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1.
CASEY HUMBYRD 《Developing world bioethics》2009,9(3):111-118
Since the development of assisted reproductive technologies, infertile individuals have crossed borders to obtain treatments unavailable or unaffordable in their own country. Recent media coverage has focused on the outsourcing of surrogacy to developing countries, where the cost for surrogacy is significantly less than the equivalent cost in a more developed country. This paper discusses the ethical arguments against international surrogacy. The major opposition viewpoints can be broadly divided into arguments about welfare, commodification and exploitation.
It is argued that the only valid objection to international surrogacy is that surrogate mothers may be exploited by being given too little compensation. However, the possibility of exploitation is a weak argument for prohibition, as employment alternatives for potential surrogate mothers may be more exploitative or more harmful than surrogacy. It is concluded that international surrogacy must be regulated, and the proposed regulatory mechanism is termed Fair Trade Surrogacy. The guidelines of Fair Trade Surrogacy focus on minimizing potential harms to all parties and ensuring fair compensation for surrogate mothers. 相似文献
It is argued that the only valid objection to international surrogacy is that surrogate mothers may be exploited by being given too little compensation. However, the possibility of exploitation is a weak argument for prohibition, as employment alternatives for potential surrogate mothers may be more exploitative or more harmful than surrogacy. It is concluded that international surrogacy must be regulated, and the proposed regulatory mechanism is termed Fair Trade Surrogacy. The guidelines of Fair Trade Surrogacy focus on minimizing potential harms to all parties and ensuring fair compensation for surrogate mothers. 相似文献
2.
Enhancing autonomy in paid surrogacy 总被引:1,自引:0,他引:1
The gestational surrogate – and her economic and educational vulnerability in particular – is the focus of many of the most persistent worries about paid surrogacy. Those who employ her, and those who broker and organize her services, usually have an advantage over her in resources and information. That asymmetry exposes her to the possibility of exploitation and abuse. Accordingly, some argue for banning paid surrogacy. Others defend legal permission on grounds of surrogate autonomy, but often retain concerns about the surrogate. In response to the dilemma of a ban versus bald permission, we propose a 'soft law' approach: states should require several hours of education of surrogates – education aimed at informing and enhancing surrogate autonomy. 相似文献
3.
Wilkinson S 《Bioethics》2003,17(2):169-187
This paper discusses the exploitation argument against commercial surrogacy: the claim that commercial surrogacy is morally objectionable because it is exploitative. The following questions are addressed. First, what exactly does the exploitation argument amount to? Second, is commercial surrogacy in fact exploitative? Third, if it were exploitative, would this provide a sufficient reason to prohibit (or otherwise legislatively discourage) it? The focus throughout is on the exploitation of paid surrogates, although it is noted that other parties (e.g. ‘commissioning parents’) may also be the victims of exploitation. It is argued that there are good reasons for believing that commercial surrogacy is often exploitative. However, even if we accept this, the exploitation argument for prohibiting (or otherwise legislatively discouraging) commercial surrogacy remains quite weak. One reason for this is that prohibition may well ‘backfire’ and lead to potential surrogates having to do other things that are more exploitative and/or more harmful than paid surrogacy. It is concluded therefore that those who oppose exploitation should (rather than attempting to stop particular practices like commercial surrogacy) concentrate on: (a) improving the conditions under which paid surrogates ‘work’; and (b) changing the background conditions (in particular, the unequal distribution of power and wealth) which generate exploitative relationships. 相似文献
4.
