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1.
The genus Capsicum is New World in origin and represents a complex of a wide variety of both wild and domesticated taxa. Peppers or fruits of Capsicum species rarely have been identified in the paleoethnobotanical record in either Meso- or South America. We report here confirmation of Capsicum sp. residues from pottery samples excavated at Chiapa de Corzo in southern Mexico dated from Middle to Late Preclassic periods (400 BCE to 300 CE). Residues from 13 different pottery types were collected and extracted using standard techniques. Presence of Capsicum was confirmed by ultra-performance liquid chromatography (UPLC)/MS-MS Analysis. Five pottery types exhibited chemical peaks for Capsicum when compared to the standard (dihydrocapsaicin). No peaks were observed in the remaining eight samples. Results of the chemical extractions provide conclusive evidence for Capsicum use at Chiapas de Corzo during a 700 year period (400 BCE–300 CE). Presence of Capsicum in different types of culinary-associated pottery raises questions how chili pepper could have been used during this early time period. As Pre-Columbian cacao products sometimes were flavored using Capsicum, the same pottery sample set was tested for evidence of cacao using a theobromine marker: these results were negative. As each vessel that tested positive for Capsicum had a culinary use we suggest here the possibility that chili residues from the Chiapas de Corzo pottery samples reflect either paste or beverage preparations for religious, festival, or every day culinary use. Alternatively, some vessels that tested positive merely could have been used to store peppers. Most interesting from an archaeological context was the presence of Capsicum residue obtained from a spouted jar, a pottery type previously thought only to be used for pouring liquids.  相似文献   

2.
This study concerns the knowledge and selection of biological diversity of maize (Zea mays) within its center of domestication in Mesoamerica. Maize farmers in central Chiapas of Southern México keep local varieties (landraces) belonging to six races and four race mixtures. Fifteen local varieties are recognized. In spite of widespread adoption of a modern, high yielding variety, maize farmers continue to select local varieties for specific soils and because of agronomic and use criteria. Farmers maintain maize varieties primarily through seed selection. Spatial and temporal separation do not seem sufficient to maintain varieties. The management of improved varieties can lead from a uniform population to a heterogeneous one as hybridization with local maize populations occurs.  相似文献   

3.
Simulium blackfly larvae (Diptera: Simuliidae) were collected from rivers and streams at 500-1500 m a.s.l. in Chiapas State of southern Mexico. Among 45 sites surveyed over an area of 2300 km2 (around 15 degrees 15'N 92 degrees 20'W), some Simulium larvae from three sites were opalescent violet-blue, interpreted as patent infection with invertebrate iridescent virus (IIV). Dissection confirmed the presence of putative Iridovirus particles, 130nm diameter, but no IIV isolates were obtained from homogenates injected into Galleria mellonella (L) larvae (Lepidoptera: Pyralidae). All Simulium with patent IIV infection died before metamorphosis, whereas approximately 60% of asymptomatic Simulium survived to adulthood in the laboratory. During 1997, standard monthly samples from two parallel rivers 42-50 km north-west of Tapachula comprised the following species proportions (and rates of patent IIV infection): 41.8% (47%) Simulium mexicanum Bellardi complex, 31.3% (31.4%) S. rubicundum Knab, 10.1% (13.1%) S. paynei, 6.5% (2.9%) S. callidum (Dyar & Shannon), 6.3% (5.1%) S. ochraceum Walker complex, 3.1% (0.7%) S. downsi Vargas et al., 0.7% S. samboni Jennings and 0.2% S. metallicum Bellardi complex, showing a strong correlation between blackfly abundance and the prevalence of patent infection. An epizootic of IIV in January and February (infection rates 41-100%) was followed by absence of larvae (March-August) until the end of the rainy season, when numbers collected on nylon strings rose to approximately 1/cm with patent IIV infection rates of 0-12.5% during September-December. Further investigations are underway to isolate this IIV and assess its potential usefulness for biological control of Simulium pests and vectors of onchocerciasis.  相似文献   

