Growth status of school-age Mayan children in Belize,Central America

This paper reports the growth status of a sample of Mopan Maya school children living in a rural village in Belize. These children exhibit a growth pattern typical of chronic undernutrition, in that a high percentage are stunted (66%), but virtually none are wasted by WHO criteria. The Belize Maya children are compared to four other Amerindian groups and found to be shorter and lighter than a semi-urban group from Guatemala, but taller and heavier than three rural groups from Guatemala and Mexico. The Belize children exhibit the largest arm circumferences among all five groups. This pattern of growth is discussed in light of current ideas concerning the contribution of genetics vs. environment to childhood growth and population wellbeing. © 1994 Wiley-Liss, Inc.     

Reproductive dynamics of a tropical freshwater crocodilian: Morelet's crocodile in northern Belize

Morelet's crocodile Crocodylus moreletii has not been well-studied and many aspects of its life history are unknown. In particular there is a notable paucity of information on nesting and reproductive ecology. We studied the nesting ecology of Morelet's crocodile in northern Belize from 1992 through 1995. Nesting occurs at the onset of the wet season in mid-June and continues through mid-July (mean oviposition date =1 July±10 days). Eggs hatch from mid-August through mid- to late September. Nesting effort at our primary study site remained relatively constant during 1992, 1993 and 1995, but nearly doubled in 1994; this appeared to reflect a regional trend. Natural and man-made islands are heavily used as nesting sites. Nesting success in 1993 and 1994 was consistently higher on natural islands when compared with man-made islands or shoreline sites. Nest losses were primarily due to flooding and raccoon Procyon lotor predation. Losses from predation were greatest in 1994 when unseasonably low water levels facilitated predator access to nests. Females probably reach sexual maturity in 7–8 years after attaining a total length of 150 cm. Mean clutch size (25.0±7.6; range=9–42; n =73) did not differ among years. Mean clutch size, egg width (EW), egg length, egg mass (EM) and clutch mass were positively correlated with female snout–vent length (SVL). Mean EW was the best predictor of female SVL. A partial correlation analysis of egg and clutch attributes found that independent of female SVL, EM increases with increasing clutch size.     

Patterns of growth and malnutrition among preschoolers in Belize

An anthropometric survey of 750 preschoolers was conducted during 1979 in Belize to assess nutritional status in two districts, one coastal and the other inland. Mothers were interviewed concerning reproductive history, child's health and dietary history, and associated factors. Analysis included the recognition of low arm circumference, weight-for-age, stature-for-age, and weight-for-stature. Survey results indicate that about 25% of the children, birth to 5 years old, show evidence of stunting, while 2.5% show evidence of wasting. Comparisons of rates of malnutrition by ethnic group reveal that the Maya and Garifuna (Black Carib) children are significantly more commonly malnourished than others. Applying a discriminant function to groups of children designated as “poor” and “better-than-average” growth classes reveals several factors which may be contributory to the etiology of preschool malnutrition in Belize. The frequency of diarrhea and age at introduction to solid foods, are significantly related to growth retardation among preschoolers. Analysis of 24-hour-diet recalls corroborates the patterning of malnutrition among ethnic groups.     

Pleistocene facies of Belize barrier and atoll reefs

The knowledge of Pleistocene reef facies of Belize, Central America, is largely limited to outcrops in the northernmost part of the country. Otherwise, Pleistocene limestone, which forms the basement of the modern barrier and atoll reefs, occurs in the subsurface and is to a major extent unstudied. Based on the study of 40 m of core from 25 rotary core holes collected on central and southern Belize barrier and on atoll reefs, five Pleistocene reef facies are distinguished in the present study. They include (1) Acropora palmata grainstone, (2) Acropora cervicornis grainstone, (3) biogenic grainstone, (4) mollusk packstone, and (5) mollusk-foram wackestone. Facies 1 and 3 occur on marginal reefs, facies 2 is found on marginal and lagoonal reefs, and facies 4 and 5 mark lagoon shoals and lagoons, respectively. Most of the facies have equivalents in the Pleistocene of the wider Caribbean and also in the modern of the study area. Diagenetic features include dissolution, caliche formation, laminated blocky low-magnesium-calcite and dogtooth spars. Age data from Pleistocene corals obtained during earlier studies are discussed, and indicate deposition during marine isotope stage 5, between 140–80 ka bp.     

