Genetics in conservation and wildlife management: a revolution since Caughley

2009 ◽  
Vol 36 (1) ◽  
pp. 70 ◽  
Author(s):  
Stephen D. Sarre ◽  
Arthur Georges

In his 1994 review of conservation biology, Graeme Caughley questioned the central role for genetics in that discipline. His central theme was that there was no known case of genetic malfunction leading to the extinction of a population or species, and that driving forces such as overkill, habitat fragmentation and introduced predators as well as environmental and demographic stochasticity of small populations should be considered ahead of genetics in the debate about extinction prevention. At the time, only indirect and theoretical evidence existed for genetic contributions to the declines of wildlife and most of the debate revolved around the impact of genetic variation on fitness and long-term persistence. In addition, the application of DNA technologies to the study of wildlife was in its infancy. Though this was not Caughley’s intention, many within wildlife management took his criticisms of genetic aspects of species decline as the cue to dismiss this branch of science as of minor relevance to conservation biology. Since Caughley’s critique, there has been a revolution in genetic technologies for non-model organisms with the arrival of highly informative hypervariable DNA markers. Perhaps even more importantly, developments in DNA and gene technologies have provided the opportunity to study fundamental life-history traits such as disease resistance in more direct ways than previously possible. In concert with these tools, conservation geneticists have risen to Caughley’s challenge and demonstrated unambiguously a clear role for genetic analysis in conservation biology. Despite these impressive advances, there remains an important gap between the genetic approaches available and their uptake by managers. Bridging this gap will greatly increase the capacity of wildlife managers to generate the data necessary for sound management.


2019 ◽  
Vol 374 (1781) ◽  
pp. 20190013 ◽  
Author(s):  
Bernt-Erik Sæther ◽  
Steinar Engen

One of the most important challenges in conservation biology is to predict the viability of populations of vulnerable and threatened species. This requires that the demographic stochasticity strongly affecting the ecological and evolutionary dynamics of especially small populations is correctly estimated and modelled. Here, we summarize theoretical evidence showing that the demographic variance in population dynamics is a key parameter determining the probability of extinction and also is directly linked to the magnitude of the genetic drift in the population. The demographic variance is dependent on the mating system, being larger in a polygynous than in monogamous populations. Understanding factors affecting intersexual differences in mating success is therefore essential in explaining variation in the demographic variance. We hypothesize that the strength of sexual selection, for example, quantified by the Bateman gradient, may be a useful predictor of the magnitude of the demographic stochasticity and hence the genetic drift in the population. We provide results from a field study of moose that support this claim. Thus, including central principles from behavioural ecology may increase the reliability of population viability analyses through an improvement of our understanding of factors affecting stochastic influences on population dynamics and evolutionary processes. This article is part of the theme issue ‘Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation’.



2019 ◽  
Vol 25 (29) ◽  
pp. 3098-3111 ◽  
Author(s):  
Luca Liberale ◽  
Giovanni G. Camici

Background: The ongoing demographical shift is leading to an unprecedented aging of the population. As a consequence, the prevalence of age-related diseases, such as atherosclerosis and its thrombotic complications is set to increase in the near future. Endothelial dysfunction and vascular stiffening characterize arterial aging and set the stage for the development of cardiovascular diseases. Atherosclerotic plaques evolve over time, the extent to which these changes might affect their stability and predispose to sudden complications remains to be determined. Recent advances in imaging technology will allow for longitudinal prospective studies following the progression of plaque burden aimed at better characterizing changes over time associated with plaque stability or rupture. Oxidative stress and inflammation, firmly established driving forces of age-related CV dysfunction, also play an important role in atherosclerotic plaque destabilization and rupture. Several genes involved in lifespan determination are known regulator of redox cellular balance and pre-clinical evidence underlines their pathophysiological roles in age-related cardiovascular dysfunction and atherosclerosis. Objective: The aim of this narrative review is to examine the impact of aging on arterial function and atherosclerotic plaque development. Furthermore, we report how molecular mechanisms of vascular aging might regulate age-related plaque modifications and how this may help to identify novel therapeutic targets to attenuate the increased risk of CV disease in elderly people.