4.
Spider diversity in a tropical habitat gradient in Chiapas, Mexico   总被引:3,自引:0,他引:3  
This paper presents an assessment of spider diversity in a complex landscape of southern Mexico. Eighteen different habitats were identified, measured and mapped across this fragmented landscape. Habitat types were characterized by measuring various features, including number of plant forms, tree cover and litter depth. Each month from February to April (dry season) and from June to August 2002 (wet season), spiders were sampled on each habitat by using pitfall traps and direct collection. Correlations between spider diversity and habitat characteristics were carried out to explore the relative contribution of each habitat variable as related to changes in spider composition and richness. In total, 115 spider species were recorded in 18 habitat types, and the mean number and density of species per habitat were 21 (± 3, standard error of mean) and 57 (± 9), respectively. The species recorded represent 41% of the fauna recorded in the Mexican state of Chiapas and 4% of the fauna recorded in Mexico. Relatively pristine habitats (e.g. deciduous forest) contained an important proportion of spider diversity in this fragmented landscape. Epigean spider diversity was significantly correlated with tree cover and with the diversity of plant forms during the rainy season. No correlation was detected between soil spider diversity and the habitat variables measured for any season. The results of this work suggest that in highly fragmented tropical landscapes, some habitat types (e.g. coffee plantations, hedgerows) might play an important role for the persistence of spider populations. The prevalence of relatively stable conditions in some of these habitats can allow spiders species (e.g. Nephila clavipes ) to overcome adverse conditions such as a decrease in humidity and dramatic changes in temperature and wind exposure, allowing them to recolonize when favourable conditions return.  相似文献   

5.
Little is known about the population characteristics of Alouatta pigra under conditions of forest fragmentation-information that is important to understanding its tolerance to habitat loss. In this work we present data on forest loss and on troop size, age, and sex composition for a population of black howler monkeys existing in the fragmented landscape surrounding the Mayan site of Palenque, Chiapas, Mexico. Two aerial photos (1:70,000) of the study area (261 km(2)) taken in 1984 and 2001 were examined to assess forest loss. Between June and December 2001 and January and March 2002 we surveyed 44 forest fragments for the presence of howler monkeys. Examination of aerial photos showed that 33% of the forest present in 1984 had disappeared by 2001, and detected an increment in the number of forest fragments present in the landscape. We discovered a total of 115 howler monkeys living in 22 of the 44 forest fragments studied, of which 107 were members of 18 troops. The rest were solitary males or small groups of males living in isolated forest fragments. Troop size ranged from two to 15 individuals (mean 5.9+3.0 ind). 31% and 15% of individuals in the troops were juveniles and infants, respectively, suggesting continued reproductive activity. Howler monkey troops in the forest fragments were on average smaller (5.9+/-3.0 ind) than troops in the nearby protected forest of the Mayan site (7.0+/-2.8 ind). The mean density of howlers in the forest fragments was 119+/-82.9 ind/km(2). The establishment of corridors is suggested as a possible conservation scenario for the fragmented howler population investigated, and as a conservation measure to connect this population with the howler population found in the protected forest of the Mayan site.  相似文献   

6.
This survey investigated the prevalence of ethnomedical syndromes and examined treatments and treatment-seeking in Mayan Guatemalans living in United Nations High Commissioner for Refugee (UNHCR) camps in Chiapas, Mexico. Methods included a rapid ethnographic assessment to refine survey methods and inform the cross-sectional survey, which also examined mental health outcomes; 183 households were approached for interview, representing an estimated 1,546 residents in five refugee camps and 93% of all households. One adult per household (N = 170) was interviewed regarding his or her health; an additional 9 adults in three surveyed households participated and were included in this analysis; of the 179 participants, 95 primary child-care providers also answered a children’s health questionnaire for their children. Results indicated that ethnomedical syndromes were common in this sample, with 59% of adults and 48.4% of children having experienced susto (fright condition) and 34.1% of adults reporting ataques de nervios (nervous attacks); both conditions were significantly associated with symptoms consistent with posttraumatic stress disorder, anxiety and depression and are mental health conditions recognized by the American Psychiatric Association. Combining healthcare provider and indigenous treatments such as physician prescribed medication (65%), medicinal plants (65.7%), and limpias (spiritual cleansings) (40.6%) was reported. Most participants (86%) sought routine medical treatment from UNHCR trained health promoters in their camp. Assessing ethnomedical health is important for informing mental health programs among this population.  相似文献   

