Languages Are Still a Major Barrier to Global
*, Juan P. Gonza
, William J. Sutherland
1Conservation Science Group, Department of Zoology, University of Cambridge, Cambridge, United
Kingdom, 2Centre for the Study of Existential Risk, University of Cambridge, Cambridge, United Kingdom
While it is recognized that language can pose a barrier to the transfer of scientific knowl-
edge, the convergence on English as the global language of science may suggest that this
problem has been resolved. However, our survey searching Google Scholar in 16 lan-
guages revealed that 35.6% of 75,513 scientific documents on biodiversity conservation
published in 2014 were not in English. Ignoring such non-English knowledge can cause
biases in our understanding of study systems. Furthermore, as publication in English
has become prevalent, scientific knowledge is often unavailable in local languages. This hin-
ders its use by field practitioners and policy makers for local environmental issues; 54% of
protected area directors in Spain identified languages as a barrier. We urge scientific com-
munities to make a more concerted effort to tackle this problem and propose potential
approaches both for compiling non-English scientific knowledge effectively and for enhanc-
ing the multilingualization of new and existing knowledge available only in English for the
users of such knowledge.
English is obviously the language that currently dominates global scientific activities as a lingua
franca . Locally, however, many scientists and users of scientific information, such as policy
makers, communicate on a daily basis in languages other than English, which inevitably cre-
ates barriers to the transfer of knowledge between communities [2,3]. However, the magni-
tude of this problem is not well quantified, and the consequences and solutions deserve further
exploration. Language barriers may be a particularly serious problem in subjects in which local
knowledge is especially important, such as environmental sciences required for biodiversity
conservation . Languages can seriously limit the transfer of knowledge in environmental
sciences in two directions: when compiling scientific knowledge—for example, in global
assessments, such as those by the Intergovernmental Platform on Biodiversity and Ecosystem
Services (IPBES)—and when applying knowledge to local environmental issues, often tackled
by field practitioners and local policy makers. Focusing on environmental sciences as an exam-
ple, we here investigate the potential extent and consequences of language barriers in the two
directions and propose solutions for reducing this potentially overlooked problem.
PLOS Biology | DOI:10.1371/journal.pbio.2000933 December 29, 2016 1 / 8
Citation: Amano T, Gonza
´lez-Varo JP, Sutherland
WJ (2016) Languages Are Still a Major Barrier to
Global Science. PLoS Biol 14(12): e2000933.
Published: December 29, 2016
Copyright: ©2016 Amano et al. This is an open
access article distributed under the terms of the
Creative Commons Attribution License, which
permits unrestricted use, distribution, and
reproduction in any medium, provided the original
author and source are credited.
Funding: European Commission’s Marie Curie
International Incoming Fellowship Programme
(grant number PIIF-GA-2011-303221). Received
by TA. The funder had no role in study design, data
collection and analysis, decision to publish, or
preparation of the manuscript. European
Commission’s Marie Sklodowska-Curie Actions
(grant number H2020-MSCA-IF-2014- 656572).
Received by JPGV. The funder had no role in study
design, data collection and analysis, decision to
publish, or preparation of the manuscript. Isaac
Newton Trust (grant number 15.23(s)). Received
by TA and WJS. The funder had no role in study
design, data collection and analysis, decision to
publish, or preparation of the manuscript. Arcadia
Fund. Received by WJS. The funder had no role in
study design, data collection and analysis, decision
to publish, or preparation of the manuscript.
Grantham Foundation for the Protection of the
Environment. Received by TA. The funder had no
Language barriers can cause gaps in information availability during the global compilation
of scientific knowledge, as scientific information is available not only in English but also in
many other languages. We tried to estimate the number of conservation-related scientific doc-
uments published in the world’s major languages. Searching for scientific documents pub-
lished in 2014 with two keywords, “biodiversity” and “conservation”, in 16 languages on
Google Scholar generated 75,513 manuscripts, of which English was by far the most frequently
used language (48,600 scientific documents, 64.4%), followed by Spanish (9,520), Portuguese
(7,800), simplified Chinese (4,540), and French (2,290) (Fig 1). The other 11 languages sur-
veyed were used in a total of 2,763 documents (see S1 Table for more detail). By further investi-
gating 95 sample documents from those obtained using Spanish terms (the sample size was
validated by the “sample.size.prop” function in R package “samplingbook”, assuming the
expected proportion was P = 0.48 [i.e., the actual proportion of Spanish-only documents], a
finite small population correction of N = 9,520, precision e = 0.1, and confidence level = 0.95),
we confirmed that all but one document was indeed written in Spanish. Furthermore, 46 (48%
of the 95) of these documents provided neither the title nor the abstract in English (Fig 2A).
