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Systematics and natural history of Southeast Asian Rock Geckos (genus Cnemaspis Strauch, 1887) with descriptions of eight new species from Malaysia, Thailand, and Indonesia

Grismer LL, Wood PL, Anuar S, Riyanto A, Ahmad N, Muin MA, et al.

Zootaxa, 2014;3880:1-147.
PMID: 25544645 DOI: 10.11646/zootaxa.3880.1.1

A well-supported and well-resolved phylogeny based on a concatenated data set from one mitochondrial and two nuclear genes, six morphological characters, and nine color pattern characters for 44 of the 50 species of the Southeast Asian Rock Geckos (genus Cnemaspis Strauch, 1887) is consistent with the previous taxonomy of Cnemaspis based solely on morphology and color pattern. Cnemaspis is partitioned into four major clades that collectively contain six species groups. The monophyly of all clades and species groups is strongly supported and they are parapatrically distributed across well-established, biogeographical regions ranging from southern Vietnam westward through southern Indochina, southward through the Thai-Malay Peninsula, then eastward to Borneo. Eight new species (Cnemaspis omari sp. nov. from the Thai-Malaysian border; C. temiah sp. nov. from Cameron Highlands, Pahang, Malaysia; C. stongensis sp. nov. from Gunung Stong, Kelantan, Malaysia; C. hangus sp. nov. from Bukit Hangus, Pahang, Malaysia; C. sundagekko sp. nov. from Pulau Siantan, Indonesia; C. peninsularis sp. nov. from southern Peninsular Malaysia and Singapore, and C. mumpuniae sp. nov. and C. sundainsula sp. nov. from Pulau Natuna Besar, Indonesia) are described based on morphology and color pattern and all but C. sundagekko sp. nov. are included in the phylogenetic analyses. Cnemaspis kendallii is polyphyletic and a composite of six species. An updated taxonomy consistent with the phylogeny is proposed for all 50 species and is based on 25 morphological and 53 color pattern characters scored across 594 specimens. Cladogenetic events and biogeographical relationships within Cnemaspis were likely influenced by this group's low vagility and the cyclical patterns of geographical and environmental changes in Sundaland over the last 25 million years and especially within the last 2.5 million years. The phylogeny indicates that nocturnality, diurnality, substrate preferences, and the presence of ocelli in the shoulder regions have evolved independently multiple times.

Matched MeSH terms: Geography
Systematic placement of an enigmatic Southeast Asian taxon Eupetes macrocerus and implications for the biogeography of a main songbird radiation, the Passerida

Jønsson KA, Fjeldså J, Ericson PG, Irestedt M

Biol Lett, 2007 Jun 22;3(3):323-6.
PMID: 17347105

Biogeographic connections between Australia and other continents are still poorly understood although the plate tectonics of the Indo-Pacific region is now well described. Eupetes macrocerus is an enigmatic taxon distributed in a small area on the Malay Peninsula and on Sumatra and Borneo. It has generally been associated with Ptilorrhoa in New Guinea on the other side of Wallace's Line, but a relationship with the West African Picathartes has also been suggested. Using three nuclear markers, we demonstrate that Eupetes is the sister taxon of the South African genus Chaetops, and their sister taxon in turn being Picathartes, with a divergence in the Eocene. Thus, this clade is distributed in remote corners of Africa and Asia, which makes the biogeographic history of these birds very intriguing. The most parsimonious explanation would be that they represent a relictual basal group in the Passerida clade established after a long-distance dispersal from the Australo-Papuan region to Africa. Many earlier taxonomic arrangements may have been based on assumptions about relationships with similar-looking forms in the same, or adjacent, biogeographic regions, and revisions with molecular data may uncover such cases of neglect of ancient relictual patterns reflecting past connections between the continents.

Matched MeSH terms: Geography
System of cities dynamics in newly industrializing nations

Meyer DR

Stud Comp Int Dev, 1986;21(1):3-22.
PMID: 12314582
Matched MeSH terms: Geography
Fulltext Synergies for improving oil palm production and forest conservation in floodplain landscapes

Abram NK, Xofis P, Tzanopoulos J, MacMillan DC, Ancrenaz M, Chung R, et al.