JENNIFER A. PARKS 《Bioethics》2010,24(7):333-340
This essay will focus on the moral issues relating to surrogacy in the global context, and will critique the liberal arguments that have been offered in support of it. Liberal arguments hold sway concerning reproductive arrangements made between commissioning couples from wealthy nations and the surrogates from socioeconomically weak backgrounds that they hire to do their reproductive labor. My argument in this paper is motivated by a concern for controlling harms by putting the practice of globalized commercial surrogacy into the context of care ethics. As I will argue, the unstable situations into which children of global surrogacy arrangements are born is symbolic of the crisis of care that the practice raises. Using the Baby Manji case as my touch point, I will suggest that liberalism cannot address the harms experienced by Manji and children like her who are created through the global practice of assisted reproductive technology. I will argue that, if commissioning couples consider their proposed surrogacy contracts from a care ethics point of view, they will begin to think relationally about their actions, considering the practice from an ethical lens, not just an economic or contractual one. 相似文献
5.
Ruaim A. Muaygil 《Developing world bioethics》2017,17(2):112-120
Advances in reproductive medicine have provided new, and much needed, hope for millions of people struggling with infertility. Gestational surrogacy is one such development that has been gaining popularity with infertile couples, especially those unable to benefit from other reproductive procedures such as In Vitro Fertilization. For many Muslim couples, however, surrogacy remains a nonviable option. Islamic scholars have deemed the procedure incompatible with Islam and have prohibited its use. This paper examines the arguments presented for proscribing surrogacy arrangements in Sunni Islam in particular. These include preservation of lineage, exclusion of third parties in reproduction, upholding the rights of the child, and protection from the negative effects of surrogacy arrangements. The rationales for banning surrogacy are subsequently refuted utilizing Islamic law “Sharia”, bioethics, and medical evidence. The paper also presents reasons for why surrogacy is not only consistent with Sunni Islamic teachings, but is also both ethically justified and medically necessary. Lastly, Islamic scholars are urged to take into account the arguments presented in this paper and reconsider their rulings on the permissibility of surrogacy. 相似文献
6.
Biodiversity surrogates are often used in ecology to save money and time. One such widely used surrogacy method is the higher taxon approach, also known in the literature as taxonomic sufficiency. This approach has rarely been applied to microscopic organisms like soil microfauna, although there is a lack of detailed taxonomic knowledge regarding the latter. We tested taxonomic sufficiency for genus alpha and beta diversity, as well as for community structure of soil nematodes. We also tested whether the functional classifications of nematodes into functional guilds and trophic groups can serve as efficient indicators of nematode diversity and community structure. We used data from soil nematode communities from five different microhabitats (soil, soil moss, rock moss, low tree trunk moss and high tree trunk moss) in forested and non forested areas at five different stations (differing in elevation and aspect). Our results showed that both the higher taxon approach and the functional surrogacy approach could serve as reliable indicators of alpha and beta diversity. Furthermore, our community analysis of both taxonomic and functional composition identified that the variability at the finer scales, and namely the habitat structure, played the leading role in shaping nematode communities. 相似文献
7.
JASON K.M. HANNA 《Bioethics》2010,24(7):341-347
Many critics of commercial surrogate motherhood argue that it violates the rights of children. In this paper, I respond to several versions of this objection. The most common version claims that surrogacy involves child‐selling. I argue that while proponents of surrogacy have generally failed to provide an adequate response to this objection, it can be overcome. After showing that the two most prominent arguments for the child‐selling objection fail, I explain how the commissioning couple can acquire parental rights by paying the surrogate only for her reproductive labor. My explanation appeals to the idea that parental rights are acquired by those who have claims over the reproductive labor that produces the child, not necessarily by those who actually perform the labor. This account clarifies how commercial surrogacy differs from commercial adoption. In the final section of the paper, I consider and reject three further child‐based objections to commercial surrogacy: that it establishes a market in children's attributes, that it requires courts to stray from the best interests standard in determining custodial rights, and that it requires the surrogate to neglect her parental responsibilities. Since each of these objections fails, children's rights probably do not pose an obstacle to the acceptability of commercial surrogacy arrangements. 相似文献
8.