7.
The behavior of spider monkeys (Ateles geoffroyi) at sleeping sites and the characteristics of these sites were studied in Santa Rosa National Park, Costa Rica. The spider monkeys tended to congregate just prior to dusk at a number of sleeping sites which were repeatedly used (81.6%), but occasionally they slept in trees which were only used once (18.4%). All of the regularly used sleeping trees were not used concurrently, but rather, there was a rotation between sites. In general, males were not encountered at regularly used sleeping sites as often as other age/sex classes, and when they were in all male subgroups, they did not sleep in repeatedly used sites. The trees used as regular sleeping sites tended to be large, but such trees were common in the group's home range. The size of the subgroups attending repeatedly used sleeping trees was large when food was abundant and small when food was scarce. It is suggested that this relationship reflects that the costs of travelling to the sleeping site would be more easily recovered when food was abundant than when food was scarce.  相似文献   

8.
In order to evaluate the usefulness of rapid surveys of indigenous knowledge for assessing trends in biodiversity, a case study was undertaken in two rural communities, Juznajab and Muquenal, in Chiapas, Mexico. This involved the use of a variety of rapid rural appraisal (RRA) and participatory rural appraisal (PRA) techniques, including semi-structured interviews, transect walks and participatory mapping. These approaches were used in conjunction with analysis of land use maps and aerial photographs to evaluate recent changes in vegetation cover and abundance of utilised species. In both communities, the extent of forest cover was considered by local people to have declined substantially in recent decades, with an annual decline in forest cover of 0.3% and 0.6% estimated by local people in Juznajab and Muquenal, respectively. Results from RRA indicated that this has been accompanied by significant declines in the abundance of useful species. In Juznajab 60% and 79%, and in Muquenal 96% and 85% of plants and animal species, respectively, were considered to have declined within living memory. These declines appear to result from over-utilization as well as habitat changes. For example, most of the tree species used for timber and the animal species used for meat were considered to have declined substantially in both communities. These results indicate that indigenous knowledge is potentially a valuable source of information about biodiversity trends, which could be assessed during Rapid Biodiversity Assessments and incorporated into the process of resource management by local communities. However, the contradictions recorded between assessments of vegetation change by local people and data obtained from other sources indicates the need for caution in the use of indigenous knowledge for this purpose.  相似文献   

9.
Aim We aim to assess regional patterns in the distribution and species richness of vascular epiphytes with an emphasis on forests that differ in altitude and the amount of rainfall. Location Tropical America, in particularly the 75,000 km2 large state of Chiapas in southern Mexico at 14.5–18.0°N. Chiapas is diverse in habitats with forests from sea‐level to the tree‐line at c. 3800 m altitude and with annual amounts of rainfall ranging from 800 to over 5000 mm. It is also one of the botanical best‐explored regions in the tropics. Methods First we give an overview of epiphyte inventories to date. Such epiphyte surveys were mostly carried out on the basis of surface area or individual trees and we discuss their problematic comparison. Applying a different methodological approach, we then used 12,276 unique vascular epiphyte plant collections from Chiapas that are deposited in various botanical collections. The locality data were georeferenced and compiled in a relational data base that was analysed using a geographical information system. To compare the number of species between inventories that differed in the numbers of records, we estimated the total richness, SChao, at each. Results We recorded 1173 vascular epiphyte species in thirty‐nine families (twenty‐three angiosperms), comprising c. 14% of all confirmed plant species in the state. About half of all species were orchids (568). Ferns and bromeliads were the next species‐rich groups with 244 and 101 species, respectively. Most species were found in the Montane Rain Forest and in the Central Plateau. Trees of different forest formations, rainfall regimes, altitudes and physiographical regions supported a characteristic epiphyte flora. Main conclusions We were able to confirm the presumed presence of a belt of high diversity at mid‐elevations (500–2000 m) in neotropical mountains. In contrast to predictions, however, we observed a decrease in diversity when the annual amount of rainfall exceeded 2500 mm. The decrease is attributed to wind‐dispersed orchids, bromeliads and Pteridophyta that may find establishment problematical under frequent downpours. In the wet but seasonal forests in Chiapas, this decrease is not compensated by plants in the animal‐dispersed Araceae that are abundant elsewhere. We presume that in addition to the annual amount of rainfall, its distribution in time determines the composition of the epiphyte community.  相似文献   

10.
11.
Shade-grown coffee is an agricultural system that contains some forest-like characteristics. However, structure and diversity are poorly known in shade coffee systems. In 61 coffee-growers' plots of Chiapas, Mexico, structural variables of shade vegetation and coffee yields were measured, recording species and their use. Coffee stands had five vegetation strata. Seventy seven woody species mostly used as wood were found (mean density 371.4 trees per hectare). Ninety percent were native species (40% of the local flora), the remaining were introduced species, mainly fruit trees/shrubs. Diametric distribution resembles that of a secondary forest. Principal Coordinates Analysis grouped plots in four classes by the presence of Inga, however the majority of plots are diverse. There was no difference in equitability among groups or coffee yields. Coffee yield was 835 g clean coffee per shrub, or ca. 1,668 kg ha-1. There is a significant role of shade-grown coffee as diversity refuge for woody plants and presumably associated fauna as well as an opportunity for shade-coffee growers to participate in the new biodiversity-friendly-coffee market.  相似文献   