PLoS One, 2014;9(6):e95388.
PMID: 24887555 DOI: 10.1371/journal.pone.0095388

Lowland tropical forests are increasingly threatened with conversion to oil palm as global demand and high profit drives crop expansion throughout the world's tropical regions. Yet, landscapes are not homogeneous and regional constraints dictate land suitability for this crop. We conducted a regional study to investigate spatial and economic components of forest conversion to oil palm within a tropical floodplain in the Lower Kinabatangan, Sabah, Malaysian Borneo. The Kinabatangan ecosystem harbours significant biodiversity with globally threatened species but has suffered forest loss and fragmentation. We mapped the oil palm and forested landscapes (using object-based-image analysis, classification and regression tree analysis and on-screen digitising of high-resolution imagery) and undertook economic modelling. Within the study region (520,269 ha), 250,617 ha is cultivated with oil palm with 77% having high Net-Present-Value (NPV) estimates ($413/ha-yr-$637/ha-yr); but 20.5% is under-producing. In fact 6.3% (15,810 ha) of oil palm is commercially redundant (with negative NPV of $-299/ha-yr-$-65/ha-yr) due to palm mortality from flood inundation. These areas would have been important riparian or flooded forest types. Moreover, 30,173 ha of unprotected forest remain and despite its value for connectivity and biodiversity 64% is allocated for future oil palm. However, we estimate that at minimum 54% of these forests are unsuitable for this crop due to inundation events. If conversion to oil palm occurs, we predict a further 16,207 ha will become commercially redundant. This means that over 32,000 ha of forest within the floodplain would have been converted for little or no financial gain yet with significant cost to the ecosystem. Our findings have globally relevant implications for similar floodplain landscapes undergoing forest transformation to agriculture such as oil palm. Understanding landscape level constraints to this crop, and transferring these into policy and practice, may provide conservation and economic opportunities within these seemingly high opportunity cost landscapes.

Matched MeSH terms: Geography
Swamp row bogs down Singapore's bid to reclaim land

Cyranoski D

Nature, 2003 Dec 11;426(6967):592.
PMID: 14668824
Matched MeSH terms: Geography
Sustained growth but non-sustainable urbanisation in Penang, Malaysia

Fold N, Wangel A

Third World Plann Rev, 1998 May;20(2):165-77.
PMID: 12295215
Matched MeSH terms: Geography
Fulltext Sustainable management in crop monocultures: the impact of retaining forest on oil palm yield

Edwards FA, Edwards DP, Sloan S, Hamer KC

PLoS One, 2014;9(3):e91695.
PMID: 24638038 DOI: 10.1371/journal.pone.0091695

Tropical agriculture is expanding rapidly at the expense of forest, driving a global extinction crisis. How to create agricultural landscapes that minimise the clearance of forest and maximise sustainability is thus a key issue. One possibility is protecting natural forest within or adjacent to crop monocultures to harness important ecosystem services provided by biodiversity spill-over that may facilitate production. Yet this contrasts with the conflicting potential that the retention of forest exports dis-services, such as agricultural pests. We focus on oil palm and obtained yields from 499 plantation parcels spanning a total of ≈23,000 ha of oil palm plantation in Sabah, Malaysian Borneo. We investigate the relationship between the extent and proximity of both contiguous and fragmented dipterocarp forest cover and oil palm yield, controlling for variation in oil palm age and for environmental heterogeneity by incorporating proximity to non-native forestry plantations, other oil palm plantations, and large rivers, elevation and soil type in our models. The extent of forest cover and proximity to dipterocarp forest were not significant predictors of oil palm yield. Similarly, proximity to large rivers and other oil palm plantations, as well as soil type had no significant effect. Instead, lower elevation and closer proximity to forestry plantations had significant positive impacts on oil palm yield. These findings suggest that if dipterocarp forests are exporting ecosystem service benefits or ecosystem dis-services, that the net effect on yield is neutral. There is thus no evidence to support arguments that forest should be retained within or adjacent to oil palm monocultures for the provision of ecosystem services that benefit yield. We urge for more nuanced assessments of the impacts of forest and biodiversity on yields in crop monocultures to better understand their role in sustainable agriculture.