Yoshie Yanagihara 《Bioethics》2020,34(6):570-577
This paper aims to evoke an alternative viewpoint on surrogacy, moving beyond popular Western feminist beliefs on the practice, by introducing the history and current context of East Asian surrogacy. To elaborate a different cultural perspective on surrogacy, this paper first introduces the East Asian history of contract pregnancy systems, prior to the emergence of the American invention of ‘modern’ surrogacy practice. Then, it examines Japanese mass media portrayals of cross-border surrogacy in which white women have become ‘convenient’ entities. The results of the analysis show how Japanese culture has adopted a rhetoric about the use of white women as convenient surrogate mothers in the global commercial surrogacy market. An essential aspect of surrogacy is the premise that a woman’s reproductive function should be accessible to others. Past discussions among feminists have neglected this important point. Moreover, they share the assumption that white surrogacy clients are exploiters, who take advantage of women of colour as surrogate mothers. The current situation in Asia flips this perspective—with white women regarded as easier targets for exploitation by wealthy people of colour. For Asian clients, Westerners can be easily regarded as ‘others’ whom they can use for their reproductive needs. In today's globalized era, the surrogacy industry is no longer for affluent Westerners only. Considering this change, it is crucial to discuss surrogacy issues by reconstructing feminist perspectives with a globalized view, to help protect women’s bodies, regardless of nationality, ethnicity, skin colour, or religion. 相似文献
9.
A diagnosis of fetal abnormality presents parents with a difficult – even tragic – moral dilemma. Where this diagnosis is made in the context of surrogate motherhood there is an added difficulty, namely that it is not obvious who should be involved in making decisions about abortion, for the person who would normally have the right to decide – the pregnant woman – does not intend to raise the child. This raises the question: To what extent, if at all, should the intended parents be involved in decision‐making? In commercial surrogacy it is thought that as part of the contractual agreement the intended parents acquire the right to make this decision. By contrast, in altruistic surrogacy the pregnant woman retains the right to make these decisions, but the intended parents are free to decide not to adopt the child. We argue that both these strategies are morally unsound, and that the problems encountered serve to highlight more fundamental defects within the commercial and altruistic models, as well as in the legal and institutional frameworks that support them. We argue in favour of the professional model, which acknowledges the rights and responsibilities of both parties and provides a legal and institutional framework that supports good decision‐making. In particular, the professional model acknowledges the surrogate's right to decide whether to undergo an abortion, and the intended parents' obligation to accept legal custody of the child. While not solving all the problems that arise in surrogacy, the model provides a framework that supports good decision‐making. 相似文献
10.
Kalindi Vora 《Ethnos》2014,79(1):63-83
AbstractThis article marks experimental modes of sociality in a transnational Indian assisted reproductive technology (ART) clinic as a contact zone between elite doctors, gestational surrogates, and transnational commissioning parents. It examines efforts within one ART clinic to separate social relationships from reproductive bodies in its surrogacy arrangements as well as novel social formations occurring both because of and despite these efforts. Draft regulative legislation in India marks a shift in the distribution of risk among actors in the clinic that parallels a shift in medical practice away from a technique of caring for the body to producing bodies as instruments of contracted service. The clinic provides an opportunity to observe forms of sociality that emerge as experiments with modernities, with different relationships to the body and the social meaning of medicalized biological reproduction, and with understanding the role of the market and altruism in the practice of gestational surrogacy. 相似文献
11.
The majority of biodiversity assessments use species as the base unit. Recently, a series of studies have suggested replacing numbers of species with higher ranked taxa (genera, families, etc.); a method known as taxonomic surrogacy that has an important potential to save time and resources in assesments of biological diversity. We examine the relationships between taxa and ranks, and suggest that species/higher taxon exchanges are founded on misconceptions about the properties of Linnaean classification. Rank allocations in current classifications constitute a heterogeneous mixture of various historical and contemporary views. Even if all taxa were monophyletic, those referred to the same rank would simply denote separate clades without further equivalence. We conclude that they are no more comparable than any other, non‐nested taxa, such as, for example, the genus Rattus and the phylum Arthropoda, and that taxonomic surrogacy lacks justification. These problems are also illustrated with data of polychaetous annelid worms from a broad‐scale study of benthic biodiversity and species distributions in the Irish Sea. A recent consensus phylogeny for polychaetes is used to provide three different family‐level classifications of polychaetes. We use families as a surrogate for species, and present Shannon‐Wiener diversity indices for the different sites and the three different classifications, showing how the diversity measures rely on subjective rank allocations. 相似文献
12.
