Living conditions and growth of maya indian and non-maya boys from yucatan in 1993 in comparison with other studies

The purpose of this study was to characterize the biological status and living conditions of boys inhabiting the northern part of Merida. Studies were conduoted in summer 1993, in several secondary schools in the northern part of the Merida, capitol of Yucatan, Mexico. The material consisted of biological measurements of 497 boys aged from 12 to 17 years. Also parents of these children were interviewed. Mothers (497) aged from 28 to 60 years (40 on the average) and fathers (495) aged from 30 to 62 years. Values of biological characteristics were calculated for the whole material, and also separately for the families in which both parents were Maya Indians, Non-Mayas and mixed. The differences between Mixed and Non-Mayas were distinct in stature, trunk length, upper extremity length, head length, head circumference, hips breadth index, cephalic and frontal indices, thus, mainly in body size and the head and face form. Differences between Mayas and Non-Mayas were distinct in the most measures: direct measurements ofbody weight and height, trunk and both extremities length, shoulder breadth, head length, face and nose breadth, head, waist and hips circumferences (which did not show differences between two other groups as a direct measure) and triceps skinfold thickness. The differences were also found in some indices (cephalic, frontal and face) and this probably has a non-adaptive character. The difFerences in other body proportions, which could be rather easy adjustable in the meaning on ontogenetic development were not found. The constitutional differences were observed in stature, arm fatfold and hip breadth. Body proportions were under the strong influence of living conditions and this probably caused the lack of difFerences between 3 ethnic groups. The contemporary Maya boys in comparison with the Steggerda data (1941) were on average 10 cm taller, more plumb by 10 units of BMI, and had more rounded heads. Head, which is under a strong genetic control and has more conservative character showed differences between Maya and Mixed groups versus Non-Mayas.     

Migration,socio-economic status and age at menarche and age at menopause in the Yucatan,Mexico

The possible effects of migration and socio-economic status (SES) on age at menarche (MENA), age at menopause (MENO), potential reproductive period (PRP), and the correlation between MENA and MENO, were studied in 216 women in the Yucatan, Mexico. They were divided into three groups: migrant from the sisal-growing area on the coast, and sisal and coastal sedentary. Coastal sedentary women, living in the best socio-economic conditions, have the youngest MENA and the oldest MENO. Early migrant women have a significantly younger MENO (p.<0.05) and shorter PRP than Coastal sedentary women. There was no evidence of selective migration for MENA. When the Migrant, Sisal and Coastal sample were divided into cohorts by SES, it was impossible to obtain any clear picture. MENA increases with increased SES for the Coastal and Sisal cohorts, while the Migrant cohorts show an opposite trend. However, only the Low/Middle and High/Middle cohort differences for the Coastal sample are significant (p.<0.05, in both cases). It seems that migration has a limited affect on MENO and the PRP. Contrary to reports in the literature, the correlations between MENA and MENO and migrant status, and migrant socio-economic statuses, are negative, although these correlations were statistically significant in the Coastal sample.     

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.     

Family factors and somatic traits of newborns

The paper is focused on relationships between somatic traits of newborns and family factors. Data for 779 families and their offspirng born in hospitals of Bialystok and Zambrow were analyzed. Family factors were extracted based on a factor analysis of 23 family traits. Multiple regression analysis was used to find relationships between offspring traits and family factors. It has been found that the most important factor of the somatic development of the fetus is the body size of the mother and placenta weight (factor F5). The mother has a greater effect on the development of the child than the father does. Family culture (consciousness-F1) is an important factor during the prenatal devlopment, more important than socio-economic conditions of the family (F3). Also the effect of father's morbidity (factor F8) is relatively high, almost as high as the effect of mother's morbidity (factor F6), more important than the body build of the father (factor F7). Age of the parents and the number of earlier pregnancies (factor F2) have the lowest effect on somatic traits of newborns. Blood pressure of the mother (factor F4) has relatively little effect on the development of somatic traits in newborns. The traits most affected by family factors include frontal breadth, body weight, chest size, and hip breadth.     