Matched MeSH terms: Geography
Fulltext Sustainable Palm Oil-The Role of Screening and Advanced Analytical Techniques for Geographical Traceability and Authenticity Verification

Ramli US, Tahir NI, Rozali NL, Othman A, Muhammad NH, Muhammad SA, et al.

Molecules, 2020 Jun 25;25(12).
PMID: 32630515 DOI: 10.3390/molecules25122927

Palm oil production from oil palm (Elaeis guineensis Jacq.) is vital for the economy of Malaysia. As of late, sustainable production of palm oil has been a key focus due to demand by consumer groups, and important progress has been made in establishing standards that promote good agricultural practices that minimize impact on the environment. In line with the industrial goal to build a traceable supply chain, several measures have been implemented to ensure that traceability can be monitored. Although the palm oil supply chain can be highly complex, and achieving full traceability is not an easy task, the industry has to be proactive in developing improved systems that support the existing methods, which rely on recorded information in the supply chain. The Malaysian Palm Oil Board (MPOB) as the custodian of the palm oil industry in Malaysia has taken the initiative to assess and develop technologies that can ensure authenticity and traceability of palm oil in the major supply chains from the point of harvesting all the way to key downstream applications. This review describes the underlying framework related to palm oil geographical traceability using various state-of-the-art analytical techniques, which are also being explored to address adulteration in the global palm oil supply chain.

Matched MeSH terms: Geography
Fulltext Survival Rate and Transcriptional Response upon Infection with the Generalist Parasite Beauveria bassiana in a World-Wide Sample of Drosophila melanogaster

Paparazzo F, Tellier A, Stephan W, Hutter S

PLoS One, 2015;10(7):e0132129.
PMID: 26154519 DOI: 10.1371/journal.pone.0132129

The ability to cope with infection by a parasite is one of the major challenges for any host species and is a major driver of evolution. Parasite pressure differs between habitats. It is thought to be higher in tropical regions compared to temporal ones. We infected Drosophila melanogaster from two tropical (Malaysia and Zimbabwe) and two temperate populations (the Netherlands and North Carolina) with the generalist entomopathogenic fungus Beauveria bassiana to examine if adaptation to local parasite pressures led to differences in resistance. Contrary to previous findings we observed increased survival in temperate populations. This, however, is not due to increased resistance to infection per se, but rather the consequence of a higher general vigor of the temperate populations. We also assessed transcriptional response to infection within these flies eight and 24 hours after infection. Only few genes were induced at the earlier time point, most of which are involved in detoxification. In contrast, we identified more than 4,000 genes that changed their expression state after 24 hours. This response was generally conserved over all populations with only few genes being uniquely regulated in the temperate populations. We furthermore found that the American population was transcriptionally highly diverged from all other populations concerning basal levels of gene expression. This was particularly true for stress and immune response genes, which might be the genetic basis for their elevated vigor.

Matched MeSH terms: Geography
Fulltext Survey on Heavy Metals Contamination and Health Risk Assessment in Commercially Valuable Asian Swamp Eel, Monopterus albus from Kelantan, Malaysia

Sow AY, Ismail A, Zulkifli SZ, Amal MN, Hambali KA

Sci Rep, 2019 04 23;9(1):6391.
PMID: 31015502 DOI: 10.1038/s41598-019-42753-2

This work investigates the metals concentration in the tissues of Asian swamp eel, Monopterus albus. Five selected tissues, including liver, gill, bone, skin, and muscle were examined for the concentration of Zn, Cu, Cd, Pb, and Ni. The concentrations of Cd and Pb were found high in the muscle tissues of the eels. Additionally, high amounts of Zn and Cu metals were observed in the liver, whereas the Cd, Pb, and Ni metals were highly detected in gill. The accumulation of Zn, Cu, Cd, Pb, and Ni in both skin and bone of the eel seems to vary between seasons. Low levels of Zn, Cu, and Ni were identified in the muscle tissues of the eels. This study revealed that the concentration of Cd and Pb in the muscle tissues of Asian swamp eels exceeded the permissible limits by the US EPA, suggesting the consumption of the muscle may be hazardous and can severely affect one's health.