12.
This case study of the organic farmers' cooperative Indigenas de la Sierra Madre de Motozintla (ISMAM) explores the construction of identity as a dialogic process in which external elements are appropriated to permit resistance and creative adaptation to global processes. Building on indigenous Mam respect for nature, ISMAM forges a corporate image that responds to symbolic demands of the alternative marketplace and a self-image reaffirming traditional values in a modern context.  相似文献   

13.
Soil Diversity and Land Use in the United States   总被引:7,自引:0,他引:7  
Soils are dynamic components of terrestrial ecosystems that historically have been viewed as economic resources by government and private interests. The large-scale conversion of many sections of the United States to agriculture and urban land uses, combined with the growing awareness of the role of soils in global biogeochemistry and ecology, ultimately requires an assessment of the remaining distribution of undisturbed soils in the country. Here we conduct the first quantitative analysis of disturbed and undisturbed soil distribution in the USA using a GIS-based approach. We find that a sizable fraction (4.5%) of the nation's soils are in danger of substantial loss, or complete extinction, due to agriculture and urbanization. In the agricultural belt of the country, up to 80% of the soils that were naturally of low abundance are now severely impacted (greater than 50% conversion to agricultural/urban uses). Undisturbed soils provide ecosystem services that warrant their preservation, including a somewhat complex relationship with rare or endangered plants. The known and unknown attributes of undisturbed soils suggests the need for an integrated biogeodiversity perspective in landscape preservation efforts.  相似文献   

14.
We present floristic and structural data on serai plant communities (Old-Field, Grassland, Shrubland, and Early Successional, Mid-Successional, and Mature Forest) resulting from the current land use pattern in the Pinus-Quercus forests in the highlands of Chiapas, Mexico. The number of species ranged from 24 in the Old-Field stage up to 100 in the Mature Forest, and the shrub layer was richest in all the forested stands. An almost complete floristic replacement exists between the open and the forested communities. Quercus and Pinus dominate the canopy of old-growth stands, but their recruitment does not occur or is very low in the shade. Vigorous seedlings and saplings of these species are found only in the open serai stages or in forest gaps. Demographic and phytosociological data are used to indicate the successional role of dominant species in the forested stages. Some implications of the regional land use patterns for conservation and succession are discussed.  相似文献   

15.
16.
Due to the current environmental crisis, many animal species face extinction problems. Amphibian populations have been affected by this crisis. Our goal is to study amphibian species diversity in Chiapas, which has 7.6% of the endemic amphibians in Mexico and 53 protected areas. Only 58% of the protected areas have management plans or information on their resident amphibians. We aim to determine the extent of protection provided by the network of natural areas for the conservation of amphibian species in the state and to discuss the effectiveness of this protection. Therefore, we compiled a georeferenced database of 112 amphibian species in Chiapas to create each distribution model. In addition, we carried out representativeness, beta diversity, and species richness analyses. As a result, we obtained a high degree of representativeness for the records and species distribution models. However, we found a decrease in the richness of amphibians involving 20% of total species, 13% of endemics, 18% threatened according to NOM-059, and 31% threatened according to IUCN between 1800 and 2020 and 1980–2020. We also identified two biodiversity hotspots in the Sierra Madre de Chiapas and the Northern Highlands physiographic regions. Finally, based on potential distributions, we found more endemic and threatened species outside protected natural areas than inside them. Our results give a broader picture of how amphibian richness is distributed in Chiapas. This information can help to prioritize conservation efforts toward those areas rich in threatened or endemic species, such as the Northern Mountains Hotspot we identified in northern Chiapas.  相似文献   