Biological and ecological traits of benthic freshwater macroinvertebrates: relationships and definition of groups with similar traits

• 1 Relating species traits to habitat characteristics can provide important insights into the structure and functioning of stream communities. However, trade‐offs among species traits make it difficult to predict accurately the functional diversity of freshwater communities. Many authors have pointed to the value of working with groups of organisms as similar as possible in terms of relationships among traits and have called for definition of groups of organisms with similar suites of attributes.
• 2 We used multivariate analyses to examine separately the relationships among 11 biological traits and among 11 ecological traits of 472 benthic macroinvertebrate taxa (mainly genera). The main objective was to demonstrate (1) potential trade‐offs among traits; (2) the importance of the different traits to separate systematic units or functional groupings; and (3) uniform functional groups of taxa that should allow a more effective use of macroinvertebrate biological and ecological traits.
• 3 We defined eight groups and 15 subgroups according to a biological trait ordination which highlighted size (large to small), reproductive traits (K to r strategists), food (animal to plant material) and feeding habits (predator to scraper and/or deposit feeder) as ‘significant’ factors determining the ordination of taxa. This ordination partly preserved phylogenetic relationships among groups.
• 4 Seven ecological groups and 13 ecological subgroups included organisms with combinations of traits which should be successively more adequate in habitats from the main channel to temporary waters, and from the crenon to the potamic sections of rivers, and to systems situated outside the river floodplain. These gradients corresponded to a gradual shift from (1) rheophilic organisms that lived in the main channel of cold oligotrophic mountain streams to (2) animals that preferred eutrophic habitats of still or temporary waters in lowlands. The groups with similar ecological traits had a more diverse systematic structure than those with similar biological traits.
• 5 Monitoring and assessment tools for the management of water resources are generally more effective if they are based on a clear understanding of the mechanisms that lead to the presence or absence of species groups in the environment. We believe that groups with similar relationships among their species traits may be useful in developing tools that measure the functional diversity of communities.

     

Round and large: morphological and genetic consequences of artificial selection on the gourd tree Crescentia cujete by the Maya of the Yucatan Peninsula, Mexico

Background and Aims

Artificial selection, the main driving force of domestication, depends on human perception of intraspecific variation and operates through management practices that drive morphological and genetic divergences with respect to wild populations. This study analysed the recognition of varieties of Crescentia cujete by Maya people in relation to preferred plant characters and documents ongoing processes of artificial selection influencing differential chloroplast DNA haplotype distribution in sympatric wild and home-garden populations.

Methods

Fifty-three home gardens in seven villages (93 trees) and two putative wild populations (43 trees) were sampled. Through semi-structured interviews we documented the nomenclature of varieties, their distinctive characters, provenance, frequency and management. Phenotypic divergence of fruits was assessed with morphometric analyses. Genetic analyses were performed through five cpDNA microsatellites.

Key Results

The Maya recognize two generic (wild/domesticated) and two specific domesticated (white/green) varieties of Crescentia cujete. In home gardens, most trees (68 %) were from domesticated varieties while some wild individuals (32 %) were tolerated. Cultivation involves mainly vegetative propagation (76 %). Domesticated fruits were significantly rounder, larger and with thicker pericarp than wild fruits. Haplotype A was dominant in home gardens (76 %) but absent in wild populations. Haplotypes B–F were found common in the wild but at low frequency (24 %) in home gardens.

Conclusions

The gourd tree is managed through clonal and sexual propagules, fruit form and size being the main targets of artificial selection. Domesticated varieties belong to a lineage preserved by vegetative propagation but propagation by seeds and tolerance of spontaneous trees favour gene flow from wild populations. Five mutational steps between haplotypes A and D suggest that domesticated germplasm has been introduced to the region. The close relationship between Maya nomenclature and artificial selection has maintained the morphological and haplotypic identity (probably for centuries) of domesticated Crescentia despite gene flow from wild populations.     

Farm Households and Land Use in a Core Conservation Zone of the Maya Biosphere Reserve,Guatemala

This paper employs cross-tabular analysis, and multivariate and logistic regression to explore demographic, political-economic, socioeconomic, and ecological patterns of farm households and land use outcomes in an emergent agricultural frontier: the Sierra de Lacandón National Park (SLNP)-a core conservation zone of the Maya Biosphere Reserve (MBR), Petén, Guatemala. Data were obtained from a 1998 probability sample of 241 farm households, the first large detailed household land use survey in Guatemala’s Selva Maya-the largest lowland tropical forest in Central America. Virtually all settler households were poor maize farmers who colonized the SLNP in search of land for subsistence. While they faced similar ecological and economic conditions, land use strategies and patterns of forest clearing varied with demographic, household, and farm characteristics. Findings support and refute elements from previous frontier land use theory and offer policy implications for conservation and development initiatives in the Maya Forest specifically, and in tropical agricultural frontiers in general.