Matched MeSH terms: Geography
Fulltext Sumatran tiger survival threatened by deforestation despite increasing densities in parks

Luskin MS, Albert WR, Tobler MW

Nat Commun, 2017 12 05;8(1):1783.
PMID: 29208916 DOI: 10.1038/s41467-017-01656-4

The continuing development of improved capture-recapture (CR) modeling techniques used to study apex predators has also limited robust temporal and cross-site analyses due to different methods employed. We develop an approach to standardize older non-spatial CR and newer spatial CR density estimates and examine trends for critically endangered Sumatran tigers (Panthera tigris sumatrae) using a meta-regression of 17 existing densities and new estimates from our own fieldwork. We find that tiger densities were 47% higher in primary versus degraded forests and, unexpectedly, increased 4.9% per yr from 1996 to 2014, likely indicating a recovery from earlier poaching. However, while tiger numbers may have temporarily risen, the total potential island-wide population declined by 16.6% from 2000 to 2012 due to forest loss and degradation and subpopulations are significantly more fragmented. Thus, despite increasing densities in smaller parks, we conclude that there are only two robust populations left with >30 breeding females, indicating Sumatran tigers still face a high risk of extinction unless deforestation can be controlled.

Matched MeSH terms: Geography
Studies on the nematode parasites of Malaysian rodents. I. The Rhabdiasidea, Trichuridea and Oxyuridea

Ow-Yang CK

J Helminthol, 1971;45(2):93-109.
PMID: 5123705
Matched MeSH terms: Geography
Stories and maps, images and archives: multimethod approach to the political ecology of native property rights and natural resource management in Sabah, Malaysia

Doolittle AA

Environ Manage, 2010 Jan;45(1):67-81.
PMID: 18506515 DOI: 10.1007/s00267-008-9144-0

The study of human-environmental relations is complex and by nature draws on theories and practices from multiple disciplines. There is no single research strategy or universal set of methods to which researchers must adhere. Particularly for scholars interested in a political ecology approach to understanding human-environmental relationships, very little has been written examining the details of "how to" design a project, develop appropriate methods, produce data, and, finally, integrate multiple forms of data into an analysis. A great deal of attention has been paid, appropriately, to the theoretical foundations of political ecology, and numerous scholarly articles and books have been published recently. But beyond Andrew Vayda's "progressive contextualization" and Piers Blaikie and Harold Brookfield's "chains of explanation," remarkably little is written that provides a research model to follow, modify, and expand. Perhaps one of the reasons for this gap in scholarship is that, as expected in interdisciplinary research, researchers use a variety of methods that are suitable (and perhaps unique) to the questions they are asking. To start a conversation on the methods available for researchers interested in adopting a political ecology perspective to human-environmental interactions, I use my own research project as a case study. This research is by no means flawless or inclusive of all possible methods, but by using the details of this particular research process as a case study I hope to provide insights into field research that will be valuable for future scholarship.

Matched MeSH terms: Geography
Speciation, faunal affinities and geographical dispersal of black flies (Diptera: Simuliidae) in the Oriental Region

Takaoka H

Acta Trop, 2017 Feb;166:234-240.
PMID: 27890608 DOI: 10.1016/j.actatropica.2016.11.027

The simuliid fauna of the Oriental Region is reviewed in comparison with those in five other zoogeographical regions. It is relatively young, represented by only one genus Simulium, which is regarded as the most specialized among 26 genera of the family Simuliidae. The Oriental Region has the second largest simuliid fauna with 524 species or 23.8% of the world total of 2204 extant species. This species richness is associated with a high speciation index (15.4), reflected especially by the high speciation rates of two dominant subgenera Gomphostilbia and Simulium although the number of lineages in the Oriental Region is moderate (34 or 20.6% of the total 165). The Oriental fauna has relationships with all other zoogeographical regions at the lineage level, having the highest affinity index (31.9) with the Palearctic Region. It is inferred that eight of 10 Oriental subgenera moved during the ice ages from the Palaearctic to the Oriental Regions; the subgenus Gomphostilbia evolved into 11 species-groups and underwent species radiation in the Oriental Region. On the other hand, two other subgenera, Nevermannia and Simulium, moved southward during the ice ages after evolving into species-groups. In the post-ice ages, most lineages retreated northward, with different portions of species left in the Oriental Region, although some lineages failed to retreat and survived as relict lineages in the Oriental Region.