Surrogacy analysis consists of determining a set of biotic or environmental parameters which can be rapidly assessed in the
field and reliably used to prioritize places for biodiversity conservation. Whether adequate surrogate sets exist remains
an open and relatively unexplored question though its solution is central to the aims of conservation biology. This paper
analyses the surrogacy problem by prioritizing places using surrogate lists and comparing these results with those obtained
by using more comprehensive species lists. More specifically, it explores (i) the possibility of using bird distributions,
which are often easily available, as surrogates for species at risk (endangered and threatened species), which are presumed
to be an important component of biodiversity; and (ii) the methodological question of how spatial scale influences surrogate
success. The data set analysed, from southern Québec, is one of the most complete biotic data sets available at the regional
scale. Contrary to some previous analyses, the results obtained suggest that the surrogacy problem is potentially solvable. 相似文献
13.
Sheng Lin Min‐Sheng You Liette Vasseur Guang Yang Feng‐Jing Liu Feng Guo 《Insect Science》2012,19(3):419-425
Abstract Biodiversity assessments can often be time‐ and resource‐consuming. Several alternative approaches have been proposed to reduce sampling efforts, including indicator taxa and surrogates. In this study, we examine the reliability of higher taxon surrogates to predict species richness in two experimental rice fields of Fujian Province, southeastern China during 2005 and 2009. Spider samples in transgenic and nontransgenic plots were collected using a suction sampler. Both the genus and family surrogates had significant and positive linear relationships with species richness in the transgenic and nontransgenic rice fields. The rice varieties did not significantly influence the linear relationships. Our findings suggest that higher‐taxon surrogacy could be a useful alternative to complete species inventory for risk assessments of transgenic rice. 相似文献
14.
Benthic invertebrates are good indicators of aquatic ecosystem health. Yet, environmental monitoring and assessment of community changes in relation to both natural and human sources of disturbance involves considerable efforts for sample processing and time-consuming identifications of organisms, which make challenging large-scale and continuous monitoring programs required under the current regulatory frameworks at European scale. The use of higher taxa (e.g. families) as surrogates for species is a mainstream approach to reduce cost and time associated to fine taxonomic resolution in environmental studies, especially concerning macro-invertebrate communities. However, this approach of ‘taxonomic sufficiency’ simply relies on the static grouping of organisms in taxa belonging to a single higher taxonomic level irrespective of their ecological relevance or difficulties in their taxonomic identification, leading to unnecessary losses of taxonomic detail or ecological information. A new approach, namely the Best Practicable Aggregation of Species (BestAgg), has been recently developed as an alternative procedure for species surrogacy. BestAgg is based on aggregating species in the minimum number of surrogates sufficient to depict species-level community patterns consistently, while capitalizing on ecological information. Although the approach has been successfully applied to marine and freshwater invertebrate assemblages, its effectiveness in transitional water systems, where the complex and highly variable environmental conditions may affect the performance of surrogacy methods, still remain untested. Here, we applied the BestAgg approach to quantifying spatio-temporal patterns of variability of macro-invertebrate assemblages from Mediterranean coastal lagoons (Northern Adriatic Sea). Surrogates were defined using species-level data from a representative lagoon system, which served as pilot study. Then, they were used to analyze macro-invertebrate assemblages in two independent lagoons in the same geographic area. Results showed that BestAgg surrogates were effective in depicting multivariate patterns of macro-invertebrate assemblages as at species level over and beyond potential variations among the investigated lagoons. The use of families, following a more classic approach based on taxonomic sufficiency, also provided results comparable to those obtained using species. However, with respect to families, BestAgg surrogates allowed an estimated timesaving of 40% higher while still retaining an equivalent amount of information on species-level patterns. More importantly, BestAgg allowed exploiting different criteria of species aggregation, leading to a set of surrogates more aligned with ecological/functional characteristics of organisms, suggesting that BestAgg approach may provide a fresh perspective for optimizing trade-offs between pragmatism and the need for relevant ecological information in environmental assessment and monitoring. 相似文献
15.