Biological traits of stream macroinvertebrates from a semi-arid catchment: patterns along complex environmental gradients

1. The relationships between biological traits of macroinvertebrates and environmental characteristics were investigated in streams with contrasting physical, chemical or landscape level attributes. We used an ordination technique, RLQ analysis, which links an environmental table (R) with traits table (Q) through an abundance table (L) to investigate the relationship between habitat characteristics and biological traits.
2. A major environmental axis explaining the distribution of species and their distinctive biological features was obtained. This axis included variables of anthropogenic pressure (agricultural and urban uses) and natural variability (climatic and geologic) that are strongly intercorrelated in the study area, with a clear spatial component.
3. The attributes of species from frequently disturbed systems (small size, multivoltinism, diapause, ovoviviparity, etc.) were associated with semi-arid areas whereas traits common in more stable and favourable environments (large body size, semi-voltinism, isolated eggs, etc.) were found in upland forested areas.
4. The natural climatic variation was proposed as a disturbance axis of a theoretical habitat templet (driven by the intense hydrological disturbances typical of semi-arid streams), while anthropogenic pressure (mainly intensive agriculture) and high salinity, a natural consequence of geology, was proposed as an adversity axis. Different life-histories associated with contrasting environmental features were superimposed in this habitat templet.
5. The ecological–evolutionary scenario in which stream macroinvertebrates have evolved and by which their communities are organized, is closely linked to disturbance, environmental harshness and human pressure.     

Age-specific variation in the secular trend for stature: A comparison of samples from industrialized and nonindustrialized regions

Age-specific secular trend patterns for children in industrialized world regions have a regular pattern, beginning low at age 6 and increasing to a maximum at age 10 to 14, then declining. While magnitude differs, the patterns are ordinarily parallel, especially in the female samples. However, age-specific secular trend values for children from developing regions, or from areas of industrialized countries not benefitting substantially from development, are irregular in pattern and magnitude. Consequently, it is difficult to predict age at maximal secular change. We suggest that fluctuating environmental circumstances in these developing countries influence growth and, hence, the pattern of secular trend. As more stable environmental conditions relating to growth are present in the industrialized countries, this leads to more stable patterns of growth and age-specific patterns of secular change.     

Antifungal properties of selected plants from the Yucatan peninsula,Mexico

A total of 20 plants belonging to different genera (Acalypha, Ageratum, Ambrosia, Bidens, Blechum, Caesalpinia, Calea, Carlowrightia, Croton, Eugenia (2), Furcraea, Stenandrium, Tephrosia, Trichilia (2), Randia (3), and Vitex) were selected from native flora of the Yucatan peninsula. All plants selected were collected and separated in to leaves, stems and roots. These were then extracted with ethanol and their crude extracts (54) were evaluated against Alternaria tagetica, Colletotrichum gloeosporioides, Fusarium oxysporum and Rhizopus sp. using the filter paper disc diffusion assay. Results lead to the selection of 33 crude extracts active against at least one of the target strains, which were assessed to determine their ability to inhibit the mycelial growth of the pathogenic fungi in a second antifungal assay. The results of this assay indicated that extracts from the roots of Croton chichenensis were the most promising, with a wide activity spectrum against all pathogens tested in both assays with inhibition percentages of greater than 60%. Furthermore, extracts from leaves of Ambrosia hispida, Trichilia minutiflora, and roots of Acalypha gaumeri were able to cause growth inhibition against two or three pathogen strains (≥50%). Studies of these active extracts should be continued at different levels. In general, results revealed a good bioactive potential of the flora from the Yucatan peninsula to produce metabolites with potential applications as botanical pesticides in the near future.     

Wild Meat Use and Traditional Hunting Practices in a Rural Mayan Community of the Yucatan Peninsula,Mexico

Overexploitation of Neotropical ecosystems for wild meat constitutes a threat to biodiversity and might seriously affect local people who depend on wild animals as a primary food resource. To assess this problem at the local level, social use of wild animals was evaluated in a Mayan community of the Yucatan Peninsula. Over 8 months, peasant-hunters carried out a total of 175 hunting trips, gathering 253 animals of 12 species (mammals, birds and reptiles). Most preys (95%) were taken in 4 months (January–April) during the dry season and the main target species were white-tailed deer and iguana (jointly representing 59% of preys). During an 11-week period, total per capita wild meat consumption (182 kg; n = 14 families) was three times greater in nuclear than in extended families. The observed wild fauna use is a reflection of traditional knowledge and represents an important subsistence strategy for the local people.     

