Solomon Islands Populations Research Articles

Assessing Diet Quality of Indigenous Food Systems in Three Geographically Distinct Solomon Islands Sites (Melanesia, Pacific Islands).

Indigenous Solomon Islanders, like many living in Pacific Small Island Developing States (PSIDS), are currently experiencing the global syndemic—the combined threat of obesity, undernutrition, and climate change. This mixed-method study aimed to assess nutrition transitions and diet quality by comparing three geographically unique rural and urban indigenous Solomon Islands populations. Participants in rural areas sourced more energy from wild and cultivated foods; consumed a wider diversity of foods; were more likely to meet WHO recommendations of >400 g of non-starchy fruits and vegetables daily; were more physically active; and had significantly lower body fat, waist circumference, and body mass index (BMI) when compared to urban populations. Urban populations were found to have a reduced ability to self-cultivate agri-food products or collect wild foods, and therefore consumed more ultra-processed foods (classified as NOVA 4) and takeout foods, and overall had less diverse diets compared to rural populations. Clear opportunities to leverage traditional knowledge and improve the cultivation and consumption of underutilized species can assist in building more sustainable and resilient food systems while ensuring that indigenous knowledge and cultural preferences are respected.

Dietary Diversity of an Adult Solomon Islands Population.

Ongoing dietary transitions in the Solomon Islands has resulted in an over-reliance on commercially sourced foods, leading to food insecurity, and a subsequent rise in multiple forms of malnutrition. The aim of this study was to investigate the individual dietary diversity and food preferences of the adult population living in Auki, Solomon Islands. A cross-sectional study involving 133 adults was undertaken in the Auki district via an interviewer-administered questionnaire. Individual dietary diversity scores (DDS) were determined based on the results of a 24-h recall method. Overall mean DDS was 7.27 (range 2–12). Females and participants who lived outside the Auki town center had significantly higher dietary diversity scores. Low consumption of a variety of nutritious foods within food groups and high consumption of energy dense processed foods, indicates that diet quality is likely limited in some of this population. Participants desire for a diverse diet including local foods suggests that current dietary diversity status in this population may be influenced by food security rather than food preference.

Polymorphisms associated with a tropical climate and root crop diet induce susceptibility to metabolic and cardiovascular diseases in Solomon Islands.

The people of the Solomon Islands represent an Austronesian (AN)-speaking population’s adaptation to a humid tropical environment and subsistence of tuberous crops. Genome-wide association studies (GWASs) of other populations (e.g. the Human Genome Diversity Project [HGDP]) have suggested the existence of genotypes adaptive to ecoregion, diet, and subsistence, and that those genotypes are also associated with metabolic and cardiovascular diseases. Recently, the incidence of non-communicable diseases has been increasing in the Solomon Islands. In the present study, we explored the association of genotypes adaptive to a tropical environment and tuberous crop diet with metabolic and cardiovascular conditions in rural and urban AN-speaking Melanesian and Micronesian populations of the Solomon Islands. A total of 561 participants were genotyped for single nucleotide polymorphisms (SNPs) potentially associated with a tropical environment (rs174570 and rs2237892) and a tuberous crop diet (rs162036, rs185819, and rs2722425). The results showed that the allele frequencies of the Solomon Islands populations adopted patterns similar to those in populations from other hot, tropical areas with a tuberous crop diet in previous studies. Furthermore, rs162036, rs185819, rs2237892, and rs2722425 were all strongly associated with one or more metabolic and cardiovascular conditions. The derived allele of rs2722425 (i.e. rs2722425-G) was significantly associated with an elevated LDL level (P = 0.000264) even after the significance level was adjusted for multiple testing (i.e., α = 0.0005). Our results suggest that the inhabitants of the Solomon Islands exhibit the effects of the tropical environment and tuberous crop diet on their allele frequencies, and that their susceptibility to metabolic and cardiovascular diseases is therefore considered to be associated with their environment and diet.