Matched MeSH terms: Geography
Speciation and phylogeography of the Southeast Asian Anopheles sundaicus complex

Dusfour I, Michaux JR, Harbach RE, Manguin S

Infect Genet Evol, 2007 Jul;7(4):484-93.
PMID: 17350896

Anopheles sundaicus s.l. is a malaria vector in coastal areas of Southeast Asia. Previous studies showed at least four distinct species within the complex. The present study investigated the phylogeography and the status of A. sundaicus s.l. populations from Cambodia, Thailand, Malaysia and Indonesia with regard to A. sundaicus s.s. from Sarawak, Malaysian Borneo and A. epiroticus in Vietnam and Thailand. Three lineages recovered by analyses of Cyt-b and COI (mtDNA) confirmed the presence of A. sundaicus s.s. in Malaysian Borneo, the distribution of A. epiroticus from southern Vietnam to peninsular Malaysia, and recognised a distinct form in Indonesia that is named A. sundaicus E. The phylogenetic and demographic analyses suggest that the three species were separated during the Early Pleistocene (1.8-0.78 Myr) and experienced bottlenecks followed by a genetic expansion in more recent times. Based on the results and knowledge of the biogeography of the area, we hypothesise that the combination of cyclical island and refugium creation was the cause of lineage isolation and bottleneck events during the Pleistocene.

Matched MeSH terms: Geography*
Spatiotemporal mapping of cervical cancer incidence highlights need for targeted prevention in Songkhla province, Thailand

Zhao J, Virani S, Sriplung H

Health Policy Plan, 2017 Apr 01;32(3):430-436.
PMID: 27935803 DOI: 10.1093/heapol/czw145

Background: The national cervical cancer screening program in Thailand has been successful in reducing overall burden from this disease. However, evaluation on spatial and temporal scales is needed to assess the efficacy of this program in smaller regions. Here, we geographically assess incidence in a province with a uniquely heterogeneous distribution of lifestyle factors associated with religiosity.
Methods: Cervical cancer cases were extracted from the provincial cancer registry from 1989 to 2013. Age-adjusted incidence rates were calculated using population statistics from the census bureau and adjusted to the Segi world standard population. Bayesian hierarchical modelling was employed to spatiotemporally map cervical cancer incidence trends in Songkhla province in 5-year period.
Results: Overall, the incidence of cervical cancer decreased in Songkhla province. The three districts with a Muslim population of greater than 70% had consistently lower cervical cancer rates from 1989 to 2013 compared with the rest of the predominantly Buddhist districts. Hotspots of incidence were identified in Sadao, Hat Yai and the juncture of Mueang Songkhla and Singhanakhon in each 5-year period.
Conclusions: Distinct cervical cancer incidence trends by religion over time indicate differences in sexual habits, lifestyle and religion-associated culture between Muslims and Buddhists, and suggest divergent risk factor profiles for these groups. The high incidence rates in Sadao and Hat Yai is likely explained by the main road to Malaysia, which runs across these two areas and has frequent commercial sex trade. Female sex workers should be targeted as a vulnerable population for screening efforts to address this continuing burden of cervical cancer.

Matched MeSH terms: Geography, Medical/methods*
Fulltext Spatio-temporal ecology of sympatric felids on Borneo. Evidence for resource partitioning?

Hearn AJ, Cushman SA, Ross J, Goossens B, Hunter LTB, Macdonald DW

PLoS One, 2018;13(7):e0200828.
PMID: 30028844 DOI: 10.1371/journal.pone.0200828

Niche differentiation, the partitioning of resources along one or more axes of a species' niche hyper-volume, is widely recognised as an important mechanism for sympatric species to reduce interspecific competition and predation risk, and thus facilitate co-existence. Resource partitioning may be facilitated by behavioural differentiation along three main niche dimensions: habitat, food and time. In this study, we investigate the extent to which these mechanisms can explain the coexistence of an assemblage of five sympatric felids in Borneo. Using multi-scale logistic regression, we show that Bornean felids exhibit differences in both their broad and fine-scale habitat use. We calculate temporal activity patterns and overlap between these species, and present evidence for temporal separation within this felid guild. Lastly, we conducted an all-subsets logistic regression to predict the occurrence of each felid species as a function of the co-occurrence of a large number of other species and showed that Bornean felids co-occurred with a range of other species, some of which could be candidate prey. Our study reveals apparent resource partitioning within the Bornean felid assemblage, operating along all three niche dimension axes. These results provide new insights into the ecology of these species and the broader community in which they live and also provide important information for conservation planning for this guild of predators.