The result was similar when we investigated 80 sample documents from those obtained using
Japanese terms (the sample size was determined in the same way but with N = 474); 35% of
those documents provided neither the title nor the abstract in English (Fig 3A). Assuming sim-
ilar proportions apply to other languages, these results suggest: (1) most of the 35.6% scientific
documents written in a non-English language cannot be understood fully without the relevant
non-English language skills, and (2) up to half of the non-English scientific documents are, in
theory, unsearchable using English keywords. Moreover, having English titles and abstracts
may not suffice; of the 6 peer-reviewed papers published in Japanese by the first author of this
paper (all with an English title and 3 also with an English abstract), 4 were not searchable using
their English titles on Google Scholar, nor were two searchable on Web of Science. All 6, how-
ever, appeared on Google Scholar when searched using their Japanese titles. Google Scholar
searches can include “grey literature” (usually not peer-reviewed). However, of the 46 Spanish
documents with neither an English title nor an English abstract, over half (26) were journal
articles, books, or theses (Fig 2B) and thus are expected to have scientific credibility. Similarly,
43% (12) of the 28 Japanese documents with neither an English title nor an English abstract
were journal articles (Fig 3B). This proportion was higher in those documents with an English
title and/or an English abstract in both languages (Figs 2C and 3C). While some of these non-
English journals might not necessarily be committed to publishing papers of reasonable quality
, there are also well-established journals that regularly publish a non-negligible number of
Fig 1. Waffle plot of the number of scientific documents in 2014 alone based on a search with twokeywords—“biodiversity” and
“conservation”—in 16 major languages on Google Scholar. Each square represents 50 documents. The flags merely represent the
language of each document, not where the work originated. See S1 Table for more detail.
PLOS Biology | DOI:10.1371/journal.pbio.2000933 December 29, 2016 2 / 8
role in study design, data collection and analysis,
decision to publish, or preparation of the
Competing Interests: The authors have declared
that no competing interests exist.
Abbreviations: IPBES, Intergovernmental Platform
on Biodiversity and Ecosystem Services.
Provenance: Not commissioned; externally peer
peer-reviewed papers on biodiversity conservation in non-English languages (see examples in
S1 Table). The same is true for scientific data: global (i.e., English-based) biodiversity databases
store fewer data from countries with fewer English speakers , but this could be partly
because data from those countries are not necessarily available in English. For example, over 4
million records on species occurrence and abundance, including over 1 million based on mon-
itoring surveys organized by the Ministry of the Environment in Japan, are available online
(http://ikilog.biodic.go.jp/) but currently only in Japanese.
In fact, the consequences of ignoring non-English science may be more serious than merely
lacking access to 36% of existing information; it can cause biases and gaps in our understand-
ing of the global environment. One potential bias in systematic reviews of English-language
journals is the over-representation of positive and/or statistically significant results , as they
are more likely to be published in high-impact English journals. Another type of bias, of partic-
ular relevance to environmental sciences, is that information on species, habitats, ecosystems,
and phenomena that are specific to countries where English is not the mother tongue can be
Fig 2. Waffle plots of (A) the use of an English title and an English abstract in 94 scientific documents written in Spanish (sampled from the
9,520 documents searched in Fig 1); document types of (B) the 46 documents with neither an English title nor an English abstract and (C)
those with an English title and/or an English abstract. Each square represents one document.
PLOS Biology | DOI:10.1371/journal.pbio.2000933 December 29, 2016 3 / 8
overlooked when searched only in English, as also reported in medical sciences . As an
example, the latest estimates of population status in Taiwan for fairy pittas (Pitta nympha), a
bird species of conservation concern, are available only in traditional Chinese (http://www.
wracb.gov.tw/public/DownLoads/20157161639457055.pdf) and not used in the global assess-
ment by the International Union for Conservation of Nature (Chie-Jen Ko, personal commu-
nications). Similarly, important papers reporting the infection of pigs with avian influenza
viruses in China initially went unnoticed by international communities, including the World
Health Organization and the United Nations Food and Agriculture Organization, because
they were published in Chinese-language journals . Also, there is a recognized knowledge
gap about the effects on biodiversity of some crops, such as soybeans, sorghum, and cotton ,
Fig 3. Waffle plots of (A) the use of an English title and an English abstract in 80 scientific documents written in Japanese (sampled from the
474 documents searched in Fig 1); document types of (B) the 28 documents with neither an English title nor an English abstract and (C) those
with an English title and/or an English abstract. Each square represents one document.