Modernization and the onset of overweight and obesity in bougainville and solomon islands children: Cross‐sectional and longitudinal comparisons between 1966 and 1986

This set of cross-sectional and longitudinal data from children and young adults in certain Bougainville and Solomon Islands populations undergoing rapid modernization during the period 1966-1986 reveals very different responses to essentially the same stimuli-the introduction and widespread availability of western dietary items and reductions in habitual activity. Our analyses of over 2,000 children and young adults first measured in 1966-1972, with follow-up surveys in 1968-1970 and 1985-1986, show changes in overweight/obesity in these communities have their onset around puberty, and are not related to differences in childhood growth stunting. The prevalence of overweight and obesity increased substantially during the period of this study among young adults, particularly women, and in groups with more Polynesian affinities, where the frequency of overweight (BMI ≥ 25) tripled over this 20-year interval. However, the BMI of the more Papuan groups on Bougainville remained remarkably stable, even though they were close to the epicenter of modernization during this period, the Bougainville Copper Mine.

The SLC2A9 nonsynonymous Arg265His variant and gout: evidence for a population-specific effect on severity

IntroductionThe C allele of the nonsynonymous Arg265His (rs3733591) variant of SLC2A9 confers risk for gout in Han Chinese, Solomon Island and Japanese samples, with a stronger role in tophaceous gout. There is no evidence for an association with gout in Caucasian populations. In the present study, we tested rs3733591 for association with gout in New Zealand (NZ) Māori, Pacific Island and Caucasian samples.MethodsRs3733591 was genotyped across gout patients (n = 229, 232 and 327 NZ Māori, Pacific Island and Caucasian samples, respectively) and non-gout controls (n = 343, 174 and 638 Māori, Pacific Island and Caucasian samples, respectively). Further Caucasian sample sets consisting of 67 cases and 4,712 controls as well as 153 cases and 6,969 controls were obtained from the Framingham Heart Study and the Atherosclerosis Risk in Communities study, respectively. The Polynesian samples were analyzed according to Eastern and Western Polynesian ancestry.ResultsNo evidence for risk conferred by the C allele of rs3733591 with gout was found in the sample sets of NZ Māori (odd ratio (OR) = 0.98, P = 0.86), Eastern Polynesians (OR = 0.99, P = 0.92), Western Polynesians (OR = 1.16, P = 0.36) or combined Caucasians (OR = 1.15, P = 0.13). The C allele was significantly overrepresented in Māori tophaceous cases compared to cases without tophi (OR = 2.21, P = 0.008), but not in the other ancestral groupings.ConclusionsNoting that our study's power was limited for detecting weak genetic effects, we were unable to replicate associations of rs3733591 with gout in Eastern Polynesian, Western Polynesian and Caucasian samples. However, consistent with a previous study of Han Chinese and Solomon Island populations, our data suggest that rs3733591 could be a marker of severe gout in some populations. Our results also suggest that the effect of this variant is population-specific, further confirming population heterogeneity regarding the association of SLC2A9 with gout.

Molecular phylogenetics and diversification within one of the most geographically variable bird species complexesPachycephala pectoralis/melanura

The golden‐mangrove whistler complexPachycephala pectoralis/melanurais, with 66 named populations, described as the most complex avian example of geographic variation in the World. It represents a well‐known example of niche differentiation where one speciesP. pectoralisis found on faunistically rich larger islands (and mainland) and the otherP. melanurais confined to adjacent, faunistically poor islets. Except for a comparison of some Solomon Island populations, the relationships among these taxa have not been tested using molecular data. Here we combine a dense taxon sampling (22 populations of 12 named taxa distributed east of New Guinea and in Australia), with molecular data (two nuclear and two mitochondrial markers) to unravel more of the evolutionary history behind the golden whistler complex. In particular we examine relationships betweenPachycephala melanura, and the very similar‐lookingP. citreogaster(Bismarcks Islands) andP. pectoralis(Australia). We demonstrate that a well‐supported group of golden whistlers inhabit the Bismarck Islands and that several small islets in the immediate vicinity are inhabited by another monophyletic group consisting ofP. melanura, mangrove golden whistler.