17.
1. We evaluated the potential of small, isolated cornfields embedded in a large forest matrix as an appropriate compromise between conservation and sustainable development.
2. We examined the relationship between habitat structure and diversity with overall mammal species richness and abundance of six common small mammals in four 6-year-old abandoned cornfields (oldfields) and four continuous rainforest sites in the most speciose region in Mexico, the Selva Lacandona, Chiapas.
3. Species richness did not differ between forests and oldfields, indicating that forest-dependent mammals penetrate oldfields of size 0·9–2·9 ha, presumably because forest cover and resources are nearby. Even species which strongly selected forest habitat, such as H. desmarestianus and D. marsupialis , were present in oldfields, and only the latter showed a significant decline in the number of captures as a function of distance from forest edge.
4. The Lacandon Indian use of the land for agriculture in the form of small (> 3 ha) agricultural plots embedded in a large forest matrix increases spatial heterogeneity and promotes mammal diversity.
5. Those small plots (in agricultural production terms) are intermediate in size when the whole continuum of the local natural and anthropogenic disturbance sizes are considered; more common are the extensive clearings for agriculture or cattle ranching, whereas the most common forest disturbance is treefall gaps, at least 20 times smaller than oldfields.
6. This form of land use should be considered as an important, appropriate productive element when decisions are made about managing reserves and pursuing sustainable development.  相似文献   

18.
This study describes the foraging ecology of birds during summer and winter in two different types of coffee agroecosystems in Chiapas, Mexico. Avian foraging behavior is documented in two agroecosystems of differing management intensity, structurally similar but with different levels of floristic diversity, during summer and winter seasons. The distribution of tree species used by birds was more even, and birds used a greater diversity of tree species, in the more diverse coffee shade system. Much of the variation in resource use derived from shifts in the use of flowers and fruit, highlighting the importance in resource phenology for birds. Insectivory was more frequent in winter than summer for the coffee layer, and in summer for the shade layer. Given the vegetative structural similarity of the two coffee agroecosystems included in this study, floristic differences probably accounted for much of the difference in the bird communities between the management systems, especially given the strong seasonal response to flowering and fruiting. This work suggests that plentiful and diverse food resources associated with the high diversity of plant species may facilitate coexistence of the high number of bird species found in shade-grown coffee agroecosystems.  相似文献   

19.
Host-specificity is an intrinsic feature of many bacterial pathogens, resulting from a long history of co-adaptation between bacteria and their hosts. Alpha-proteobacteria belonging to the genus Bartonella infect the erythrocytes of a wide range of mammal orders, including rodents. In this study, we performed genetic analysis of Bartonella colonizing a rodent community dominated by bank voles (Myodes glareolus) and wood mice (Apodemus sylvaticus) in a French suburban forest to evaluate their diversity, their capacity to recombine and their level of host specificity. Following the analysis of 550 rodents, we detected 63 distinct genotypes related to B. taylorii, B. grahamii, B. doshiae and a new B. rochalimae-like species. Investigating the most highly represented species, we showed that B. taylorii strain diversity was markedly higher than that of B. grahamii, suggesting a possible severe bottleneck for the latter species. The majority of recovered genotypes presented a strong association with either bank voles or wood mice, with the exception of three B. taylorii genotypes which had a broader host range. Despite the physical barriers created by host specificity, we observed lateral gene transfer between Bartonella genotypes associated with wood mice and Bartonella adapted to bank voles, suggesting that those genotypes might co-habit during their life cycle.  相似文献   

20.
Located within Mexico’s Montes Azules Biosphere Reserve, the Tzendales River is part of the Usumacinta River Basin, which supports the largest diversity of cichlid fishes in Middle America. We evaluated temporal and spatial variation of species richness and distribution of cichlids in the Tzendales River; we collected 14 species with nine native and five endemic. The species with greatest relative abundances and broadest spatial distributions were Vieja intermedia and Amphilophus nourissati; and the rarest and most spatially restricted species were Thorichthys meeki and Parachromis friedrichsthalii. Environmental characteristics varied seasonally although fish assemblages and distributions were relatively stable over time. Based on habitat use patterns, three species associations were observed: (1) Amphilophus nourissati, Petenia splendida, Vieja argentea, V. bifasciata, V. intermedia, V. pearsei, V. synspila and V. ufermanni; (2) ‘Cichlasoma’ salvini and Parachromis friedrichsthalii; and (3) Thorichthys helleri and Thorichthys meeki. Two rheophilic species, Theraps lentiginosus and Theraps irregularis, had low habitat overlap with all of the other cichlid species. Canonical correspondence analysis showed that the depth, current speed and quantity of rocks in the substrate defined the spatial distribution of species in dry season. Cichlids of the Tzendales River appear to partition habitat in a manner that reduces resource competition.  相似文献   

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