Microbial Interactions: Bacteria Talk to (Some of) Their Neighbors

A recent study reports that Bacillus subtilis biofilm formation depends upon paracrine signaling where the signal-producing and target-responsive cells are different.     

Migration and Ethnicity in Chinese History: Hakkas, Pengmin, and Their Neighbors.

Migration and Ethnicity in Chinese History: Hakkas, Pengmin, and Their Neighbors. Tim Wright. ed. Stanford, CA: Stanford University Press, 1997. 234 pp.     

Ashkenazi Jews in Mexico: Ideologies in the Structuring of a Community

Ashkenazi Jews in Mexico: Ideologies in the Structuring of. Community. Adina Cimet. Albany: State University of New York Press, 1997. 231 pp.     

Community ecology of the Middle Miocene primates of La Venta,Colombia: the relationship between ecological diversity,divergence time,and phylogenetic richness

It has been suggested that the degree of ecological diversity that characterizes a primate community correlates positively with both its phylogenetic richness and the time since the members of that community diverged (Fleagle and Reed in Primate communities. Cambridge University Press, New York, pp 92–115, 1999). It is therefore questionable whether or not a community with a relatively recent divergence time but high phylogenetic richness would be as ecologically variable as a community with similar phylogenetic richness but a more distant divergence time. To address this question, the ecological diversity of a fossil primate community from La Venta, Colombia, a Middle Miocene platyrrhine community with phylogenetic diversity comparable with extant platyrrhine communities but a relatively short time since divergence, was compared with that of modern Neotropical primate communities. Shearing quotients and molar lengths, which together are reliable indicators of diet, for both fossil and extant species were plotted against each other to describe the dietary “ecospace” occupied by each community. Community diversity was calculated as the area of the minimum convex polygon encompassing all community members. The diversity of the fossil community was then compared with that of extant communities to test whether the fossil community was less diverse than extant communities while taking phylogenetic richness into account. Results indicate that the La Ventan community was not significantly less ecologically diverse than modern communities, supporting the idea that ecological diversification occurred along with phylogenetic diversification early in platyrrhine evolution.     

Edible begonias from the North of Puebla, Mexico

The Sierra Norte de Puebla, Mexico, is a region with biological and cultural diversity, where the use of local natural resources was increased by the relative isolation of the region until recent decades. There are more than 600 useful plants reported. In the Sierra Norte de Puebla at least six Begonia species are used as food. The objective of this paper is to report such species that are utilized for self-supply and for sale in local markets. The management includes gathering among wild populations, transplanting of rhizomes and vegetative propagation by leaves to establish and increase populations in home gardens and in coffee plantations.     

Test of the relationship between sutural ossicles and cultural cranial deformation: Results from Hawikuh,New Mexico

A number of researchers have hypothesized that the biomechanical forces associated with cultural cranial deformation can influence the formation of sutural ossicles. However, it is still difficult to make definitive conclusions about this relationship because the effects appear to be quite weak, and contradictory results have been obtained when specific sutures and deformation types are compared across studies. This research retests the hypothesis using a single archeological sample of lamdoidally deformed, occipitally deformed, and undeformed crania from Hawikuh, New Mexico (AD 1300–1680). Our results show no significant difference in either the prevalence or number of ossicles between deformed and undeformed crania, suggesting that the abnormal strains generated by cranial shape modification during infancy are not a factor in ossicle development for this population. One significant relationship was detected at the right lambdoid suture in crania with asymmetrical occipital deformation. Crania that were more deformed on the left side showed greater numbers of ossicles on the right side, but the effect was small. Furthermore, the relationship may well reflect a sampling error, due to the small number of crania with greater left side deformation and scorable right side lambdoid ossicles (n = 11). Although it is possible that forms of cranial deformation other than the posterior tabular types examined here may affect ossicle expression, our review of the literature suggests that the relationship in humans is complex and incompletely understood at this time. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.     

Vegetated Field Margins in Mexico: Their History, Structure and Function, and Management

We explore the history, structure and function, and management of vegetated field margins, particularly hedgerows, in Mexico since the pre-Hispanic period. We then focus on the current agricultural landscape in El Bajío, central Mexico, describing in detail the abundance, composition, and management of existing hedgerows. These vegetated field margins can be traced to the pre-Hispanic period, especially in central Mexico, where Indians planted hedgerows, living fences, and terraces, mainly to prevent erosion. After the Spanish Conquest, some of these structures disappeared, but in many cases, new plant species were incorporated into the remaining field boundaries. Today, vegetated field boundaries are adjacent to crop fields and, in some places, they form networks similar to those seen in Europe. Farmers actively manage hedgerows for a variety of useful products and in so doing provide habitat and dispersal routes for native plants and animals.     

Investigations of North American cycadeoids: Williamsonian cones from the Jurassic of Oaxaca,Mexico

A study of williamsonian cones from Middle Jurassic rocks of Oaxaca, Mexico, indicates that Weltrichia mexicana (Wieland) Harris (formerly Williamsonia mexicana) is probably not a fructification. Ovulate cones recognized from localities near Tezoatlán are Williamsonia netzahualcoyotlii Wieland, W. oaxacensis sp. nov., W. huitzilopochtlii Wieland, and W. diquyui sp. nov. Notable is the similarity among williamsonian cones in Jurassic rocks of such widely separated places as Oaxaca, Mexico, Yorkshire, England, and Rajmahal Hills, India. The mode of preservation of williamsonian cones suggest a growth habit involving slender, branched stems with exposed cones that abscised from the plants on which they were borne. Conceivably, further development, including fertilization, could have occurred after the cones were dropped.     