Evolutionary Lineages in Emballonura and Mosia Bats (Mammalia: Microchiroptera) from the Southwestern Pacific1

The microchiropteran bat family Emballonuridae is widely distributed in archipelagos of the southwestern Pacific, with especially strong representation of genera Emballonura and Mosia. DNA sequences from three segments of the mitochondrial genome were collected from four species of Emballonura and from M. nigrescens to investigate the relationship of genetic differentiation to archipelago biogeography. Specimens of each species formed monophyletic clades in maximum parsimony and Bayesian analyses. Mosia nigrescens was genetically distant to the other four species. The other four studied species formed a monophyletic clade composed of the pairs E. beccarii, E. serii and E. raffrayana, E. semicaudata. Clades within species were strongly concordant with geography, with only two counterexamples (E. semicaudata in Fiji and E. raffrayana in the Solomon Islands) to the general finding that each island's population of a species constitutes a monophyletic clade. Genetic results do not agree with current subspecific designations within M. nigrescens. Samples from Woodlark, Alcester, and Manus Islands are phylogenetically closer to Papuan mainland samples than to Solomon Islands and New Ireland samples supposedly belonging to the same subspecies. Results suggest that Emballonura can establish populations across wide water barriers but does so infrequently. The isolating effect of water barriers is exemplified by the substantial genetic distinctiveness of Solomon Islands and New Ireland populations of both E. raffrayana and M. nigrescens. Absence from New Britain of E. beccarii, E. raffrayana, and E. serii (all known from New Ireland) may also reflect effects of water barriers if not due to collecting artifacts.

Allelic diversity in the merozoite surface protein 1 gene of Plasmodium falciparum on Palawan Island, the Philippines

Allelic diversity of the Plasmodium falciparum merozoite surface protein 1 gene ( msp1) is mainly generated by meiotic recombination at the mosquito stage. We investigated recombination-based allelic diversity of msp1 in a P. falciparum population from Palawan Island, the Philippines, where malaria transmission is moderate. We identified the 5′ recombinant types, 3′ sequence types and msp1 haplotypes (unique combinations of 5′ recombinant type and 3′ sequence type), and compared them with those of P. falciparum from the Solomon Islands, where malaria transmission is high. The mean number of 5′ recombinant types per patient in Palawan was 1.44, which is comparable to the number for the Solomon Islands (1.41). The Palawan parasite population had 15 msp1 haplotypes, whereas the Solomon Islands population had only 8 haplotypes. The Palawan population showed strong linkage disequilibrium between polymorphic blocks/sites within msp1, which is comparable to the results for the Solomon Islands. These findings support our hypothesis that the extent of allelic diversity of msp1 is determined not only by the transmission intensity but also by the number of msp1 alleles prevalent in the local parasite population and the extent of mixed-allele infections. Contribution of a high prevalence of the chloroquine (CQ)-sensitive allele of P. falciparum CQ resistance transporter ( pfcrt) to the relatively high msp1 diversity in the Palawan population is discussed.

Y‐chromosome diversity is inversely associated with language affiliation in paired Austronesian‐ and Papuan‐speaking communities from Solomon Islands

The Solomon Islands lie in the center of Island Melanesia, bordered to the north by the Bismarck Archipelago and to the south by Vanuatu. The nation's half-million inhabitants speak around 70 languages from two unrelated language groups: Austronesian, a language family widespread in the Pacific and closely related to languages spoken in Island Southeast Asia, and "East Papuan", generally defined as non-Austronesian and distantly related to the extremely diverse Papuan languages of New Guinea. Despite the archipelago's presumed role as a staging post for the settlement of Remote Oceania, genetic research on Solomon Island populations is sparse. We collected paired samples from two regions that have populations speaking Austronesian and Papuan languages, respectively. Here we present Y-chromosome data from these samples, the first from Solomon Islands. We detected five Y-chromosome lineages: M-M106, O-M175, K-M9*, K-M230, and the extremely rare clade, K1-M177. Y-chromosome lineages from Solomon Islands fall within the range of other Island Melanesian populations but display markedly lower haplogroup diversity. From a broad Indo-Pacific perspective, Y-chromosome lineages show partial association with the distribution of language groups: O-M175 is associated spatially with Austronesian-speaking areas, whereas M-M106 broadly correlates with the distribution of Papuan languages. However, no relationship between Y-chromosome lineages and language affiliation was observed on a small scale within Solomon Islands. This pattern may result from a sampling strategy that targeted small communities, where individual Y-chromosome lineages can be fixed or swept to extinction by genetic drift or favored paternal exogamy.