Background
In order to improve the health of the most vulnerable groups in society, the WHO called for research on the multiple and inter-linking factors shaping the social determinants of health (SDH). This paper analyses four key SDH (social cohesion, social inclusion, social empowerment and socioeconomic security) across six Asia-Pacific countries: Australia, Hong Kong, Japan, South Korea, Taiwan, and Thailand.Methods
Population surveys were undertaken using a validated instrument in 2009-10, with sample sizes around 1000 in each country. The four SDH were analysed using multivariate binomial logistic regression to identify socio-demographic predictors in each country.Results
Low socio-economic security was associated with low income in all six study countries and with poor subjective health in Japan, South Korea and Thailand and with being married or cohabiting in Australia and Hong Kong. Low social cohesion was associated with low income in all countries and with undertaking household duties in South Korea, Thailand and Taiwan. Low social inclusion was associated with low income in Australia, South Korea and Taiwan and with poor subjective health in Australia, Japan and South Korea. Older people had lower social inclusion in Taiwan (50-59 years) and Hong Kong (retired), younger people in Japan and South Korea (20-29 years in both countries) and younger and middle-aged people in Australia. Low social empowerment was associated with low income in Australia, Thailand and Taiwan, with being aged 60 years or over in Australia, Hong Kong and South Korea, and over 50 years in Thailand.Conclusions
This paper provides baseline measures for identifying where and how policy should be altered to improve the SDH. Furthermore, these data can be used for future policy evaluation to identify whether changes in policy have indeed improved the SDH, particularly for marginalised and vulnerable populations. 相似文献16.
In a context of scarce financial and human resources, the allocation of conservation efforts needs to be optimized. Our analysis attempts to draw conclusions on the integration of regional and local conservation assessments, specifically, with regard to the acquisition of fine‐scale data to complement the regional assessment. This study undertaken in Réunion Island (Indian Ocean) assessed how biodiversity surrogates targeted at a regional scale represented other biodiversity surrogates at a local scale. Biodiversity surrogates at both scales consisted of species, habitats and processes. Habitats and processes at regional scale were defined using a coarser scale of thematic resolution than at local scale. The surrogacy was tested in terms of incidental representation of local‐scale features in the regional assessments, and correlation of irreplaceability values between scales. Near‐minimum sets and irreplaceability values were generated using MARXAN software. Our results revealed that conservation targets for processes at local scale were never met incidentally, while threatened species and fragmented habitats were also usually under‐represented. More specifically, requiring only 12% of the local planning domain, the application of species as surrogates at regional scale was the least effective option at representing biodiversity features at local scale. In contrast, habitats at a coarse scale of thematic resolution achieved a significant proportion of conservation targets incidentally (67%) and their irreplaceability values were well correlated with the irreplaceability values of surrogates at local scale. The results highlighted that all three types of biodiversity surrogates are complementary for assessing overall biodiversity. Because of the cost of data acquisition, we recommended that the most efficient strategy to develop nested regional/local conservation plans is to apply habitats and processes at a coarse scale of thematic resolution at regional scale, and threatened species and degraded habitats at local scale, with their fine‐scale mapping limited to highly transformed areas. 相似文献
17.