Author(s):  
Caroline Dubbert ◽  
Awudu Abdulai

Abstract Many studies show that participation in contract farming has positive impacts on farm productivity and incomes. Most of the literature, however, does not take into account that contracts vary in their specifications, making empirical evidence scarce on the diverse impacts of different types of contracts. In this study, we investigate the driving forces of participation in marketing and production contracts, relative to spot markets. We also study the extent to which different contract types add additional benefits to smallholder farmers, using recent survey data of 389 cashew farmers in Ghana. To account for selection bias arising from observed and unobserved factors, we apply a multinomial endogenous switching regression method and implement a counterfactual analysis. The empirical results demonstrate that farmers who participate in production contracts obtain significantly higher cashew yields, cashew net revenues, and are more food secure compared to spot market farmers. We also find substantial heterogeneity in the impact of marketing and production contracts across scale of operation. Small sized farms that participate in production contracts tend to benefit the most. Marketing contracts, however, do not appear to benefit cashew farmers.



2000 ◽  
Vol 118 (1) ◽  
pp. 21-29 ◽  
Author(s):  
Ulysses Fagundes-Neto ◽  
Isabel Cristina Affonso Scaletsky

Diarrheal disease is still the most prevalent and important public health problem in developing countries, despite advances in knowledge, understanding, and management that have occurred over recent years. Diarrhea is the leading cause of death in children under 5 years of age. The impact of diarrheal diseases is more severe in the earliest periods of life, when taking into account both the numbers of episodes per year and hospital admission rates. This narrative review focuses on one of the major driving forces that attack the host, namely the enteropathogenic Escherichia coli (EPEC) and the consequences that generate malnutrition in an early phase of life. EPEC serotypes form dense microcolonies on the surface of tissue-culture cells in a pattern known as localized adherence (LA). When EPEC strains adhere to epithelial cells in vitro or in vivo they cause characteristic changes known as Attaching and Effacement (A/E) lesions. Surface abnormalities of the small intestinal mucosa shown by scanning electron microscopy in infants with persistent diarrhea, although non-specific, are intense enough to justify the severity of the clinical aspects displayed in a very young phase in life. Decrease in number and height of microvilli, blunting of borders of enterocytes, loss of the glycocalyx, shortening of villi and presence of a mucus pseudomembrane coating the mucosal surface were the abnormalities observed in the majority of patients. These ultrastructural derangements may be due to an association of the enteric enteropathogenic agent that triggers the diarrheic process and the onset of food intolerance responsible for perpetuation of diarrhea. An aggressive therapeutic approach based on appropriate nutritional support, especially the utilization of human milk and/or lactose-free protein hydrolyzate-based formulas and the adequate correction of the fecal losses, is required to allow complete recovery from the damage caused by this devastating enteropathogenic agent.



1999 ◽  
Vol 26 (3) ◽  
pp. 218-228 ◽  
Author(s):  
SARAH GILLINGHAM ◽  
PHYLLIS C. LEE

In recent years there has been a proliferation of projects aiming to integrate human development needs with conservation objectives, and to establish mutually beneficial relationships for the management of natural resources between rural communities and the state. This paper presents data from a case study of human-wildlife interactions in villages along the northern boundary of the Selous Game Reserve in south-east Tanzania. Since 1989, this area has been the site of a project working to promote community wildlife management (CWM). Questionnaire survey data were used to examine villagers' conservation attitudes towards wildlife, the Game Reserve, and the activities of the CWM project and state wildlife management authority. Despite local support for the conservation of wildlife, many respondents were either unaware or held negative views of the activities of the wildlife management institutions. Logistic regression analyses show that while access to game meat from the CWM project has had a positive influence on perceptions of wildlife benefits and awareness of the project's activities, it has had no significant effect on local perceptions of the Game Reserve and the activities of the state wildlife management authority. The factors underlying the observed pattern of conservation attitudes were identified as the inequitable distribution of benefits from the CWM project, and the limited nature of community participation in wildlife management. The importance of institutional issues for the future progress of participatory approaches to conservation with development is emphasized.