Greta's Garbo: stranded seeds and fruits from Greta Beach, Christmas Island, Indian Ocean

Aim To describe the species composition of stranded seeds and fruits drifted by ocean currents to Christmas Island, Indian Ocean. Location Christmas Island, Indian Ocean. Methods Frequent visual searches along the strand line of the island's few accessible beaches over a 4-year period 1988–92, with most effort concentrated on Greta Beach, on the east coast. Results The collection contained not fewer than sixty-three species in forty-nine genera and twenty-nine families. Leguminous seeds were by far the most common (especially Caesalpinia bonduc (L.) Roxb., Dioclea spp., Entada spp., Erythrina spp. and Mucunagigantea (Willd.) DC.), but Calophyllum inophyllum L., Guettarda speciosa L., Hernandia ovigera L., Heritiera littoralis Aiton and Terminalia catappa L. were also common. Main conclusions Only about one-third of species recorded in the drift flora are native to the island, and most disseminules stranded on the island are probably not locally derived. The most likely distant sources of drift disseminules are probably the southern Indonesian islands and Sumatra, with most disseminules probably arriving via the Timor and Arafura Seas between Indonesia and Australia. However, some disseminules may originate from as far east as the Moluccas and the east coast of Kalimantan. The majority of species recorded in the drift flora are not native to the island, and yet some of these were encountered frequently and displayed a high degree of viability on arrival (e.g. Dioclea hexandra (Ralph) Mabb., Erythrina fusca Loureiro and Mucuna gigantea (Willd.) DC.). Several possible reasons for the failure of many drift species to establish on the island are discussed.     

Antifungal defenses of seagrasses from the Indian River Lagoon,Florida

We investigated the antifungal chemical defenses and physiological responses of five seagrasses collected from nearshore seagrass beds from the Indian River Lagoon, Florida, against a panel of co-occurring marine fungi isolated from nearby coastal communities. Whole plant tissues from Thalassia testudinum, Halodule wrightii and Syringodium filiforme prevented overgrowth by three of the seven fungi used in this study. Organic extracts from four of the five seagrasses inhibited the growth of at least one fungal strain. The extract from Ruppia maritima exhibited the highest antifungal activity, inhibiting the growth of three fungi including the pathogen Lindra thalassiae. Among the fungal panel, Fusarium sp. 2 was the most susceptible to seagrass extracts, whereas none of the extracts disrupted the growth of Dendryphiella salina and Fusarium sp. 3. Under laboratory conditions fungal inoculation elicited hydrogen peroxide production in all specimens within 25 min post-inoculation as measured with a redox sensitive dichlorodihydrofluorescein diacetate (DCFH-DA) assay. The concentration of H₂O₂ released into the immediate vicinity of infected seagrasses varied between 0.10 and 0.85 μmol g⁻¹ FW min⁻¹ depending on seagrass species and pathogen combination. Longer term incubation (days) of T. testudinum with homogenates of D. salina or L. thallasiae resulted in the induction of caspase activity, a known proteolytic activator of apoptotic and inflammatory activities. The application of micromolar concentrations of H₂O₂ to blades of T. testudinum induced caspase activity suggesting that fungal detection, H₂O₂ production, and caspase activation occur in a consecutive order. The seagrasses examined in this study appear to use a combined strategy to combat fungal infection, including microbial chemical defenses and signaling pathways observed in terrestrial plants.     

Biodiversity patterns in Indian Ocean corals, and effects of taxonomic error in data

Corals from 26 sites in the Indian Ocean, from numerous taxonomic sources, are analysed for distribution patterns after applying a consistent synonymy. The data set contains double the amount of distribution information used previously. Cluster analysis shows several contiguous regional groupings within this ocean, and no geographically dispersed groupings exist. Between-site species similarity correlates negatively with distance between sites. Coral species diversity and genus diversity plotted with latitude and longitude confirm that a band of high diversity stretches across the entire Indian Ocean, but that in this Ocean, unlike the Pacific and greater Caribbean area, there is no clear gradient with latitude at least up to the latitudinal limits of coral growth. About half the species are widespread throughout the Indian Ocean. Species frequency/distribution curves and cumulative frequency curves show that 150 species occur at only 2–4 sites. Multi-dimensional scaling (MDS) analysis using only these species confirms that they are important in forming sub-regional groupings which are superimposed on a general Indian Ocean homogeneity.The perennial problem of error in taxonomic data sets is examined. Increasing taxonomic error is introduced into the data using random methods. It is found that about 25% more error can be added to this data set before the relationship between similarity coefficient and geographical distance between pairs of sites is lost. Measures extracted from the clustering procedure using the original data and the data sets with added taxonomic error, show a sharp loss in cluster formation after addition of about 10 or 20% more error.     