Restricted gene flow between Holothuria scabra (Echinodermata: Holothuroidea) populations along the north-east coast of Australia and the Solomon Islands

To describe patterns of gene flow for the fished holothurian species Holothuria scabra 17 to 141 individuals were collected from 8 populations from north-east Australia, the Torres Strait, and the Solomon Islands. Samples were investigated by allozyme electrophoresis of 7 polymorphic loci. Cluster analyses using Rogers' genetic distance identified 3 distinct groups of populations from the north-east coast of Australia, representing samples from the 3 regions Hervey Bay, Upstart Bay and Torres Strait. Populations in the latter region were closely connected to those from the Solomon Islands. F-statistics indicated restrictions in gene flow (average genetic variation between popula- tions, FST = 0.088). Hierarchical analyses revealed that 94.7% of the variation was within sampling locations. Approximately 77% of the variance among populations was due to differences between regions, and 23% within regions (most of the latter caused by differences between the 2 Solomon Island populations). Mantel's tests indicated that a high proportion of the variation in genetic dis- tances along the north-east coast of Australia was explained by isolation by distance (Mantel's nor- malised Z = 0.88). This proportion reduced when the Solomon Islands were included (Z = 0.65). The detection of separate stocks along the north-east coast of Australia is an important finding that has significant consequences for the development of sustainable management plans for this species. Low dispersal may significantly reduce recovery of overfished areas if no local refugia are provided.

Changes in the composition of the auditory bulla in southern Solomon Islands populations of the grey cuscus, Phalanger orientalis breviceps (Marsupialia, Phalangeridae)

The auditory bulla is a much-scrutinized taxonomic character of mammals, which is generally regarded as showing a high degree of structural consistency within higher taxa. Observations of bulla variability in populations of the marsupial Phalanger orientalis from the Solomon Islands demonstrate considerable flexibility in bulla makeup, with variable incorporation of the squamosal into the tympanic floor. Studies of the ontogeny of the bulla in Phalanger show the presence of three ossification centres, including an entotympanic. Squamosal invasion of one of these ossificiation centres is seen as a possible result of inbreeding, arising from the mode of colonization of the Solomon Islands by this species. This suggests that, under certain conditions, considerable morphological plasticity may be induced within the selective constraints of bulla function.

Changes in the composition of the auditory bulla in southern Solomon Islands populations of the grey cuscus, Phalanger orientalis breviceps (Marsupialia, Phalangeridae)

The auditory bulla is a much-scrutinized taxonomic character of mammals, which is generally regarded as showing a high degree of structural consistency within higher taxa. Observations of bulla variability in populations of the marsupial Phalanger orientalis from the Solomon Islands demonstrate considerable flexibility in bulla makeup, with variable incorporation of the squamosal into the tympanic floor. Studies of the ontogeny of the bulla in Phalanger show the presence of three ossification centres, including an entotympanic. Squamosal invasion of one of these ossificiation centres is seen as a possible result of inbreeding, arising from the mode of colonization of the Solomon Islands by this species. This suggests that, under certain conditions, considerable morphological plasticity may be induced within the selective constraints of bulla function.

Smoking and pulmonary function in five Solomon Island populations.

The relationship between smoking and lung function was examined in a large sample of healthy Solomon Island Melanesians and Polynesians as part of a multidisciplinary study carried out in 1985 and 1986. Comparisons are made between samples of smokers and non-smokers to determine if smoking is associated with a reduction in pulmonary function among males and females between 25 and 75 years of age. The results of this study indicate that cigarette smoking causes significant reductions in the pulmonary function of these populations. In addition, a clear difference in pulmonary function between males and females, as well as a general reduction in female FEV1 values, suggests that cooking smoke inhalation may be operating as a possible risk factor to the pulmonary health of women. Further research is needed to quantify exposure to smoke of both males and females and relate this measure to declines in pulmonary function.

Prevalence of abnormal glucose tolerance in six Solomon Islands populations

A survey of blood glucose levels in six Solomon Islands populations may support the hypothesis that susceptibility to diabetes is almost absent among non-Austronesian-speaking Melanesians regardless of their level of modernization. Among Austronesian-speaking Melanesians, however, diabetes is emerging. Differences in prevalence rates of diabetes between Austronesians and non-Austronesian speakers in this survey are significant (P less than .0001).