2007 ◽  
Vol 4 (16) ◽  
pp. 851-863 ◽  
Author(s):  
Alun L Lloyd ◽  
Ji Zhang ◽  
A.Morgan Root

Demographic stochasticity and heterogeneity in transmission of infection can affect the dynamics of host–vector disease systems in important ways. We discuss the use of analytic techniques to assess the impact of demographic stochasticity in both well-mixed and heterogeneous settings. Disease invasion probabilities can be calculated using branching process methodology. We review the use of this theory for host–vector infections and examine its use in the face of heterogeneous transmission. Situations in which there is a marked asymmetry in transmission between host and vector are seen to be of particular interest. For endemic infections, stochasticity leads to variation in prevalence about the endemic level. If these fluctuations are large enough, disease extinction can occur via endemic fade-out. We develop moment equations that quantify the impact of stochasticity, providing insight into the likelihood of stochastic extinction. We frame our discussion in terms of the simple Ross malaria model, but discuss extensions to more realistic host–vector models.



2017 ◽  
Vol 38 (1) ◽  
pp. 22
Author(s):  
Peter D Kirkland

‘Brainless pig disease swoops on Sydney.' This was a media headline that threatened to emerge during the early stages of a disease outbreak in pigs in NSW. However, identification of the viral cause and epidemiological studies that supported a sound management program minimised the impact of this outbreak on animal and human health.



2018 ◽  
Vol 22 (3) ◽  
pp. 194-211 ◽  
Author(s):  
Yongqi Feng ◽  
Tianshu Zhang

Purpose The purpose of this paper is to provide a better understanding of the driving forces and structural changes of China as a market provider for Korea. This paper gives the answers for the following questions: How do China’s final demands trigger the growth of its imports from Korea? And what’s the impact of China’s final demands on the import in different industries? Design/methodology/approach Based on the Multi-Regional Input-Output model and World Input-Output Table database, this paper constructs the non-competitive imports input-output (IO) table of China to Korea. According to this table, we can calculate the induced imports coefficient and comprehensive induced import coefficients of China’s four final demands for imports from Korea in the 56 industries in China. Findings Among the four driving forces, the strongest one is changes in inventories and valuables. The impact of final consumption expenditure and fixed capital formation is much lower than that of changes in inventories and valuables, but they have a broader impact for the 56 industries. This paper finds out the China’s import induction of the final demands to Korea peaked in 2005 and 2010 and decreased greatly in 2014, so the position of China as market provider for Korea will no longer rise substantially, contrarily it will be in a steady state. Originality/value First, this paper constructs the non-competitive IO table to analyze the market provider issues between two countries and provides practical ways and methods for studies on the issues of imports and market provider. Second, this paper investigates the different roles of four final demands on driving force of China as market provider for Korea and the structural changes of China as a market provider for Korea among 56 industries from 2000 to 2014.



2017 ◽  
Vol 71 (2) ◽  
pp. 155-165 ◽  
Author(s):  
Aleksandar Dosic ◽  
Dragana Tomasevic-Pilipovic ◽  
Miladin Gligoric ◽  
Bozo Dalmacija ◽  
Djurdja Kerkez ◽  
...  

Increasing amounts of residues and waste materials coming from industrial activities in different processes have become an increasingly urgent problem for the future. The paper presents the problem of mine tailings generated in mine ?Sase? (Republic of Srpska, Bosnia and Herzegovina) with high metal content (Pb, Cu and Zn). Dumpsite of this tailing represents potential risk for water bodies in the vicinity of this location. Chosen treatment process was stabilization/solidification (S/S). Inorganic agents used in this study were fly ash and red mud that represent secondary industrial waste generated on locations relatively near the mine. Therefore, their application can be used as an example of a sustainable solution of regional environmental problem. Further investigations are related to the impact of various factors on metals leaching from mine tailings solidified/stabilized material using the above mentioned immobilization agents. The performance of the immobilizing procedures was examined using several leaching tests: ANS 16.1, TCLP, DIN, MWLP. The results indicated that all S/S samples can be considered as non-hazardous waste, as all leached metal concentrations met the set criteria. These results will further enable the modelling of metals behaviour during long-term leaching from treated mine tailing. The data are invaluable in terms of economically and environmentally sound management of mine tailing.



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