Variation,selection and evolution of function-valued traits

We describe an emerging framework for understanding variation, selection and evolution of phenotypic traits that are mathematical functions. We use one specific empirical example – thermal performance curves (TPCs) for growth rates of caterpillars – to demonstrate how models for function-valued traits are natural extensions of more familiar, multivariate models for correlated, quantitative traits. We emphasize three main points. First, because function-valued traits are continuous functions, there are important constraints on their patterns of variation that are not captured by multivariate models. Phenotypic and genetic variation in function-valued traits can be quantified in terms of variance-covariance functions and their associated eigenfunctions: we illustrate how these are estimated as well as their biological interpretations for TPCs. Second, selection on a function-valued trait is itself a function, defined in terms of selection gradient functions. For TPCs, the selection gradient describes how the relationship between an organism's performance and its fitness varies as a function of its temperature. We show how the form of the selection gradient function for TPCs relates to the frequency distribution of environmental states (caterpillar temperatures) during selection. Third, we can predict evolutionary responses of function-valued traits in terms of the genetic variance-covariance and the selection gradient functions. We illustrate how non-linear evolutionary responses of TPCs may occur even when the mean phenotype and the selection gradient are themselves linear functions of temperature. Finally, we discuss some of the methodological and empirical challenges for future studies of the evolution of function-valued traits.     

Deep-sea nematodes from the Indian Ocean: new and known species of the family Comesomatidae

Twelve new and known species of the genera Sabatieria,Cervonema, Paramesonchium, Hopperia and Dorylaimopsis and one new genus, Kenyanema aredescribed from the Indian Ocean and S. pisinna Vitiello,1970 from the Mediterranean Sea. Sabatieria lucia sp. n.is characterised by short but distinct inner and setiformouter labial sensilla and long (4–5 µm or 30–33% hd)cephalic sensilla; S. conicauda Vitiello, 1970, ischaracterised by tiny inner and outer labial sensilla andsetiform cephalic ones and short and thick cylindrical tail;Sabatieria pisinna is characterised by short innerand outer labial sensilla, setiform (3µm long) cephalicsensilla, multispiral amphids with 3.25–3.5 turns and a tailwhich is conical in the anterior 2/3 and posterior 1/3cylindrical; Cervonema tenuicauda Schuurmans Stekhoven,1950, is characterised by anterior sensilla in twocircles which are equal in length (3µm long), multispiralamphids with 3–4 turns and located at 1.5 times hd from theanterior end, simple spicules one abd long and 6–7 fineprecloacal supplements; Cervonema minutus sp. n.characterised by an extremely attenuated anterior end,spiral amphids with 4–5 turns (80–90% cbd) and short,simple spicules (0.8 abd long); Cervonema gourbaulti sp.n. characterised by long (4–5 µm) labialand cephalic sensilla, spiral amphids with 5–6 turns(73–88% cbd) and an elongate crenate terminal pharyngealbulb; Paramesonchium mombasi sp. n. characterised bylong labial (5 µm) and cephalic (21 µm) sensilla thatare close together and wide amphids (80–90% cbd); Kenyanema monorchis gen. et sp. n. characterised bya head region narrower than the rest of the body, fourcephalic sensilla (3 µm long) and spiral amphids with1.5–2 turns; Hopperia indiana sp. n. characterised byshort conical anterior sensilla, arcuatespicules that have a velum and a gubernaculum with a longand sharp pointed apophysis; Dorylaimopsis coomansi sp.n. characterised by long (8–10µm) cephalic setae,cuticular punctation with lateral differention of irregularlyarranged dots at the pharyngeal region and 1–3longitudinal rows of dots posterior of the pharynx; spiculeswith a unique shape; Dorylaimopsis gerardi sp. n.characterised by short setiform labial and long (6–7 µm)cephalic sensilla, punctated cuticle with lateraldifferentiation of irregularly arranged dots at firstthen three or four irregularly arranged longitudinal rows atthe pharyngeal and tail regions and two regularly arrangedlongitudinal rows of dots on the rest of the body, aconico-cylindrical tail with a distinctly swollen tip;Dorylaimopsis variabilis sp. n. is characterised byshort labial and setiform cephalic sensilla (33–58% hd),multispiral amphids with three turns, cuticular punctationswith lateral differentiation of three longitudinalrows at the pharyngeal and tail regions and two longitudinalrows on the rest of the body, spicules that are thin andslightly arcuate. The position of S. pisinna accordingto the grouping of Platt, 1985 of Sabatieriaspp. is also discussed. Kenyanema monorchis representsthe first monorchic species in the family.