The ED strategy: how species-level surrogates indicate general biodiversity patterns through an 'environmental diversity' perspective 总被引:5,自引:1,他引:4
Biodiversity assessment requires that we use surrogate information in practice to indicate more general biodiversity patterns. ‘ED’ refers to a surrogates framework that can link species data and environmental information based on a robust relationship of compositional dissimilarities to ordinations that indicate underlying environmental variation. In an example analysis of species and environmental data from Panama, the environmental and spatial variables that correlate with an hybrid multi‐dimensional scaling ordination were able to explain 83% of the variation in the corresponding Bray Curtis dissimilarities. The assumptions of ED also provide the rationale for its use of p‐median optimization criteria to measure biodiversity patterns among sites in a region. M.B. Araújo, P.J. Densham & P.H. Williams (2004, Journal of Biogeography 31 , 1) have re‐named ED as ‘AD’ in their evaluation of the surrogacy value of ED based on European species data. Because lessons from previous work on ED options consequently may have been neglected, we use a corroboration framework to investigate the evidence and ‘background knowledge’ presented in their evaluations of ED. Investigations focus on the possibility that their weak corroboration of ED surrogacy (non‐significance of target species recovery relative to a null model) may be a consequence of Araújo et al.'s use of particular evidence and randomizations. We illustrate how their use of discrete ED, and not the recommended continuous ED, may have produced unnecessarily poor species recovery values. Further, possible poor optimization of their MDS ordinations, due to small numbers of simulations and/or low resolution of stress values appears to have provided a possible poor basis for ED application and, consequently, may have unnecessarily favoured non‐corroboration results. Consideration of Araújo et al.'s randomizations suggests that acknowledged sampling biases in the European data have not only artefactually promoted the non‐significance of ED recovery values, but also artefactually elevated the significance of competing species surrogates recovery values. We conclude that little credence should be given to the comparisons of ED and species‐based complementarity sets presented in M.B. Araújo, P.J. Densham & P.H. Williams (2004, Journal of Biogeography 31 , 1), unless the factors outlined here can be analysed for their effects on results. We discuss the lessons concerning surrogates evaluation emerging from our investigations, calling for better provision in such studies of the background information that can allow (i) critical examination of evidence (both at the initial corroboration and re‐evaluation stages), and (ii) greater synthesis of lessons about the pitfalls of different forms of evidence in different contexts. 相似文献
18.
Ayesha I. T. Tulloch Iadine Chadès Yann Dujardin Martin J. Westgate Peter W. Lane David Lindenmayer 《Ecography》2016,39(12):1185-1196
In conservation it is inevitable that surrogates be selected to represent the occurrence of hard‐to‐find species and find priority locations for management. However, species co‐occurrence can vary over time. Here we demonstrate how temporal dynamics in species co‐occurrence influence the ability of managers to choose the best surrogate species. We develop an efficient optimisation formulation that selects the optimal set of complementary surrogate species from any co‐occurrence network. We apply it to two Australian datasets on successional bird responses to disturbances of revegetation and fire. We discover that a surprisingly small number of species are required to represent the majority of species co‐occurrences at any one time. Because co‐occurrence patterns are temporally dynamic, the optimal set of surrogates, and the number of surrogates required to achieve a desired surrogacy power, depend on sampling effort and the successional state of a system. Overlap in optimal sets of surrogates for representing 70% of co‐occurring species ranges from zero to 57% depending on when the surrogacy decision is made. Surrogate sets representing early successional communities over‐estimate the power of surrogacy decisions at later times. Our results show that in dynamic systems, optimal surrogates might be selected in different ways: 1) use short‐term monitoring to choose a larger number of static less‐informative surrogates; 2) use long‐term monitoring to choose a smaller number of static high‐power surrogates that may poorly represent early successional co‐occurrence; 3) develop adaptive surrogate selection frameworks with high short‐term and long‐term surrogacy power that update surrogate sets and capture temporal dynamics in species co‐occurrence. Our results suggest vigilance is needed when selecting surrogates for other co‐occurring species in dynamic landscapes, as selected surrogates from one time may have reduced effectiveness at a different time. Ultimately, decisions that fail to acknowledge dynamic species co‐occurrence will lead to uninformative or redundant surrogates. 相似文献
19.