Matched MeSH terms: Geography
Fulltext Spatially explicit trends in the global conservation status of vertebrates

Rodrigues AS, Brooks TM, Butchart SH, Chanson J, Cox N, Hoffmann M, et al.

PLoS One, 2014;9(11):e113934.
PMID: 25426636 DOI: 10.1371/journal.pone.0113934

The world's governments have committed to preventing the extinction of threatened species and improving their conservation status by 2020. However, biodiversity is not evenly distributed across space, and neither are the drivers of its decline, and so different regions face very different challenges. Here, we quantify the contribution of regions and countries towards recent global trends in vertebrate conservation status (as measured by the Red List Index), to guide action towards the 2020 target. We found that>50% of the global deterioration in the conservation status of birds, mammals and amphibians is concentrated in <1% of the surface area, 39/1098 ecoregions (4%) and eight/195 countries (4%) - Australia, China, Colombia, Ecuador, Indonesia, Malaysia, Mexico, and the United States. These countries hold a third of global diversity in these vertebrate groups, partially explaining why they concentrate most of the losses. Yet, other megadiverse countries - most notably Brazil (responsible for 10% of species but just 1% of deterioration), plus India and Madagascar - performed better in conserving their share of global vertebrate diversity. Very few countries, mostly island nations (e.g. Cook Islands, Fiji, Mauritius, Seychelles, and Tonga), have achieved net improvements. Per capita wealth does not explain these patterns, with two of the richest countries - United States and Australia - fairing conspicuously poorly. Different countries were affected by different combinations of threats. Reducing global rates of biodiversity loss will require investment in the regions and countries with the highest responsibility for the world's biodiversity, focusing on conserving those species and areas most in peril and on reducing the drivers with the highest impacts.

Matched MeSH terms: Geography
Fulltext Spatial subsidies drive sweet spots of tropical marine biomass production

Morais RA, Siqueira AC, Smallhorn-West PF, Bellwood DR

PLoS Biol, 2021 Nov;19(11):e3001435.
PMID: 34727097 DOI: 10.1371/journal.pbio.3001435

Spatial subsidies increase local productivity and boost consumer abundance beyond the limits imposed by local resources. In marine ecosystems, deeper water and open ocean subsidies promote animal aggregations and enhance biomass that is critical for human harvesting. However, the scale of this phenomenon in tropical marine systems remains unknown. Here, we integrate a detailed assessment of biomass production in 3 key locations, spanning a major biodiversity and abundance gradient, with an ocean-scale dataset of fish counts to predict the extent and magnitude of plankton subsidies to fishes on coral reefs. We show that planktivorous fish-mediated spatial subsidies are widespread across the Indian and Pacific oceans and drive local spikes in biomass production that can lead to extreme productivity, up to 30 kg ha-1 day-1. Plankton subsidies form the basis of productivity "sweet spots" where planktivores provide more than 50% of the total fish production, more than all other trophic groups combined. These sweet spots operate at regional, site, and smaller local scales. By harvesting oceanic productivity, planktivores bypass spatial constraints imposed by local primary productivity, creating "oases" of tropical fish biomass that are accessible to humans.

Matched MeSH terms: Geography
Fulltext Spatial structure of seagrass suggests that size-dependent plant traits have a strong influence on the distribution and maintenance of tropical multispecies meadows

Ooi JL, Van Niel KP, Kendrick GA, Holmes KW

PLoS One, 2014;9(1):e86782.
PMID: 24497978 DOI: 10.1371/journal.pone.0086782

Seagrass species in the tropics occur in multispecies meadows. How these meadows are maintained through species co-existence and what their ecological drivers may be has been an overarching question in seagrass biogeography. In this study, we quantify the spatial structure of four co-existing species and infer potential ecological processes from these structures.

Matched MeSH terms: Geography

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