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The Role of Thailand in the International Trade in CITES-Listed Live Reptiles and Amphibians
Vincent Nijman,Chris R. Shepherd
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0017825
Abstract: International wildlife trade is one of the leading threats to biodiversity conservation. The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) is the most important initiative to monitor and regulate the international trade of wildlife but its credibility is dependent on the quality of the trade data. We report on the performance of CITES reporting by focussing on the commercial trade in non-native reptiles and amphibians into Thailand as to illustrate trends, species composition and numbers of wild-caught vs. captive-bred specimens.
Aggression and dominance in cichlids in resident-intruder tests: the role of environmental enrichment
Nijman, Vincent;Heuts, Boudewijn A.;
Neotropical Ichthyology , 2011, DOI: 10.1590/S1679-62252011005000031
Abstract: when establishing dominance residents have a greater likelihood to dominate intruders than vice versa, partially because the resident has more to loose that the intruder has to win. this is known as the prior residency effect. in environmentally rich environments this effect should be stronger than in poor environments. recently kadry & barreto (2010, neotrop ichthyol 8: 329-332) tested this in the pearl cichlid geophagus brasiliensis (17 test pairs) and reported that environmental enrichment led to a reduction of aggression. we here present data on four other cichlids (332 test pairs) showing a stronger prior residency effect in enriched conditions, and, for two species, an increase in aggression. we discuss possible reasons for the differences between studies, focussing on the relationship between aggression and dominance and sample size effects.
Aggression and dominance in cichlids in resident-intruder tests: the role of environmental enrichment
Vincent Nijman,Boudewijn A. Heuts
Neotropical Ichthyology , 2011,
Abstract: When establishing dominance residents have a greater likelihood to dominate intruders than vice versa, partially because the resident has more to loose that the intruder has to win. This is known as the prior residency effect. In environmentally rich environments this effect should be stronger than in poor environments. Recently Kadry & Barreto (2010, Neotrop Ichthyol 8: 329-332) tested this in the pearl cichlid Geophagus brasiliensis (17 test pairs) and reported that environmental enrichment led to a reduction of aggression. We here present data on four other cichlids (332 test pairs) showing a stronger prior residency effect in enriched conditions, and, for two species, an increase in aggression. We discuss possible reasons for the differences between studies, focussing on the relationship between aggression and dominance and sample size effects. No estabelecimento de dominancia, residentes têm uma maior probabilidade de dominar os intrusos que vice-versa, em parte porque o residente tem mais a perder que o invasor tem a ganhar. Isto é conhecido como o efeito de residência prévia. Em ambientes ecologicamente ricos esse efeito deve ser mais forte do que em ambientes pobres. Recentemente Kadry & Barreto (2010, Neotrop. Ichthyol. 8: 329-332) testaram isso no cará Geophagus brasiliensis (17 pares de teste) e relataram que o enriquecimento ambiental levou a uma redu o de agress o. Aqui apresentamos dados de quatro outros ciclídeos (332 pares de teste), mostrando um efeito mais forte de residência prévia em condi es enriquecidas, e, para duas espécies, o aumento da agress o. Discutimos possíveis raz es para as diferen as entre os estudos, concentrando-nos sobre a rela o entre agress o e domina o e os efeitos do tamanho da amostra.