PLOS Biology | DOI:10.1371/journal.pbio.2000933 December 29, 2016 4 / 8
but considering that these crops are grown over large areas in South America and China, sci-
entific literature on these crops may exist in the local languages of these regions. Finally, scien-
tific knowledge generated by those undertaking conservation activities in the field (field
practitioners) could also be under-represented in English, as field practitioners often find it a
challenge to have their work published in academic journals , particularly in English if they
are non-native English speakers . This potentially renders local and indigenous knowledge
unavailable in English. For example, Wetlands International Argentina has produced over 20
technical publications on the conservation and management of wetlands over the past 20
years, but only 2 are available in English (Daniel E. Blanco, personal communications). Their
non-English publications include a report on the roles of peatlands, a wetland type of potential
global importance, in mitigating climate change impacts (http://lac.wetlands.org/Portals/4/
Turberas/Factbook%20Turberas%20de%20TdF%202010.pdf). Such knowledge generated by
practitioners is often overlooked as grey literature but forms a vital part of the evidence base
. For instance, the IPBES has recently shown that local and indigenous knowledge is a key
to understanding the conservation of ecosystem services by pollinators (http://www.ipbes.net/
Another consequence of language barriers that is becoming increasingly important operates
in the opposite direction: much scientific knowledge is now unavailable in local languages, as
publication in English has become prevalent. A factor behind this is that even scientists whose
mother tongue is not English aim to produce papers in English for publication in high-impact
journals given the clear advantages for their careers . Furthermore, many journals, previ-
ously published in local languages, are now publishing mainly in English to increase their
impacts on scientific communities globally (e.g., Animal Biodiversity and Conservation in
Spain, Natureza & Conservação in Brazil). As a consequence, there exists an imbalance in
knowledge transfer in countries where English is not the mother tongue; much scientific
knowledge that has originated there and elsewhere is available only in English and not in their
The increase in the proportion of conservation-related papers published in English has
helped global English-speaking communities access a broader range of information but, at the
same time, potentially raised the barrier for local practitioners and policy makers whose
mother tongue is not English. Leaving this problem unresolved is untenable if we consider that
areas experiencing a rapid loss of biodiversity and thus in the greatest need of information,
education, and conservation practices are often places where English is not spoken widely
. The last decade has seen an explosion of papers urging conservation communities to
tackle research-implementation gaps (e.g., ), but language barriers can further widen these
gaps. Conservation science needs to deliver local-level, species-specific evidence to on-site
practitioners and policy makers, but many practitioners often find language a barrier when
accessing primary scientific information [4,11]. For example, our survey with 44 national and
regional protected areas in Spain revealed that 54% of the directors (13 out of the 24 who
responded to our survey) identified languages as a barrier to the use of scientific papers as an
information source for management. Thus, although the extent of such language barriers
should vary among countries and individuals, depending on their proficiency in English, sim-
ply providing scientific knowledge in easily understandable and accessible ways, but in
English, might not make a difference for many practitioners and policy makers.
Transcending language barriers requires societal, institutional, and individual-level
changes. We should not assume that all important information is available in English. When
conducting systematic reviews or developing databases at a global scale, one simple, yet rarely
adopted, solution would be to include in the discussion speakers of a wide range of languages
(e.g., at least Spanish, Portuguese, Chinese, and French, which, in theory, altogether cover the
PLOS Biology | DOI:10.1371/journal.pbio.2000933 December 29, 2016 5 / 8
vast majority of non-English scientific documents; Fig 1). Particularly in influential global
assessments, like those by the IPBES, scientific literature published in non-English languages
should be equally considered and, if appropriate, included. We obviously need to ensure the
quality of literature to be included in such assessments; involving native speaker(s) of each lan-
guage would also facilitate this process. To this end, the website ConservationEvidence.com is
establishing an international panel to extract non-English language papers on conservation
interventions. In situations in which this approach is impractical, the use of non-English
search terms would help identify relevant non-English literature, although it is still not a com-
mon practice. We also suggest developing a database of major non-English journals in the dis-
cipline (a partial list is shown in S1 Table for conservation science). Such a database can be
accompanied by the registration of investigators working on a particular topic so that even
nonindexed works can be shared, as suggested and implemented in medical sciences [5,14],
and relevant papers can be disseminated in English via, for example, Social Network Services.
