in which current and future work can contribute to further development of this approach. Finally, the article also identifies some socio-economic implications of this work and explicitly supports the need to recognize and empower local (including endangered) languages through TEDL.

Measuring inequality

2019 ◽  
Vol 35 (3) ◽  
pp. 368-395 ◽  
Author(s):  
Thomas McGregor ◽  
Brock Smith ◽  
Samuel Wills
Keyword(s):  
Social Welfare ◽  
Social Welfare Function ◽  
Economic Implications ◽  
Recent Advances ◽  
Variable Population ◽  
Future Work

Abstract Inequality is important, both for its own sake and for its political, social, and economic implications. However, measuring inequality is not straightforward, as it requires decisions to be made on the variable, population, and distributional characteristics of interest. These decisions will naturally influence the conclusions that are drawn so they must be closely linked to an underlying purpose, which is ultimately defined by a social welfare function. This paper outlines important considerations when making each of these decisions, before surveying recent advances in measuring inequality and suggesting avenues for future work.

scholarly journals Origins and Evolutionary Patterns of the 1.688 Satellite DNA Family in Drosophila Phylogeny

2020 ◽  
Vol 10 (11) ◽  
pp. 4129-4146
Author(s):  
Leonardo G. de Lima ◽  
Stacey L. Hanlon ◽  
Jennifer L. Gerton
Keyword(s):  
Repetitive Sequences ◽  
Specific Pattern ◽  
Evolutionary Patterns ◽  
Satellite Dnas ◽  
Evolutionary Pattern ◽  
Functional Roles ◽  
Drosophila Phylogeny ◽  
Species Specific ◽  
Future Work ◽  
Eukaryotic Genomes

Satellite DNAs (satDNAs) are a ubiquitous feature of eukaryotic genomes and are usually the major components of constitutive heterochromatin. The 1.688 satDNA, also known as the 359 bp satellite, is one of the most abundant repetitive sequences in Drosophila melanogaster and has been linked to several different biological functions. We investigated the presence and evolution of the 1.688 satDNA in 16 Drosophila genomes. We find that the 1.688 satDNA family is much more ancient than previously appreciated, being shared among part of the melanogaster group that diverged from a common ancestor ∼27 Mya. We found that the 1.688 satDNA family has two major subfamilies spread throughout Drosophila phylogeny (∼360 bp and ∼190 bp). Phylogenetic analysis of ∼10,000 repeats extracted from 14 of the species revealed that the 1.688 satDNA family is present within heterochromatin and euchromatin. A high number of euchromatic repeats are gene proximal, suggesting the potential for local gene regulation. Notably, heterochromatic copies display concerted evolution and a species-specific pattern, whereas euchromatic repeats display a more typical evolutionary pattern, suggesting that chromatin domains may influence the evolution of these sequences. Overall, our data indicate the 1.688 satDNA as the most perduring satDNA family described in Drosophila phylogeny to date. Our study provides a strong foundation for future work on the functional roles of 1.688 satDNA across many Drosophila species.

Higher visual cognition: search, neglect, attention, and eye movements

2012 ◽  
Author(s):  
Jacinta OʼShea ◽  
Matthew F. S. Rushworth
Keyword(s):  
Eye Movements ◽  
Posterior Parietal Cortex ◽  
Visual Cognition ◽  
Spatial Neglect ◽  
Neural Basis ◽  
Functional Roles ◽  
Frontoparietal Network ◽  
Posterior Parietal ◽  
Future Work ◽  
Patient Studies

This article reviews the contribution of transcranial magnetic stimulation (TMS) research to the understanding of attention, eye movements, visual search, and neglect. It considers how TMS studies have confirmed, refined, or challenged prevailing ideas about the neural basis of higher visual cognition. It shows that TMS has enhanced the understanding of the location, timing, and functional roles of visual cognitive processes in the human brain. The main focus is on studies of posterior parietal cortex (PPC), with reference to recent work on the frontal eye fields (FEFs). TMS offers many advantages to complement neuropsychological patient studies to enhance the understanding of how the fronto-parietal cortical nerves function. The visuo-spatial neglect- and extinction-like deficits incurred by parietal damage have been modelled successfully using TMS. Future work might be directed at teasing apart the distinct functional roles of nodes within this frontoparietal network in different sensorimotor contexts.