DDTs in Soils Affected by Mosquito Fumigation in Belize

DDTs were sprayed extensively in Belize to combat malaria but widespread use ceased after 1997. To determine if DDTs still persist in Belize's soils, 23 composite soil samples were collected from each of the two towns of Dangriga and Punta Gorda. Dichlorodiphenyltricholoroethane (DDT) and its breakdown products dichlorodiphenyldichloroethylene (DDE) and dichlorodiphenyldichloroethane (DDD) were the only organochlorine compounds detected in the soils. Results show that DDTs are transferred to the soil environment as a result of spraying houses and that the pesticides still persist in soils in southern Belize after more than 10 years of non-use. Sprayed lots had DDT concentrations up to 240 μg/kg in Dangriga and up to 410 μg/kg in Punta Gorda. All unsprayed lots had below detection limit concentrations, with the exception of two sites in Punta Gorda. Hot spot analysis in GIS indicates that significant spatial variability exists in detected concentrations of DDTs, which has implications for extrapolation of local data. Belize currently has no guidelines for determining risk of DDTs to human health and soil cleanup, but soil cleanup guidelines employed by foreign governmental entities such as the Netherlands and California show that all detected pesticide concentrations in this study are below mandated concentrations of concern for the residential areas of these regions. However, since exposure scenarios may be different in Belize, it is recommended that the Belize Ministry of Health conducts a risk analysis to ascertain if the concentrations of DDTs in sprayed areas pose a risk to the inhabitants of the two towns.     

Skin colorimetry in Belize. I. Conversion formulae

Comparisons between skin colorimetry reports have been hampered by the common use of two different types of portable reflectometers, which sample reflectances at different wavelengths. In an attempt to provide direct comparability between the two machines, multiple linear regression equations were derived from reflectance spectrophotometry readings on 308 Black Caribs and 175 Creoles in Belize, Central America, using both machines. Cross validation tests show the coefficients presented are applicable to independent data sets and generally applicable to other heavily pigmented populations. Comparisons with previously published conversion formulae, which were from very small samples using simple linear regression, show a definite improvement in predictive accuracy when using multiple regression equations based on a large sample.     

生态绿地空间与城乡人居环境规划

从分析我国城市绿地系统规划工作中的现有理论问题出发,提出了新的“生态绿地空间”规划概念,论述了生态绿地空间在人居环境中的定位,我国城乡生态绿地空间的现状和危机,城镇密集地区生态绿地空间的保护和发展等问题。     

The impacts of tourism on coral reef conservation awareness and support in coastal communities in Belize

Marine recreational tourism is one of a number of threats to the Belize Barrier Reef but, conversely, represents both a motivation and source of resources for its conservation. The growth of tourism in Belize has resulted in the fact that many coastal communities are in varying stages of a socio-economic shift from dependence on fishing to dependence on tourism. In a nation becoming increasingly dependent on the health of its coral reef ecosystems for economic prosperity, a shift from extractive uses to their preservation is both necessary and logical. Through examining local perception data in five coastal communities in Belize, each attracting different levels of coral reef related tourism, this analysis is intended to explore the relationship between tourism development and local coral reef conservation awareness and support. The results of the analysis show a positive correlation between tourism development and coral reef conservation awareness and support in the study communities. The results also show a positive correlation between tourism development and local perceptions of quality of life, a trend that is most likely the source of the observed relationship between tourism and conservation. The study concludes that, because the observed relationship may be dependent on continued benefits from tourism as opposed to a perceived crisis in coral reef health, Belize must pay close attention to tourism impacts in the future. Failure to do this could result in a destructive feedback loop that would contribute to the degradation of the reef and, ultimately, Belize’s diminished competitiveness in the ecotourism market.

Neighbor Trees: Shade, Intercropping, and Cacao in Ecuador

Previous studies have shown that shade trees in cacao and coffee are important habitats for inter-American migratory birds. A survey of 21 cacao farmers along the northern, central, and southern Pacific Coast of Ecuador found that shade trees are associated with unirrigated, traditional cacao varieties and low levels of chemical inputs. Farmers stressed the importance of shade for managing soil moisture and soil fertility, and for managing some weeds and diseases. Most of the shade trees were not wild forest trees, but had been planted and protected by the farm families. Many other trees are intercropped with cacao for economic reasons, not related to shade. Chocolate manufacturers, consumers, and environmental activists can encourage farmers to maintain shade canopies by paying a premium for the traditional, shade-loving, high-quality aromatic cocoa varieties.     

Skin colorimetry in Belize. II. Inter- and intra-population variation

Skin colorimetry readings taken in Belize, Central America (formerly British Honduras) with the two most commonly used portable reflectometers reveal significant differences in mean reflectance between Garifuna (Black Caribs) and Creoles, and between Garifuna in two settlements. These differences are related to variation in African, Indian, and European admixture, as estimated from serological markers. Sex differences are not evident in univariate comparisons, but females are significantly lighter than males in multivariate analyses of variance. Polynomial age trends exist in some groups for certain variables, but account for a very small amount of the variation in skin color within these groups.     