Authors of non-English language papers could also try to increase the visibility of their papers
by uploading preprints or postprints with the titles and abstracts in English on well-recognized
online repositories (see below).
A key to facilitating the application of scientific knowledge expressed in English to local
environmental issues is multilingualization of the knowledge. While English plays a crucial
role in the current publishing systems by centralizing scientific knowledge, we also need a sys-
tem for effectively redistributing the compiled knowledge to its users. We propose that all
authors be requested to provide lay summaries when publishing their papers in relevant con-
servation journals. The journals could then provide translations of those summaries in multi-
ple languages. This would dramatically increase accessibility to scientific knowledge for
practitioners and policy makers, as knowledge is provided regularly at a specific location(s) in
an easily understandable way. It would be even more influential if major journals in the subject
area could establish a common website. Translation costs could be covered by either journals
or authors depending on funding availability, in the same way that several open access journals
offer full or partial waivers to overcome any financial barriers to publication. Another, though
less influential, approach is to encourage individual researchers to provide translations of their
papers, for example, as supporting information of the original English papers (PLOS journals
and Conservation Biology allow this [15,16]; see S1–S5 Abstracts for the lay summary of this
paper in Spanish, Portuguese, French, simplified Chinese, and Japanese) or through self-
archiving on institutional or other repositories under appropriate copyright conditions. For
instance, submissions in multiple languages and translations of previously published work are
accepted in arXiv (https://arxiv.org/help/faq/multilang,http://arxiv.org/help/translations), fig-
share (confirmed on 23 February 2016), and PeerJ (confirmed on 15 March 2016). For the
translation of scientific books, a successful business model has already been proposed ,
which could be adopted widely.
While outreach activities have recently been advocated in science, it is still rare for such
activities to involve communication across language barriers. Institutions could give credit to
efforts by researchers to translate their findings into local languages in a similar way to how
other outreach activities are evaluated, particularly if the research covers issues at the global
scale or regions where English is not the mother tongue. Funding bodies and societies can
encourage researchers to use their funding for multilingualization; plans to overcome language
barriers, where appropriate, can be a criterion for evaluating outreach activities in grant pro-
posals (e.g., the British Ecological Society’s Outreach Grants and the National Science Founda-
tion’s Broader Impacts Review Criterion). As facilitating the translation of English knowledge
to a local language can benefit the local community, this could also attract the attention of
local funders .
PLOS Biology | DOI:10.1371/journal.pbio.2000933 December 29, 2016 6 / 8
Language barriers continue to impede the global compilation and application of scientific
knowledge. Overcoming this problem is not an easy challenge, but when achieved should have
far-reaching benefits to both scientists and users of scientific information in tackling global
environmental changes and solving local environmental issues. We believe the approaches
described here offer potential practical solutions.
S1 Table. Number of scientific documents in 16 languages.
S1 Abstract. Alternative Language Abstract in Spanish.
S2 Abstract. Alternative Language Abstract in Portuguese.
S3 Abstract. Alternative Language Abstract in French.
S4 Abstract. Alternative Language Abstract in simplified Chinese.
S5 Abstract. Alternative Language Abstract in Japanese.
Thanks to our colleagues for their advice on publications in local languages and opinions on
language barriers: J. M. Ochoa-Quintero (Spanish and Portuguese), V. Zamora-Gutierrez, D.
E. Blanco (Spanish), I. Catry (Portugese), M. Chen (simplified Chinese), J.-L. Martin, M. Som-
veille, A.-S. Bonnet-Lebrun (French), A. Basset, I. Rosati, N. Baccetti (Italian), J. Schleicher
(German and French), S. Lee and H. Park (Korean), L. Svensson (Swedish), C.-J. Ko (tradi-
tional Chinese), H. Ambarli (Turkish), P. Skorka (Polish), E. Nourani (Persian), I. Khorozyan
(Russian), and S. Duijns (Dutch). We also thank the protected area directors in Spain who
responded to our survey and M. Amano for all the support.
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