Transforming the Safety Net: Responses to Medicaid Managed Care in, Rural and Urban New Mexico

In this article we examine the impact of Medicaid managed care on safety net organizations in New Mexico and their ability to maintain their traditional mission of charity care. We address two particular areas of concern that have arisen in the literature on Medicaid managed care. First, analysts have debated under what circumstances safety net organizations are better positioned to survive under market competition without abandoning their social orientation. Second, analysts have suggested that populations in rural areas may be more disadvantaged under Medicaid managed care due to its intensification of already-existent barriers to access. By comparing the differential ability of safety net organizations in rural and urban New Mexico to buffer their patients from potentially harmful effects of Medicaid managed care, we identify factors that place these safety nets particularly at risk. We find that a rural location, lack of affiliation with a larger organization, and lack of recourse to charitable funding are "risk factors" determining who sinks—and who floats—in this new competitive health care system, [privatization of health care, Medicaid safety net organizations, managed care, resistance, ruralurban]     

Associations of zooplankton in six crater lakes in Arizona, Mexico and New Mexico

Zooplankton associations in six crater lakes have been compared by means of indices of similarity and diversity, and by k -dominance curves. The lakes covered a wide range of salinities and vegetational characteristics.
The total number of species identified were: Protozoa, 34; Rotifera, 48; Gastrotricha, 7; Crustacea, 24; and Chaoborus larvae, 2; giving an overall total of 115. The numbers of zooplankton species in each lake varied from 68, in a richly vegetated fresh crater lake in Arizona, to one in a highly saline lake in New Mexico.
Testate rhizopods and gastrotrichs were not found in the more saline lakes. A comparison of the rotifer associations with those of crater lakes in other parts of the world shows that there is a general tendency for a reduction in the total number of species when the conductivity rises above 400 μS cm⁻¹ 20°C, and when the conductivity reaches 10,000 μS cm⁻¹ 20°C the number of rotifer species is usually reduced to two. The two species found at high salinities show some variation in different parts of the world, but generally include species of Brachionus and Hexarthra.
There is a general tendency for the number of rotifer species in a crater lake to increase with increasing vegetation, at least up to the stage where there is a dense, zoned vegetation, and before a complete mosaic of vegetation covers the lake.     

Additions and corrections to the check list of the Noctuoidea (Insecta, Lepidoptera) of North America north of Mexico

A total of 115 additions and corrections are listed and discussed for the check list of the Noctuoidea of North America north of Mexico published in 2010. Thirty-two of these are changes in authorship and/or date of publication or spelling. Taxonomic changes are 33 new or revised synonymies, three new combinations, and six revisions in status from synonymy to valid species.     

New species of Dennstaedtia (Filicales: Dennstaedtiaceae) to Mexico

Dennstaedtia gracilis A. Rojas et Tejero (Dennstaedtiaceae) is herein described and illustrated as a new species endemic to Mexico. Its belongs to the group of winged adaxial secondary costae species but it differs by the combination of characters as smaller fronds, deltate pinnules and lobed segment apex.     

Association between Plant Canopies and the Spatial Patterns of Infiltration in Shrubland and Grassland of the Chihuahuan Desert,New Mexico

Shrubs have invaded extensive areas of grassland in the southwestern United States. The zones of nutrient-rich soil found beneath plant canopies, referred to as “islands of fertility,” are more intense and spaced farther apart in shrubland than in grassland. This difference in the spatial pattern of soil nutrients may reinforce shrub invasion. Changes in water availability in the soil could also influence shrub invasion. Here we compare the spatial patterns of infiltration, defined as the total equivalent water depth entering the soil following individual rainfall events or summed over many events, at adjacent grass- and shrub-dominated sites in the Sevilleta National Wildlife Refuge. We use two infiltration data sets. First, following four rainfall events, we measured soil moisture and wetting front depth at 10-cm intervals along 24-m transects. We estimate infiltration from these data. Second, we use vertical arrays of soil moisture probes to compare infiltration between adjacent canopies and interspaces following 31 storms. In both the grassland and shrubland, infiltration is typically greater beneath plant canopies than beneath interspaces. Canopies are oases where soil moisture is higher than in the surrounding areas. However, infiltration is not greater beneath canopies when surface runoff is limited. In the shrubland, the canopy–interspace infiltration ratio increases as storm size, and therefore runoff, increases. This relationship also exists in the grassland, but it is not as strong or clear. The magnitude of spatial variability of infiltration is similar in shrubland and grassland. In addition, the distance over which infiltration is correlated is approximately 50 cm in both environments. Most of the spatial variability exists between the stem and canopy margin in the shrubland and straddling the canopy margin in the grassland. The most notable difference is that subcanopy oases are spread farther apart in the shrubland because canopies are separated by larger interspaces in this environment. Received 30 October 2001; accepted 1 August 2002.