Molecular Identification of Birds: Performance of Distance-Based DNA Barcoding in Three Genes to Delimit Parapatric Species
Mansour Aliabadian, Mohammad Kaboli, Vincent Nijman, Miguel Vences
PLOS ONE , 2009, DOI: 10.1371/journal.pone.0004119
Abstract: Background DNA barcoding based on the mitochondrial cytochrome oxidase subunit I gene (cox1 or COI) has been successful in species identification across a wide array of taxa but in some cases failed to delimit the species boundaries of closely allied allopatric species or of hybridising sister species. Methodology/Principal Findings In this study we extend the sample size of prior studies in birds for cox1 (2776 sequences, 756 species) and target especially species that are known to occur parapatrically, and/or are known to hybridise, on a Holarctic scale. In order to obtain a larger set of taxa (altogether 2719 species), we include also DNA sequences of two other mitochondrial genes: cytochrome b (cob) (4614 sequences, 2087 species) and 16S (708 sequences, 498 species). Our results confirm the existence of a wide gap between intra- and interspecies divergences for both cox1 and cob, and indicate that distance-based DNA barcoding provides sufficient information to identify and delineate bird species in 98% of all possible pairwise comparisons. This DNA barcoding gap was not statistically influenced by the number of individuals sequenced per species. However, most of the hybridising parapatric species pairs have average divergences intermediate between intraspecific and interspecific distances for both cox1 and cob. Conclusions/Significance DNA barcoding, if used as a tool for species discovery, would thus fail to identify hybridising parapatric species pairs. However, most of them can probably still assigned to known species by character-based approaches, although development of complementary nuclear markers will be necessary to account for mitochondrial introgression in hybridising species.
Contact and hybrid zone hotspots and evolution of birds in the Middle East

Mansour Aliabadian,Mohammad Kaboli,Bahram Kiabi,Vincent Nijman,

自然科学进展 , 2007,
Abstract: The Middle East is an important contact zone for a considerable number of bird taxa from the western and eastern Palearctic and from the great Saharo-Sindian desert belt. Using WORLDMAP software, we analyzed the geographical distribution of secondary contact zones for parapatric species pairs of birds in the Middle East. We identified 56 species (29 species pairs) that make contact in the Middle East. The species pairs belong to three orders, i.e. Falconiformes, Piciformes, and Passeriformes. Almost half (46%) of these species pairs hybridize in their contact zones. Although contact zones occur over a large part of northern Middle East, spatially they were not evenly distributed. Contact zone richness was highest in the mountain ranges south of the Caspian Sea and the Caucasus. The hottest hotspots, where up to nine bird species pairs occur sympatrically, are situated in north-eastern Iran and Azerbaijan. We discuss the relevance of these hotspots for improving our understanding of the biogeography and evolution of the avifauna in the Middle East.
Wildlife trade in Asia: start with the consumer
Diogo Veríssimo,Daniel W.S. Challender,Vincent Nijman
Asian Journal of Conservation Biology , 2012,
Abstract: EDITORIAL
Declining Orangutan Encounter Rates from Wallace to the Present Suggest the Species Was Once More Abundant
Erik Meijaard,Alan Welsh,Marc Ancrenaz,Serge Wich,Vincent Nijman,Andrew J. Marshall
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0012042
Abstract: Bornean orangutans (Pongo pygmaeus) currently occur at low densities and seeing a wild one is a rare event. Compared to present low encounter rates of orangutans, it is striking how many orangutan each day historic collectors like Alfred Russel Wallace were able to shoot continuously over weeks or even months. Does that indicate that some 150 years ago encounter rates with orangutans, or their densities, were higher than now?
Tickled to Death: Analysing Public Perceptions of ‘Cute’ Videos of Threatened Species (Slow Lorises – Nycticebus spp.) on Web 2.0 Sites
By K. Anne-Isola Nekaris, Nicola Campbell, Tim G. Coggins, E. Johanna Rode, Vincent Nijman
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069215
Abstract: Background The internet is gaining importance in global wildlife trade and changing perceptions of threatened species. There is little data available to examine the impact that popular Web 2.0 sites play on public perceptions of threatened species. YouTube videos portraying wildlife allow us to quantify these perceptions. Methodology/Principal Findings Focussing on a group of threatened and globally protected primates, slow lorises, we quantify public attitudes towards wildlife conservation by analysing 12,411 comments and associated data posted on a viral YouTube video ‘tickling slow loris’ over a 33-months period. In the initial months a quarter of commentators indicated wanting a loris as a pet, but as facts about their conservation and ecology became more prevalent this dropped significantly. Endorsements, where people were directed to the site by celebrities, resulted mostly in numerous neutral responses with few links to conservation or awareness. Two conservation-related events, linked to Wikipedia and the airing of a television documentary, led to an increase in awareness, and ultimately to the removal of the analysed video. Conclusions/Significance Slow loris videos that have gone viral have introduced these primates to a large cross-section of society that would not normally come into contact with them. Analyses of webometric data posted on the internet allow us quickly to gauge societal sentiments. We showed a clear temporal change in some views expressed but without an apparent increase in knowledge about the conservation plight of the species, or the illegal nature of slow loris trade. Celebrity endorsement of videos showing protected wildlife increases visits to such sites, but does not educate about conservation issues. The strong desire of commentators to express their want for one as a pet demonstrates the need for Web 2.0 sites to provide a mechanism via which illegal animal material can be identified and policed.
