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Phylogeny and biogeography of exacum (gentianaceae): a disjunctive distribution in the Indian ocean basin resulted from long distance dispersal and extensive radiation

Yuan YM, Wohlhauser S, Möller M, Klackenberg J, Callmander M, Küpfer P

Syst Biol, 2005 Feb;54(1):21-34.
PMID: 15805008

Disjunctive distributions across paleotropical regions in the Indian Ocean Basin (IOB) often invoke dispersal/vicariance debates. Exacum (Gentianaceae, tribe Exaceae) species are spread around the IOB, in Africa, Madagascar, Socotra, the Arabian peninsula, Sri Lanka, India, the Himalayas, mainland Southeast Asia including southern China and Malaysia, and northern Australia. The distribution of this genus was suggested to be a typical example of vicariance resulting from the breakup of the Gondwanan supercontinent. The molecular phylogeny of Exacum is in principle congruent with morphological conclusions and shows a pattern that resembles a vicariance scenario with rapid divergence among lineages, but our molecular dating analysis demonstrates that the radiation is too recent to be associated with the Gondwanan continental breakup. We used our dating analysis to test the results of DIVA and found that the program predicted impossible vicariance events. Ancestral area reconstruction suggests that Exacum originated in Madagascar, and divergence dating suggests its origin was not before the Eocene. The Madagascan progenitor, the most recent common ancestor of Exacum, colonized Sri Lanka and southern India via long-distance dispersals. This colonizer underwent an extensive range expansion and spread to Socotra-Arabia, northern India, and mainland Southeast Asia in the northern IOB when it was warm and humid in these regions. This widespread common ancestor retreated subsequently from most parts of these regions and survived in isolation in Socotra-Arabia, southern India-Sri Lanka, and perhaps mainland Southeast Asia, possibly as a consequence of drastic climatic changes, particularly the spreading drought during the Neogene. Secondary diversification from these surviving centers and Madagascar resulted in the extant main lineages of the genus. The vicariance-like pattern shown by the phylogeny appears to have resulted from long-distance dispersals followed by extensive range expansion and subsequent fragmentation. The extant African species E. oldenlandioides is confirmed to be recently dispersed from Madagascar.

Matched MeSH terms: Population Dynamics
Patterns of genetic diversity and migration in increasingly fragmented and declining orang-utan (Pongo pygmaeus) populations from Sabah, Malaysia

Goossens B, Chikhi L, Jalil MF, Ancrenaz M, Lackman-Ancrenaz I, Mohamed M, et al.

Mol Ecol, 2005 Feb;14(2):441-56.
PMID: 15660936

We investigated the genetic structure within and among Bornean orang-utans (Pongo pygmaeus) in forest fragments of the Lower Kinabatangan flood plain in Sabah, Malaysia. DNA was extracted from hair and faecal samples for 200 wild individuals collected during boat surveys on the Kinabatangan River. Fourteen microsatellite loci were used to characterize patterns of genetic diversity. We found that genetic diversity was high in the set of samples (mean H(E) = 0.74) and that genetic differentiation was significant between the samples (average F(ST) = 0.04, P < 0.001) with F(ST) values ranging from low (0.01) to moderately large (0.12) values. Pairwise F(ST) values were significantly higher across the Kinabatangan River than between samples from the same river side, thereby confirming the role of the river as a natural barrier to gene flow. The correlation between genetic and geographical distance was tested by means of a series of Mantel tests based on different measures of geographical distance. We used a Bayesian method to estimate immigration rates. The results indicate that migration is unlikely across the river but cannot be completely ruled out because of the limited F(ST) values. Assignment tests confirm the overall picture that gene flow is limited across the river. We found that migration between samples from the same side of the river had a high probability indicating that orang-utans used to move relatively freely between neighbouring areas. This strongly suggests that there is a need to maintain migration between isolated forest fragments. This could be done by restoring forest corridors alongside the river banks and between patches.

Matched MeSH terms: Population Dynamics
Fulltext POPULATION ABUNDANCE OF RED PALM WEEVIL, RHYNCHOPHORUS FERRUGINEUS (COLEOPTERA: DRYOPHTHORIDAE) IN RHU TAPAI COCONUT PLANTATION