In European forests, large scale biodiversity monitoring networks need to be implemented – networks which include components such as taxonomical groups that are at risk and that depend directly on forest stand structure. In this context, monitoring the species-rich group of saproxylic beetles is challenging. In the absence of sufficient resources to comprehensively survey a particular group, surrogates of species richness can be meaningful tools in biodiversity evaluations. In search of restricted subsets of species to use as surrogates of saproxylic beetle richness, we led a case study in Western Europe.Beetle data were compiled from 67 biodiversity surveys and ecological studies carried out from 1999 to 2010 with standardised trapping methods in France and Belgium. This large-scale dataset contains 642 forest plots, 1521 traps and 856 species. Twenty-two simplified species subsets were identified as potential surrogates, as well as the number of genera, a higher taxonomic level, taking into account, for each surrogate, the effort required for species identification, the practical monitoring experience necessary, the species conservation potential or the frequency of species occurrence. The performance of each surrogate was analyzed based on the following parameters: overall surrogacy (correlation between subset richness and total species richness), surrogacy vs. identification cost balance, surrogacy variation over a wide range of ecological conditions (forest type, altitude, latitude and bio-geographical area) and consistency with spatial scale. Ecological representativeness and ability to monitor rare species were supplementary criteria used to assess surrogate performance.The subsets consisting of the identifiable (or only easy-to-identify species) could easily be applied in practice and appear to be the best performing subsets, from a global point of view.The number of genera showed good prediction at the trap level and its surrogacy did not vary across wide environmental gradients. However, the subset of easy-to-identify species and the genus number were highly sensitive to spatial scale, which limits their use in large-scale studies. The number of rare species or the species richness of single beetle families (even the best single-family subset, the Cerambycidae) was very weak surrogates for total species richness. Conversely, the German list of monitoring species had high surrogacy, low identification costs and was not strongly influenced by the main geographical parameters, even with our French and Belgian data.In European-wide monitoring networks, such internationally validated subsets could be very useful with regard to the timing and cost-efficiency of field inventories. 相似文献
20.
Mellin C Delean S Caley J Edgar G Meekan M Pitcher R Przeslawski R Williams A Bradshaw C 《PloS one》2011,6(6):e20141
The use of biological surrogates as proxies for biodiversity patterns is gaining popularity, particularly in marine systems where field surveys can be expensive and species richness high. Yet, uncertainty regarding their applicability remains because of inconsistency of definitions, a lack of standard methods for estimating effectiveness, and variable spatial scales considered. We present a Bayesian meta-analysis of the effectiveness of biological surrogates in marine ecosystems. Surrogate effectiveness was defined both as the proportion of surrogacy tests where predictions based on surrogates were better than random (i.e., low probability of making a Type I error; P) and as the predictability of targets using surrogates (R(2)). A total of 264 published surrogacy tests combined with prior probabilities elicited from eight international experts demonstrated that the habitat, spatial scale, type of surrogate and statistical method used all influenced surrogate effectiveness, at least according to either P or R(2). The type of surrogate used (higher-taxa, cross-taxa or subset taxa) was the best predictor of P, with the higher-taxa surrogates outperforming all others. The marine habitat was the best predictor of R(2), with particularly low predictability in tropical reefs. Surrogate effectiveness was greatest for higher-taxa surrogates at a <10-km spatial scale, in low-complexity marine habitats such as soft bottoms, and using multivariate-based methods. Comparisons with terrestrial studies in terms of the methods used to study surrogates revealed that marine applications still ignore some problems with several widely used statistical approaches to surrogacy. Our study provides a benchmark for the reliable use of biological surrogates in marine ecosystems, and highlights directions for future development of biological surrogates in predicting biodiversity. 相似文献