Cnemidophorus costatus barrancorum was studied in the short-tree forest of southeastern Sonora, Mexico from November 1985 to December 1988. Adult females varied in snout-vent length from 71 to 101 mm, while males reached a maximum of 121mm. Ontogenetic change in color-pattern was pronounced, however sexual dimorphism in color-pattern was slight. The mean number of dorsal scales around mid-body was 99.4. Mating occurred in late July. Females laid two clutches of eggs per season, with clutch size varying from 2-8 (X = 4.2). The maximum shelled egg dimensions were 10.5mm x 15.6mm. Hatchlings appeared in early fall, and were surface-active throughout November. Yearlings emerged from hibernation in February-March. Adults were active from mid-spring into September. C. c. barrancorum had a unimodal daily activity pattern, with activity beginning when air temperature exceeded 30°C. The mean body temperature of surface-active animals was 40.0°C.

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No description available.

A study of the Helminthoglyptidae of Sonora was undertaken to determine the extent of their distribution and speciation. As a result, nine new species of Sonorella are described, and new ranges of the known species are given. The status of the family is reviewed and its standing is supported with the analysis of morphological characteristics of several genera. The zoogeography of the family and its distribution are shown. Possible dispersal and isolation mechanisms are discussed in order to explain the present distribution of these snails, and comments on ecological and speciation accounts are offered.

A necessary pre-requisite to the development of effective food and development policies involves understanding the intermediate steps and relationships between income and nutritional status. This study focuses on the social and cultural factors which are of importance in the determination of dietary patterns under normal circumstances. Four populations were studied (a total of 105 households) in Sonora, Mexico, an area of prevalent mild to moderate malnutrition: rural residents of Arroyo Lindo, migrants from there to Hermosillo, households in which both husband and wife were born in Hermosillo, and households with an American wife. The social and cultural variables investigated included: income, subsistence pattern, prestige, material culture, ethnicity, women's roles, intrahousehold food distribution, rural-urban residence, and nutritional knowledge. Data were collected over a 4-8 day period for each household on both actual food consumption (3 1-day recalls for each member of the household) and ethnographic aspects of dietary patterns. It was found that all of the variables interact through the "invisible variable" of available income. This refers to income which is available to those responsible for household expenditures to spend on houshold needs, including food. In Sonora, it includes the husband's and/or wife's earnings, plus that portion of any other household wage earner's income which is given to either the husband or wife. Husbands and wives use their incomes primarily for household needs, while other wage earners do not contribute equivalent proportions of their earnings to the household. This results in differences between total household income and available income. While husbands (and men in general) tend to retain more of their earnings for personal expenses than do wives (and women in general), calculation of available income focused on role, rather than gender of the wage earner. Using the concept of available income makes it clear that the interaction of the other variables and their effect on dietary patterns is through affecting the amount of available income, or how this amount is allocated. The importance of social and cultural variables in affecting dietary patterns is demonstrated by considering the ways their manipulation might ameliorate Sonoran nutritional problems.

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No description available.

No description available.

The purpose of this study was to analyze strategies for sustainable development, and especially the opportunities and constraints for sustainable development in arid lands. This study examines how environmental, economic, political, and social factors influence regional development. Because of the complexity of the problem, a two-perspective interdisciplinary approach was used. First, from a historical perspective, a farming systems approach focuses on understanding the interaction of population, environmental, technological and institutional factors. Second, and from an economic perspective, a linear progranuning model examines the interaction of the North American Free Trade Agreement (NAFTA) as well as the Amendment to Article 27 of the Mexican Constitution in regional-level current and expected transformations. Research was conducted in central Sonora, located in northwest Mexico, one of the arid zones of the Sonoran desert. From colonial times to the early 20th century chaotic changes occurred in Sonora. These changes were influenced by cultural, environmental, and technological factors. Cultural differences between the indigenous Sens and Spaniards prompted a long period of conflict. Seris were a hunter-gatherer nomadic group, the Spanish conquerors searched for gold and minerals, and the later Mestizos were farmers and ranchers. The strategy of hunting-gathering not only permitted the Seris to cope with a hostile, arid climate, but also helped them resist Spanish efforts to colonize or exterminate them. In contrast, environmental barriers limited the introduction of agricultural systems into the Seri territory and limited the rapid conquest of the Sens as well. Nonetheless, the Seris were nearly exterminated as a result of this conflict, and their territory reduced to the coastal margins of the Gulf of California.

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