Sacred Giants: Depiction of Bombacoideae on Maya Ceramics in Mexico,Guatemala, and Belize

Sacred Giants: Depiction of the Malvaceae Subfamily Bombacoideae on Maya Ceramics in Mexico, Guatemala, and Belize This study categorized and identified plants depicted on Maya ceramics from the Classic Period (250 a.d.–900 a.d.). We chose art objects with a predominance of iconographic images of Malvaceae subfamily Bombacoideae, which are easily identified morphologically and have culinary, medicinal, ceremonial, economic, and cosmological significance to the Maya. Among ten species of Bombacoideae native to the Southern Lowlands region of Central America (Belize, parts of Guatemala, and Mexico), the Maya utilized at least six, which also have Maya names. We observed four or five bombacoid species depicted on Maya ceramics; most images were identifiable to genus. Burial urns and incensarios (incense burners) commonly had images of trunk spines of Ceiba pentandra, the Maya “World Tree.” Flowers of Pseudobombax ellipticum, a plant used to make ceremonial beverages, were most similar to floral images portrayed on vessels, bowls, and plates, although the morphologically similar flowers of Pachira aquatica may also be depicted. Plants representing Quararibea funebris or Q. guatemalteca, which were used during preparation of cacao beverages, were discernable on drinking vessels.     

The Human Behavioral Ecology of Contemporary World Issues

Human behavioral ecology (HBE) began as an attempt to explain human economic, reproductive, and social behavior using neodarwinian theory in concert with theory from ecology and economics, and ethnographic methods. HBE has addressed subsistence decision-making, cooperation, life history trade-offs, parental investment, mate choice, and marriage strategies among hunter-gatherers, herders, peasants, and wage earners in rural and urban settings throughout the world. Despite our rich insights into human behavior, HBE has very rarely been used as a tool to help the people with whom we work. This article introduces a special issue of Human Nature which explores the application of HBE to significant world issues through the design and critique of public policy and international development projects. The articles by Tucker, Shenk, Leonetti et al., and Neil were presented at the 104th annual meeting of the American Anthropological Association (AAA) in Washington, D.C., in December 2005, in the first organized session of the nascent Evolutionary Anthropology Section (EAS). We conclude this introduction by summarizing some theoretical challenges to applying HBE, and ways in which evolutionary anthropologists can contribute to solving tough world issues.

Effect of Crinipellis perniciosa Infection on Abscission of Cacao Cotyledons, Reserve Mobilization and Dry Matter Partitioning

Infection by Crinipellis perniciosa on cacao seedlings prevented the abscission of cotyledons which normally abscise within 32–61 days from seed sowing. The early growth and development of control and artificially inoculated seedlings was investigated for root dry mass (RDM), shoot dry mass (SDM), shoot‐to‐root ratio (SRR), total dry mass (TDM), cotyledonary dry mass (CDM) and cotyledonary water content (CWC). Cotyledonary reserve mobilization was estimated at 69 and 56% at 5 weeks and 79 and 64% at 8 weeks in control and infected seedlings, respectively. Infection induced the enlargement of tissues but was not accompanied by an increase in dry mass. Infection both delayed and reduced the utilization of cotyledonary food reserves resulting in slower accumulation of RDM, SDM and TDM culminating in a reduction of growth by a factor of 1.6 at 8 weeks. However, the SRR of inoculated plants was similar to that of control plants, suggesting that the balance between the root and shoot systems exists which is unchanged by the effect of the pathogen. CWC was decreased upon senescence to an average of 65% at abscission. The prevention of cotyledonary abscission in infected seedlings is suggested to be due in part to the CDM remaining above a critical level of 20% of the initial CDM. The implication of this response in relation to the infection biology of the pathogen is discussed.     

Longitudinal analysis of adolescent growth of ladino and Mayan school children in Guatemala: effects of environment and sex.

The rate of growth in height and the timing of adolescent growth events are analyzed for two samples of Guatemalan children. One sample includes Mayan school children, 33 boys and 12 girls between the ages of 5.00 to 17.99 years, living under poor conditions for growth and development. The second sample includes ladino children, 78 boys and 85 girls of the same age range, living under favorable conditions for growth. The Preece-Baines model I function is used to estimate mean values for rates and timing of childhood and adolescent growth events for the two groups. Significant statistical contrasts (t-tests) of these means show Mayan boys reach the age of "take-off" (TO; the onset of the adolescent growth spurt) 1.45 years later, achieve peak height velocity (PHV) 1.68 years later, and continue growing for about 2.0 years longer than do the ladino boys. Despite the Mayan boys' increased duration for growth they grow significantly more slowly than the ladinos. Mayan boys are 6.60 cm shorter than ladinos at the age of TO and are estimated to be 7.71 cm shorter than the ladinos at adulthood. Mayan girls reach the age of TO 0.93 years later than do the ladina girls, but the two groups do not differ in the age at PHV or the age at adulthood. The mean height of Mayan girls is significantly less than that of ladinas at the age of TO (6.5 cm), and this difference increases to an estimated 11.14 cm at adulthood. Possible causes of these ethnic and sex-related differences in amounts and rates of growth are discussed in relation to hypotheses about the genetic and environmental determinants of human development.     