Nurul Syafiqah Senafi, Nor Zalipah Mohamed

UMT Journal of Undergraduate Research, 2020;2(1):71-76.
MyJurnal

Red Palm Weevil (RPW), Rhynchophorus ferrugineus is a lethal pest which has been described as a serious pest that reduces the production of coconut tree and other major cultivated palms. RPW infestation was initially detected by Department of Agriculture (DOA) in 2007 in all eight Terengganu districts. Rhu Tapai plantation area is one of the highly infested areas in Terengganu. Until now, limited reports on population abundance of this lethal pest have been discussed particularly in Rhu Tapai. Therefore, a study on population abundance is a must in order to understand the population dynamic of RPW which will be the first step of its control strategy. A total of 12 traps were installed and synthetic pheromones (P028 Ferrolure+) were used in attracting the RPW adults. Overall, 81 individuals of RPW were successfully collected after 16 weeks of pheromone trapping (3rd September until 28th November 2018). The trend of weekly RPW captured was eventually decreasing from Week 1 to Week 16 but showed a sudden increment in Week 10. Pandan cultivar plot captured the highest number of adult RPW compared with Mawa cultivar plots. Result showed no significant difference between RPW sexes percentage of sexes which was 53% of male and 47% of female (1:1 ratio) (U= 0.143, p > 0.05). Daily rainfall and temperature significantly reduced the trapping efficiency (R²rainfall = 0.142, p = 0.145; R²temperature = 0.0858; p = 0.258). These results will be the baseline information for future study regarding control management strategy using pheromone-based mass trapping system.

Matched MeSH terms: Population Dynamics
PCR-RFLP analysis of mitochondrial DNA cytochrome b gene among Haruan (Channa striatus) in Malaysia

Rahim MH, Ismail P, Alias R, Muhammad N, Mat Jais AM

Gene, 2012 Feb 15;494(1):1-10.
PMID: 22197656 DOI: 10.1016/j.gene.2011.12.015

Haruan (Channa striatus) is in great demand in the Malaysian domestic fish market. In the present study, mtDNA cyt b was used to investigate genetic variation of C. striatus among populations in Peninsular Malaysia. The overall population of C. striatus demonstrated a high level of haplotype diversity (h) and a low-to-moderate level of nucleotide diversity (π). Analysis of molecular variance (AMOVA) results showed a significantly different genetic differentiation among 6 populations (F(ST)=0.37566, P=0.01). Gene flow (Nm) was high and ranged from 0.32469 to infinity (∞). No significant relationship between genetic distance and geographic distance was detected. A UPGMA tree based on the distance matrix of net interpopulation nucleotide divergence (d(A)) and haplotype network of mtDNA cyt b revealed that C. striatus is divided into 2 major clades. The neutrality and mismatch distribution tests for all populations suggested that C. striatus in the study areas had undergone population expansion. The estimated time of population expansion in the mtDNA cyt b of C. striatus populations occurred 0.72-6.19 million years ago. Genetic diversity of mtDNA cyt b and population structure among Haruan populations in Peninsular Malaysia will be useful in fisheries management for standardization for Good Agriculture Practices (GAP) in fish-farming technology, as well as providing the basis for Good Manufacturing Practices (GMP).

Matched MeSH terms: Population Dynamics
Fulltext Out of Borneo: biogeography, phylogeny and divergence date estimates of Artocarpus (Moraceae)

Williams EW, Gardner EM, Harris R, Chaveerach A, Pereira JT, Zerega NJ

Ann Bot, 2017 03 01;119(4):611-627.
PMID: 28073771 DOI: 10.1093/aob/mcw249

Background and Aims: The breadfruit genus ( Artocarpus , Moraceae) includes valuable underutilized fruit tree crops with a centre of diversity in Southeast Asia. It belongs to the monophyletic tribe Artocarpeae, whose only other members include two small neotropical genera. This study aimed to reconstruct the phylogeny, estimate divergence dates and infer ancestral ranges of Artocarpeae, especially Artocarpus , to better understand spatial and temporal evolutionary relationships and dispersal patterns in a geologically complex region.
Methods: To investigate the phylogeny and biogeography of Artocarpeae, this study used Bayesian and maximum likelihood approaches to analyze DNA sequences from six plastid and two nuclear regions from 75% of Artocarpus species, both neotropical Artocarpeae genera, and members of all other Moraceae tribes. Six fossil-based calibrations within the Moraceae family were used to infer divergence times. Ancestral areas and estimated dispersal events were also inferred.
Key Results: Artocarpeae, Artocarpus and four monophyletic Artocarpus subgenera were well supported. A late Cretaceous origin of the Artocarpeae tribe in the Americas is inferred, followed by Eocene radiation of Artocarpus in Asia, with the greatest diversification occurring during the Miocene. Borneo is reconstructed as the ancestral range of Artocarpus , with dozens of independent in situ diversification events inferred there, as well as dispersal events to other regions of Southeast Asia. Dispersal pathways of Artocarpus and its ancestors are proposed.
Conclusions: Borneo was central in the diversification of the genus Artocarpus and probably served as the centre from which species dispersed and diversified in several directions. The greatest amount of diversification is inferred to have occurred during the Miocene, when sea levels fluctuated and land connections frequently existed between Borneo, mainland Asia, Sumatra and Java. Many species found in these areas have extant overlapping ranges, suggesting that sympatric speciation may have occurred. By contrast, Artocarpus diversity east of Borneo (where many of the islands have no historical connections to the landmasses of the Sunda and Sahul shelves) is unique and probably the product of over water long-distance dispersal events and subsequent diversification in allopatry. This work represents the most comprehensive Artocarpus phylogeny and biogeography study to date and supports Borneo as an evolutionary biodiversity hotspot.