Prevalence of antibodies interactive with HTLV‐I antigens in selected Solomon Islands population

Serum samples obtained in 1986 from healthy individuals in three distinct Solomon Islands populations were screened for antibodies to human lymphotropic virus type I (HTLV-I). One of the populations tested lives on the remote Polynesian outlier atoll, Ontong Java. The other two groups, the Baegu and the Lau, are Melanesians living on Malaita, the most populous of the larger Solomon Islands. Eighty-eight of a total of 601 (14.6%) sera tested were repeatably reactive in an enzyme-linked immunosorbent assay (ELISA) that uses as antigen a lysate of HTLV-I viral particles. The prevalence of antibodies interactive with HTLV-I viral particles. The prevalence of antibodies interactive with HTLV-I antigens varied among the three groups, ranging from 8.5% (16/188) in the Baegu, through 13% (7/54) in the Lau, to 18.1% (65/359) among the Ontong Java population. The specificity of the screening ELISA was confirmed by protein immunoblot. No serum samples were obtained from children under 9 years of age. Although 121 of the 601 sera came from children between the ages of 9 and 19, none of these were reactive in the HTLV-I ELISA. Starting in the third decade, the prevalence of HTLV-I seropositivity increased with age, from 8.8% (10/113) between the ages of 20 and 29 to a peak of 25.9% (15/58) and 25% (15/60) in the sixth and seventh decade, respectively. This age-specific prevalence pattern is strikingly similar to that which is seen in populations where HTLV-I infection is endemic.

Some genetic traits in Solomon Island populations. II. Hand clasping, arm folding, and handedness.

AbstractAmong 1,438 persons in four Solomon Island populations, handclasp showed no age, sex, or tribal differences. The percentage of R‐claspers (right thumb on top), 66.4, exceeded those previously reported for Caucasian and Mongoloid peoples and resembled those for Oceanic and African samples. Handclasp was associated with handedness but not with armfold; it showed no assortative mating and no simple form of inheritance. Armfold showed an age association (more R‐folders among the youngest children), but none with sex or tribe, no assortative mating, and no pattern of inheritance. Its frequency, 41.4%, resembled those of populations around the world. Left handedness, 2.8% over all four tribes, paralleled contact with Western culture.

Some genetic traits in Solomon Island populations. IV. Mid-phalangeal hair.

AbstractAmong 425 Lau and 467 Baegu of northern Malaita, there were no tribal differences in mid‐phalangeal hair. The trait was present more often in males than in females, and after puberty than before it. Age differences were more marked for males than for females. Among 168 men 20 years of age and older in both tribes, the frequency of mid‐phalangeal hair was 58.3%; among 189 women of similar age, 34.4%. These frequencies were at or just below those reported for Caucasian samples, just above that for Japanese, and considerably above those for Negroes and American Indians. Analysis of family data did not confirm the hypothesis that the absence of mid‐phalangeal hair is recessive to its presence.

Some genetic traits in Solomon Island populations. Concluding remarks.

Some genetic traits in Solomon Island populations. Concluding remarks.

Some genetic traits in Solomon Island populations. 3. Relative toe length.

AbstractAmong 1,605 Solomon Islanders from four tribes, there was no sex difference in relative length of the first and second toes. In three of the tribes, longer first toes were slightly more frequent in persons over the age of 45. The percentages of longer first toes in the groups as a whole were 60.5% for Baegu, 66.4% for Nasioi, and 72.1% for Kwaio. These frequencies, resembling those reported for white Americans, Europeans, and single small samples of New Caledonians and Vietnamese, were much below those for Africans. The fourth tribe, the Lau, had only 37.1% with a longer first toe, the lowest percentage reproted so far around the world. No simple mode of single‐gene inheritance was apparent, and polygenic inheritance is proposed.

Some genetic traits in Solomon island populations. I. Introduction: people and habitats.

AbstractTo introduce a set of genetic studies among Solomon Islanders, four tribal groups on Bougainville and Malaita Islands are described. They were observed in 1966 and 1968 by social anthropologists and biomedical scientists from Harvard University. The groups varied in habitat and way of life from fishermen living on artificial islets in a saltwater lagoon (the Lau, on Malaita) to shifting agriculturists (the Nasioi, on Bougainville, and the Kwaio and Baegu, on Malaita). The Nasioi were darker than the Malaitans and spoke a non‐Austronesian rather than a Melanesian language; they were also more Westernized. Coverage of residents in designated hamlets ranged from 78% to over 95%. In all, 1,626 persons were studied: 256 Nasioi, 443 Kwaio, 442 Lau, and 485 Baegu. Genetic differences have been found between the Nasioi and the Malaitans, and between the Lau and the other Malaitans.