From Tumor Immunosuppression to Eradication: Targeting Homing and Activity of Immune Effector Cells to Tumors
Oana Draghiciu,Hans W. Nijman,Toos Daemen
Clinical and Developmental Immunology , 2011, DOI: 10.1155/2011/439053
Abstract: Unraveling the mechanisms used by the immune system to fight cancer development is one of the most ambitious undertakings in immunology. Detailed knowledge regarding the mechanisms of induction of tolerance and immunosuppression within the tumor microenvironment will contribute to the development of highly effective tumor eradication strategies. Research within the last few decades has shed more light on the matter. This paper aims to give an overview on the current knowledge of the main tolerance and immunosuppression mechanisms elicited within the tumor microenvironment, with the focus on development of effective immunotherapeutic strategies to improve homing and activity of immune effector cells to tumors.
From Tumor Immunosuppression to Eradication: Targeting Homing and Activity of Immune Effector Cells to Tumors
Oana Draghiciu,Hans W. Nijman,Toos Daemen
Journal of Immunology Research , 2011, DOI: 10.1155/2011/439053
Abstract: Unraveling the mechanisms used by the immune system to fight cancer development is one of the most ambitious undertakings in immunology. Detailed knowledge regarding the mechanisms of induction of tolerance and immunosuppression within the tumor microenvironment will contribute to the development of highly effective tumor eradication strategies. Research within the last few decades has shed more light on the matter. This paper aims to give an overview on the current knowledge of the main tolerance and immunosuppression mechanisms elicited within the tumor microenvironment, with the focus on development of effective immunotherapeutic strategies to improve homing and activity of immune effector cells to tumors. 1. General Introduction In the beginning of the 20th century, the concept according to which the immune system can be manipulated for tumor prevention or tumor treatment has emerged. Around half a century later, Burnet postulated the existence of a complex immunological mechanism capable of eliminating potentially malignant cells and, thus, gave birth to what would afterwards be called the cancer immunosurveillance theory [1]. In later years, strong evidence supporting the existence of intricate antitumor immune responses lead to the more exhaustive concept of cancer immunoediting. According to this concept, the multistep process of cancer development consists of three phases. The first phase, of elimination, is similar to the cancer immunosurveillance theory. Malignant cells, generated after genetic modifications that may occur during cell division cycles, present the singular property of expressing tumor antigens, a feature which makes them immunologically distinguishable from nonmalignant cells. Recognition of these tumor antigens by cells belonging to the host immune system leads to development of antitumor immune responses. Within the second phase, of equilibrium, a dynamic balance between the tumor microenvironment and the host immune responses is established. However, due to the negative activity of the tumor microenvironment as a dynamic inducer of immune cell anergy or death [2, 3], these antitumor immune responses are apparently insufficient to completely eradicate tumors. Hence, the third phase, of escape, consists of development of immune resistant tumor variants into fully grown and progressive clinical tumors [4, 5]. Here, the concept of cancer immunotherapy comes into play. Although the host immune system is clearly capable of recognizing cancer cells [6], the ability to which it can control tumor growth remains very limited.
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