Matched MeSH terms: Population Dynamics
On the statistical study of fertility

Sundrum RM

Malay Econ Rev, 1976;21(2):36-48.
PMID: 12310921
Matched MeSH terms: Population Dynamics
On tests for sex preferences

Leung SF

J Popul Econ, 1988 Oct;1(2):95-114.
PMID: 12282511

"This paper presents a critical evaluation of three widely used tests for sex preferences: sex ratio, parity progression ratio and ordinary least squares [OLS] regression of birth interval. We show that under some appropriate conditions, the sex ratio is a valid test for sex preferences. The methods of parity progression ratio and OLS regression of birth interval fail to deal with right censoring and time varying covariates, which reduce the power of the tests. We suggest the use of hazard estimation to test for sex preferences. We demonstrate the differences among the tests by analyzing the retrospective fertility histories of the Chinese and the Malays in Malaysia. We find that unlike the two conventional methods, the hazard estimation gives clear and strong evidence of sex preferences among the Chinese in Malaysia."

Matched MeSH terms: Population Dynamics
On mobility and fertility transitions in east and southeast Asia

Skeldon R

Asian Pac Migr J, 1992;1(2):220-49.
PMID: 12343909

The relationship between fertility and mobility is examined with reference to Zelinsky's [1971] mobility transition hypothesis. Five Asian countries (Japan, South Korea, Thailand, Malaysia, China) at different stages of development and mobility transition are compared with respect to shifting sectoral patterns of migration and changing levels of fertility. National trends suggest that the development sequence proposed by Zelinsky on the basis of the European experience does not generally apply to Asia. In four out of five cases examined, fertility declined before substantial urbanization took place. Zelinsky's sequence of mobility change should be modified to fit the experience of developing countries, but the importance of the interrelations hip between fertility decline and mobility change remains

Matched MeSH terms: Population Dynamics*
On estimating fertility using first and second order births

Pathak KB, Murthy PK

Janasamkhya, 1990 Jun;8(1):73-9.
PMID: 12285535

"An attempt has been made to present two regression equations for estimating total fertility rate from the birth order data. While one of the equations has been derived from the longitudinal data of Malaysia another has been obtained from cross sectional data on Mother's total fertility rate...and births of orders one and two. These equations are used to estimate the [total fertility rate] for the districts of [Uttar Pradesh, India,] which are quite close to the estimates obtained by using other methods."

Matched MeSH terms: Population Dynamics
Offspring's labor migration and its implications for elderly parents' emotional wellbeing in Indonesia

Kumar S

Soc Sci Med, 2021 05;276:113832.
PMID: 33784552 DOI: 10.1016/j.socscimed.2021.113832

Population ageing and labor out-migration are increasingly challenging normative intergenerational support systems and familial welfare in parts of Asia. Extant studies look at how migration affects the material wellbeing of sending-households, but less is known about how migration shapes the emotional health of non-migrants as origin and destination conditions evolve. This study examines how labor migration among adult children shape the emotional health of elderly parents in Indonesia, and how observed implications are modified by alternative care arrangements and different migrant destinations. Using panel data from 2101 respondents age 50+ in the 2007 and 2014 Indonesia Family Life Survey, and individual-level fixed effects regressions, this study finds that offspring's migration is associated with increased parental depression, net of covariates. Depressive outcomes are abated if resulting care deficits are offset by co-residence or daily interactions with adult children, or if children move to economically lucrative international destinations; however, having a child in Malaysia - a destination characterized by high informal labor employment - increased parental depression. These findings draw attention to the non-economic implications of migration and the distress experienced specifically by parents who lack intergenerational support and who have concerns about child's wellbeing at destination.