scholarly journals Excavation and aggregation as organizing factors in de novo construction by mound-building termites

2017 ◽  
Vol 284 (1856) ◽  
pp. 20162730 ◽  
Author(s):  
Ben Green ◽  
Paul Bardunias ◽  
J. Scott Turner ◽  
Radhika Nagpal ◽  
Justin Werfel
Keyword(s):  
Feedback Loop ◽  
De Novo ◽  
Early Stage ◽  
Agent Based ◽  
Functional Roles ◽  
Mound Construction ◽  
Aggregation Activity ◽  
Future Work ◽  
Excavation Site ◽  
Traditional Understanding

Termites construct complex mounds that are orders of magnitude larger than any individual and fulfil a variety of functional roles. Yet the processes through which these mounds are built, and by which the insects organize their efforts, remain poorly understood. The traditional understanding focuses on stigmergy, a form of indirect communication in which actions that change the environment provide cues that influence future work. Termite construction has long been thought to be organized via a putative ‘cement pheromone’: a chemical added to deposited soil that stimulates further deposition in the same area, thus creating a positive feedback loop whereby coherent structures are built up. To investigate the detailed mechanisms and behaviours through which termites self-organize the early stages of mound construction, we tracked the motion and behaviour of major workers from two Macrotermes species in experimental arenas. Rather than a construction process focused on accumulation of depositions, as models based on cement pheromone would suggest, our results indicated that the primary organizing mechanisms were based on excavation. Digging activity was focused on a small number of excavation sites, which in turn provided templates for soil deposition. This behaviour was mediated by a mechanism of aggregation, with termites being more likely to join in the work at an excavation site as the number of termites presently working at that site increased. Statistical analyses showed that this aggregation mechanism was a response to active digging, distinct from and unrelated to putative chemical cues that stimulate deposition. Agent-based simulations quantitatively supported the interpretation that the early stage of de novo construction is primarily organized by excavation and aggregation activity rather than by stigmergic deposition.

Corrigendum to: Filling gaps in the biology and habitat use of two spurdog sharks (Squalus japonicus and Squalus brevirostris) in the East China Sea

2020 ◽  
Vol 71 (12) ◽  
pp. 1732
Author(s):  
Toshikazu Yano ◽  
Seiji Ohshimo ◽  
Takeshi Sakai ◽  
Mari Yoda
Keyword(s):  
East China Sea ◽  
Additive Model ◽  
Habitat Characteristics ◽  
East China ◽  
Shark Species ◽  
The East China Sea ◽  
Generalised Additive Model ◽  
China Sea ◽  
Important Prey ◽  
Conservation And Management

The conservation and management of sharks requires appropriate information on their biological and habitat characteristics. Data needed for the conservation and management of two dominant demersal shark species in the East China Sea, the spurdogs (Squalus japonicus and Squalus brevirostris), are inadequate. To remedy this, we analysed biological, catch and abiotic data from bottom trawl surveys conducted in 2000–05 and 2008–14 from within the East China Sea. The precaudal length of male and female S. japonicus at 50% sexual maturity was 396.1 and 459.9mm respectively, whereas for S. brevirostris it was 289.6 and 354.9mm respectively. Prey overlap was high between species, with lanternfishes the most important prey. The fractional trophic level was 4.33 for S. japonicus and 4.31 for S. brevirostris. We estimated spurdog habitat using a generalised additive model. Depth affected the presence of both sharks, with latitude also affecting the presence of S. brevirostris. These two spurdog species were spatially segregated over the continental slope, and body-length and sex-ratio distributions suggested that there was a maturity-based segregation within and among species. The results of this study improve our understanding of the population dynamics of these spurdog species, their reproduction and diet, fundamental information required for their conservation and for improved fisheries management.