土壤生态学研究趋势

以土壤生物为中心,研究土壤生物间以及土壤生物和土壤非生命环境间相互作用,揭示土壤生物群落的结构和功能,进而从生态学的角度认识土壤生态系统的动态性和整体性,优化其结构和功能,是土壤生态学基本的     

Germination strategies of palms: the case of Schippia concolor Burret in Belize

A review on seed germination and early seedling development in the palms (Palmae) is presented and variation in the germination process of palm seeds discussed. The three major types of palm seed germination are reviewed, and a new, undescribed mechanism of germination found inSchippia concolor Burret in Belize is described. Possible reasons for this variant pattern are considered, and the ecological and evolutionary significance of different germination types and their variants is discussed.     

Oxidative Stress during Development of Alcoholic Fatty Liver: Therapeutic Potential of Cacao Polyphenol

The lipid and antioxidative/oxidative profiles of livers from rats fed an ethanol liquid diet for 8 weeks provided evidence for an involvement of oxidative stress (e.g., phospholipid peroxidation) in the development of alcoholic fatty liver (AFL), possibly in an early stage. Cacao polyphenol supplementation produced an ameliorating effect, and may help in AFL prevention.     

Studying Cultural Evolution at the Tips: Human Cross-cultural Ecology

While human genetic variation is limited due to a bottleneck on the origin of the species ～200 kya, cultural traits can change more rapidly, and may do so in response to the variation in human habitats. Does cultural diversification simulate a natural experiment in evolution much like biodiversity so that cultural divergences and convergences can be interpreted in terms of the differences and similarities of local environments? Or is cultural diversity simply the result of human behavioral flexibility? Although the majority of cultural data comes from the tips of the hominin phylogeny, anthropologists can follow the example of evolutionary ecologists, who often compare the endpoints of phylogenies when that is all that is available. This article compares 97 contemporary indigenous language communities from around the world, and 24 of their cultural traditions, to help determine whether human cultures and their cultural traits are proportionately dispersed, as predicted by the neutral theory of biodiversity, or whether they show non-proportionalities that could be explained with evolutionary reasoning.     

Effects of Selection Logging on Birds in Northern Belize1

We compared bird diversity and frequency in selection logged and unlogged forest to determine the effects of recent selection logging on avian biodiversity in a subtropical, moist evergreen forest. We used a combination of mist netting and fixed-radius point counts to assess bird communities in February and March 1993 in northwestern Belize. Vegetation structure and composition was similar in logged and unlogged forest. The 66 most common species occurred with statistically similar frequency in logged and unlogged forest although 13 species were two times more frequent in intact forest. Numbers of total bird species were similar between logging gaps and the logged forest matrix, and between the logged forest matrix and unlogged forests. A comparison of numbers of species in 26 guilds based on migration strategy, diet, foraging substrate, and height strata also showed them to be similar regardless of logging history. Our results differed from previous studies that reported lower bird species richness and abundance of individual species in logged tropical forests than in unlogged forest. The differences might be explained by the lower logging intensity and/or greater levels of natural disturbance in our study area compared to previous studies.     

Recruitment of Black Howler Fruit Trees in Fragmented Forests of Northern Belize

We examined recruitment of trees whose seeds are dispersed by black howler monkeys (Alouatta pigra) in forest fragments within the Community Baboon Sanctuary in north-central Belize. In the fragments, most other large frugivores are absent and howlers dominate the large frugivore community. Consequently, we expected to observe an increased representation of howler fruit trees among the sapling community. To test this prediction preliminarily we observed howler feeding behavior for one year and conducted adult tree and sapling transects in 6 locations where howlers were present. We sampled a seventh site where howlers were absent for vegetation only. We found that in 4 of 6 sites there were proportionately fewer howler fruit saplings when compared to adult tree samples. However, when recruitment of howler fruit trees in the 6 sites was compared to a site where howlers were absent, 11 of 12 species had relatively higher recruitment. The lack of recruitment among howler fruit trees in general likely reflects differences in responses of individual species, as well as disruptions from human activities to natural processes within the forests. The observed lower recruitment patterns of howler trees suggest that over time, the abundance of the trees will likely decline and thus affect the foraging behavior and possibly survival of howlers in the fragmented forests.