Matched MeSH terms: Population Dynamics
Fulltext Nutrition and ecosystems in Sarawak: The role of the areca nut

Strickland SS, Duffield AE

Asia Pac J Clin Nutr, 1998 Dec;7(3/4):300-6.
PMID: 24393688

The effects of population pressure on agricultural sustainability in the delicate tropical and subtropical ecosystems have often been thought to explain high prevalence rates of malnutrition in rural South-East Asia. However, recent studies in rural Sarawak suggest that processes of modernisation have resulted in increased variations in energy nutritional status in adults. A contributory factor may be consumption of the areca nut (Malay pinang, of the palm Areca catechu). This is thought to influence energy balance through effects on appetite and resting metabolic rate. Body mass index (BMI, kg/m2) data for 325 Iban men and 438 non-pregnant Iban women, measured in 1990 and again in 1996, have been analysed in relation to areca use, smoking behaviour, socio-economic status, and reported morbidity. Body composition derived from skinfold thickness measurements for 313 men and 382 women was also analysed. The results suggest that use of areca nut is associated with significantly lower age-related increments in BMI and percentage body fat in women after allowing for age, smoking, reported morbidity, and confounding socio-economic factors. Therefore, the impact of recent economic and social development seen in rising prevalences of 'over-nutrition' may be modulated by use of the areca nut.

Matched MeSH terms: Population Dynamics
Novel life-history data for threatened seahorses provide insight into fishery effects

Lawson JM, Foster SJ, Lim AC, Chong VC, Vincent AC

J Fish Biol, 2015 Jan;86(1):1-15.
PMID: 25307290 DOI: 10.1111/jfb.12527

Life-history variables for three incidentally captured species of seahorse (Kellogg's seahorse Hippocampus kelloggi, the hedgehog seahorse Hippocampus spinosissimus and the three-spot seahorse Hippocampus trimaculatus) were established using specimens obtained from 33 fisheries landing sites in Peninsular Malaysia. When samples were pooled by species across the peninsula, sex ratios were not significantly different from unity, and height and mass relationships were significant for all species. For two of these species, height at physical maturity (HM ) was smaller than the height at which reproductive activity (HR ) commenced: H. spinosissimus (HM = 99·6 mm, HR = 123·2 mm) and H. trimaculatus (HM = 90·5 mm, HR = 121·8 mm). For H. kelloggi, HM could not be estimated as all individuals were physically mature, while HR = 167·4 mm. It appears that all three Hippocampus spp. were, on average, caught before reproducing; height at 50% capture (HC ) was ≥HM but ≤HR . The results from this study probe the effectiveness of assessment techniques for data-poor fisheries that rely heavily on estimates of length at maturity, especially if maturity is poorly defined. Findings also question the sustainability of H. trimaculatus catches in the south-west region of Peninsular Malaysia, where landed specimens had a notably smaller mean height (86·2 mm) and markedly skewed sex ratio (6% males) compared with samples from the south-east and north-west of the peninsula.

Matched MeSH terms: Population Dynamics
Not by science alone: why orangutan conservationists must think outside the box

Meijaard E, Wich S, Ancrenaz M, Marshall AJ

Ann N Y Acad Sci, 2012 Feb;1249:29-44.
PMID: 22175247 DOI: 10.1111/j.1749-6632.2011.06288.x

Orangutan survival is threatened by habitat loss and illegal killing. Most wild populations will disappear over the next few decades unless threats are abated. Saving orangutans is ultimately in the hands of the governments and people of Indonesia and Malaysia, which need to ensure that habitats of viable orangutan populations are protected from deforestation and well managed to ensure no hunting takes place. Companies working in orangutan habitat also have to play a much bigger role in habitat management. Although the major problems and the direct actions required to solve them-reducing forest loss and hunting-have been known for decades, orangutan populations continue to decline. Orangutan populations in Sumatra and Borneo have declined by between 2,280 and 5,250 orangutans annually over the past 25 years. As the total current population for the two species is some 60,000 animals in an area of about 90,000 km(2) , there is not much time left to make conservation efforts truly effective. Our review discusses what has and has not worked in conservation to guide future conservation efforts.

Matched MeSH terms: Population Dynamics
New world order. Overcrowded

Asiaweek, 1995 Sep 29.
PMID: 12290445
Matched MeSH terms: Population Dynamics
New approaches for estimating the demand for children

Lightbourne R

Popul Bull UN, 1987.
PMID: 12315520
Matched MeSH terms: Population Dynamics
Neonatal morbidity and mortality in Peninsular Malaysia

Abdul Kader H

Malays J Reprod Health, 1983 Dec;1(2):139-52.
PMID: 12313335
Matched MeSH terms: Population Dynamics
Muslim refugees in Southeast Asia, the Malaysian response