scholarly journals Shark Conservation – Analysis and Synthesis

2021 ◽  
Author(s):  
Ila France Porcher ◽  
Brian W Darvell ◽  
Iris Ziegler
Keyword(s):  
Teleost Fish ◽  
Iucn Red List ◽  
Commercial Fishing ◽  
Shark Species ◽  
Ecological Value ◽  
Fish Stocks ◽  
Global Demand ◽  
Analysis And Synthesis ◽  
The Will ◽  
Species Being

A detailed analysis of fishing records has shown that the shark species accessible to global fisheries have been systematically depleted for decades. They were already fished to about 10 percent of their former levels by 2003. Now one species after another is being listed on the IUCN Red List of Threatened Species as their numbers drop towards extinction. Shark depletion has not been well documented and a large proportion of shark mortality has been bycatch, the target species being teleost fish. But with the rise in value of shark fins due to the shark fin trade, at the same time as teleost fish stocks have become severely overfished, sharks, along with tuna, have become the most valuable catches. Fishing on the high seas is scarcely profitable, and so is heavily supported by subsidies. But the shark fin trade, in which organized crime is heavily involved, is driven by enormous profits and provides a powerful demand for the fins of all sharks. Thus it is now being supplied by fisheries around the world. There is no interest in sustainability in consumer countries, and neither the will nor the resources to manage the trade exist. Although some shark fisheries might have been managed sustainably in some regions for certain species for meat, such fisheries are increasingly dependent on the shark fin trade.. The rising global demand for shark fins, coupled with the increasing depletion of the animals supplying that demand, makes commercial fishing for sharks unsustainable. Given their high ecological value across the aquatic ecosystems they inhabit, it is important that they receive more effective measures of protection going far beyond the currently existing ones. In particular, protection of all sharks, manta rays, devil rays and rhino rays through an Appendix I CITES listing should be effected immediately due to the scale of the global take of the shark fin trade and the state of shark depletion amply documented in the literature.

scholarly journals Functional diversity of reef molluscs along a tropical-to-temperate gradient

Coral Reefs ◽  
2020 ◽  
Vol 39 (5) ◽  
pp. 1361-1376
Author(s):  
Matthew Floyd ◽  
Masaru Mizuyama ◽  
Masami Obuchi ◽  
Brigitte Sommer ◽  
Mark GR Miller ◽  
...  
Keyword(s):  
Functional Diversity ◽  
Marine Species ◽  
Range Shifts ◽  
Human Populations ◽  
Ecological Communities ◽  
Functional Changes ◽  
Transition Zones ◽  
Important Prey ◽  
Functional Understanding ◽  
Mollusc Assemblages

Abstract Global warming is leading to range shifts of marine species, threatening the structure and functioning of ecological communities and human populations that rely on them. The largest changes are seen in biogeographic transition zones, such as subtropical reef communities, where species range shifts are already causing substantial community reorganisation. This causes functional changes in communities over subtropical latitudes, though a baseline functional understanding remains elusive for many taxa. One key marine taxon are molluscs, which provide many ecosystem services, are important prey for fishes and are also fisheries targets themselves, but remain largely unstudied. Here, we examine the trait composition, functional diversity, and functional redundancy of mollusc assemblages along the tropical-to-temperate transition in Japan (25° to 35° Northern latitude). Specifically, we use a trait database of 88 mollusc species from 31 subtropical reefs along the Pacific coast of Japan to show that trait composition of mollusc assemblages changes continuously along the latitudinal gradient. We discover that functional diversity of mollusc assemblages decreases with increasing latitude, a pattern associated with declines in functional dispersion. Moreover, we find a clear distinction between tropical and subtropical mollusc assemblages, with substrate-attached, suspension feeding bivalves more abundant in the tropics and free-living gastropod grazers more prevalent at higher latitudes. Our trait-based evidence in this study shows a contraction and almost complete shift in the functioning of marine mollusc assemblages at biogeographic transition zones and our trait database facilitates further study. Our findings provide evidence of the changing taxonomic and functional composition of extant mollusc communities with latitude, pointing to potential pertinent changes and tropicalisation of these communities with rapid ocean warming.

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