Dorall RF

Asian Migr, 1988 May-Jun;1(3):88-93.
PMID: 12281348

This article surveys the arrivals of Muslim refugees from countries in Southeast Asia who have not only come to Malaysia for political refuge, but who have also stayed on, in many instances integrating into the local Muslim community. The author concludes that Burmese, Thai, and Filipino Muslim refugee-cum-migrants, and the estimated 500,000 illegal Indonesian migrant workers in East and Peninsular Malaysia make the presence of economic migrants in Malaysia's towns and rural sectors a far more pressing concern to Malaysians than that posed by the arrival of genuine political refugees. Only the Indonesians present in Malaysia are consistently termed by all parties as illegal migrants and some of them have been subjected to well-publicized deportation by the Malaysian immigration authorities. Sympathy for fellow-Muslims in distress explains Malaysia's open-door policy to Muslim refugees. The Koran specifically enjoins Muslims to assist Muslim refugees who have been persecuted by others. However, the necessity to maintain regional political and military alliances, principally as a bulwark against Communism, and the Malay--Non-Malay, Muslim--Non-Muslim dichotomy in Malaysia which almost evenly divides Malaysia's 16 million population into mutually antagonistic halves, results in any overt public policy in favor of Malays and Muslims to be immediately denounced by the other half of the population as a move against the Non-Malays and Non-Muslims. Without political and media attention, the refugees live wherever they can find work, as do hundreds of thousands of mainly Indonesian illegal migrant workers. They surreptitiously get their children admitted to public schools, and through bribery, can even get Malaysian identification papers. Malaysia is a relatively tranquil haven for Malaysia's Muslim refugees compared to their homelands, but their continued stay remains dependent on the ever-present struggle for more equitable sharing of political and economic power between the different ethnic groups in Malaysia. At present, it is deemed inopportune to discuss publicly the issue of Muslim refugees in Malaysia. To do so would be to invite strong emotional responses from Malaysian Muslim groups objecting to refugee repatriation to what they see as continued persecution in Southeast Asia's non-Muslim countries, and from non-Muslim Malaysians who see in their continued presence a possible long-term demographic threat. Furthermore, the presence of Muslim evacuees granted refugee status brings painful memories as to why non-Muslim refugees principally from Indochina were denied such a similar privilege.

Matched MeSH terms: Population Dynamics
Multivariate areal analysis of the impact and efficiency of the family planning programme in peninsular Malaysia

Tan Boon Ann

Asia Pac Popul J, 1987 Jun;2(2):45-66.
PMID: 12341280
Matched MeSH terms: Population Dynamics*
Multivariate areal analyses of neo-natal mortality in peninsular Malaysia

Tey Nai Peng, Tan Boon Ann, Arshat H

Malays J Reprod Health, 1985 Jun;3(1):46-58.
PMID: 12314427
Matched MeSH terms: Population Dynamics
Multiple invasions of the Ryukyu Archipelago by Oriental frogs of the subgenus Odorrana with phylogenetic reassessment of the related subgenera of the genus Rana

Matsui M, Shimada T, Ota H, Tanaka-Ueno T

Mol Phylogenet Evol, 2005 Dec;37(3):733-42.
PMID: 15964212

The genus Rana, notably diversified in Oriental regions from China to Southeast Asia, includes a group of cascade frogs assigned to subgenera Odorrana and Eburana. Among them, R. ishikawae and the R. narina complex represent the northernmost members occurring from Taiwan to the Ryukyu Archipelago of Japan. Relationships of these frogs with the continental members, as well as the history of their invasions to islands, have been unclear. The taxonomic status of Odorrana and related genera varies among authors and no phylogenetic reassessment has been done. Using partial sequences of mitochondrial 12S and 16S rRNA genes, we estimated phylogenetic relationships among 17 species of the section Hylarana including Odorrana and Eburana, and related species from the Ryukyus, Taiwan, China, Thailand, Malaysia, and Indonesia. We estimate that (1) Odorrana is monophyletic and encompasses species of Eburana and R. hosii, which is now placed in Chalcorana, (2) the ancestor of R. ishikawae separated from other Rana in the middle to late Miocene prior to its entry to the Ryukyu Archipelago, (3) the ancestor of the R. narina complex later diversified in continental Asia, and invaded the Ryukyu Archipelago through Taiwan, (4) the R. narina complex attained its current distribution within the Ryukyus through niche segregations, and (5) vicariance of R. hosii between Malay Peninsula and Borneo occurred much later than the divergence events in the R. narina complex. Current subgeneric classification of Rana, at least of Southeast Asian members, requires full reassessment in the light of phylogenetic relationships.

Matched MeSH terms: Population Dynamics

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