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Mexus Education is an education solutions provider located in Mumbai, India. The company works in the K-12 segment, in collaboration with educators, learners, academicians and administrators to deliver learner-driven content through appropriate interactive technology. Multimedia usage includes the use of films, graphic novels, games and hands-on kits. Wikipedia.

Castellanos-Acuna D.,Universidad Michoacana de San Nicolas de Hidalgo | Lindig-Cisneros R.,National Autonomous University of Mexico | Lindig-Cisneros R.,Mexus | Saenz-Romero C.,Universidad Michoacana de San Nicolas de Hidalgo | And 2 more authors.
Ecosphere | Year: 2015

Since shifts in altitudinal range are expected in response to climate change, we explored the effect on survivorship and growth of moving populations of three Mexican pine species (Pinus devoniana, P. leiophylla and P. pseudostrobus) to higher altitude, aiming to realign the populations to projected future climates in an experimental assisted migration. Twelve populations were collected across an altitudinal gradient (1650-2520 m above sea level [asl]) in a mountainous zone in the central-west region of the Mexican Trans-Volcanic Belt, and were planted in common garden tests at three forest sites of different altitudes (low: 2110, medium: 2422 and upper: 2746 m asl). Climate was estimated using a spline climatic model at the seed source and test sites and also measured using in situ data loggers. Survivorship and seedling height were evaluated in the field during the second and third growing seasons. Results were analyzed using mixed models to include the effect of climatic transfer distances (difference in climate between seed source and test site). Significant differences were found in seedling growth among Pinus devoniana, P. pseudostrobus and P. leiophylla, and among populations within the former two species. These were associated primarily with climatic transfer distances of extreme temperatures (minimum temperature in the coldest month and mean temperature in the warmest month). There was a significant decrease in growth in P. devoniana when the transfer exceeded 650 m of upward altitudinal shift or a reduction of 1.58C with transfer to colder sites. There was also a decrease of growth in P. pseudostrobus when transfer exceeded 400 m of upward altitudinal shift or 1.58C, with a significant decrease in survivorship. Pinus leiophylla, however, exhibited similar growth at all altitudes tested, probably due to phenotypic plasticity. Although further research is required with field tests using commercial spacing and trees of older ages, the results suggest that an assisted upwards migration of 300 m in altitude, in order to approach a realignment of the populations to the climate projected for the decade centered around the year 2030, appears to be a viable strategy with which to accommodate the effects of climate change. © 2015 Castellanos-Acuña et al. Source

Erisman B.,University of Texas at Austin | Mascarenas-Osorio I.,Centro Para La Biodiversidad Marina Y La Conservacion Ac | Lopez-Sagastegui C.,Mexus | Moreno-Baez M.,University of California at San Diego | And 2 more authors.
Fisheries Research | Year: 2015

We engaged in collaborative research with two small-scale fishing communities inside the Upper Gulf of California Biosphere Reserve in Mexico, San Felipe (SF) and El Golfo de Santa Clara (GSC), to test how well the geographic heterogeneity of fishing activities within the reserve coincided with current regulations. We compared the two communities in terms of catch composition, fishing effort, ex-vessel prices and revenues, seasonal patterns in fishing activities in relation to the reproductive seasons of target species, and spatial patterns of fishing in relation to managed zones within the reserve. The top four species (Cynoscion othonopterus, Micropogonias megalops, Scomberomorus concolor, Litopenaeus stylirostris) in terms of relative effort, catch, and revenues were the same for both communities but overall fisheries production, effort, and revenues were higher in GSC than SF for these species. Fishing activities in GSC followed a predictable annual cycle that began with L. stylirostris and were followed sequentially by the harvesting of C. othonopterus, M. megalops, and S. concolor during their respective spawning seasons, which were associated with seasonal variations in ex-vessel prices. Conversely, catch and revenues in SF were more diversified, less dependent on those four species, less seasonal, and did not show seasonal variations in prices. Interactions between fisheries and managed zones also differed such that SF interacted mainly with the southwest portion of the vaquita (Phocoena sinus) refuge, whereas GSC fished over a larger area and interacted mainly with the northeast portion of the vaquita refuge and the no-take zone. Our results indicate the two communities differ markedly in their socio-economic dependence on fisheries, their spatio-temporal patterns of fishing, their use of and impacts on species, coastal ecosystems and managed areas, and how different regulations may affect livelihoods. Regional management and conservation efforts should account for these differences to ensure the protection of endangered species and to sustain ecosystem services that maintain livelihoods and healthy coastal ecosystems. This study provides further evidence of the ability of collaborative research between scientists and fishers to produce robust and fine-scale fisheries and biological information that improves the collective knowledge and management of small-scale fisheries within marine protected areas. © 2014 Elsevier B.V. Source

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Velarde E.,University of Veracruz | Wilder B.T.,University of California at Riverside | Felger R.S.,University of Arizona | Ezcurra E.,University of California at Riverside | Ezcurra E.,Mexus
Botanical Sciences | Year: 2014

Isla Rasa, a small (0.68 km2) but globally important seabird island in the Gulf of California, has a fl ora of only 14 vascular plant species found in three vegetation zones. Signifi cant physical alteration of the island's surface and the introduction of non-native rodents, eradicated in 1995, add restoration ecology to the remarkable biology of the island. Over a century of botanical collections and observations record a consistently depauperate fl ora, best understood in the context of extreme aridity, isolation, and elevated levels of nitrogen and phosphorus from bird guano. The shaping factor of guano on the dearth of floristic diversity illustrates close connection between marine and terrestrial ecosystems in the Gulf of California. El Niño events that trigger collapses in marine productivity and crashes in seabird reproduction bring above-average winter rainfall pulses and rapidplantgrowth.Two new island records are reported (Rhizophora mangle and Viscainoa geniculata). Matched photographs show signifi cant increase in the cholla cactus (Cylindropuntia fulgida) since 1971. Baseline knowledge of seabird breeding ecology and theflora of the island position Isla Rasa as a preeminent locality to study and monitor the ecological dynamics of a desert island in the context of restoration ecology and global environmental change. Source

Wilder B.T.,University of California at Riverside | Betancourt J.L.,U.S. Geological Survey | Epps C.W.,Oregon State University | Crowhurst R.S.,Oregon State University | And 3 more authors.
PLoS ONE | Year: 2014

Bighorn sheep ( Ovis canadensis) were not known to live on Tiburón Island, the largest island in the Gulf of California and Mexico, prior to the surprisingly successful introduction of 20 individuals as a conservation measure in 1975. Today, a stable island population of ∼500 sheep supports limited big game hunting and restocking of depleted areas on the Mexican mainland. We discovered fossil dung morphologically similar to that of bighorn sheep in a dung mat deposit from Mojet Cave, in the mountains of Tiburón Island. To determine the origin of this cave deposit we compared pellet shape to fecal pellets of other large mammals, and extracted DNA to sequence mitochondrial DNA fragments at the 12S ribosomal RNA and control regions. The fossil dung was 14C-dated to 1476-1632 calendar years before present and was confirmed as bighorn sheep by morphological and ancient DNA (aDNA) analysis. 12S sequences closely or exactly matched known bighorn sheep sequences; control region sequences exactly matched a haplotype described in desert bighorn sheep populations in southwest Arizona and southern California and showed subtle differentiation from the extant Tiburón population. Native desert bighorn sheep previously colonized this land-bridge island, most likely during the Pleistocene, when lower sea levels connected Tiburón to the mainland. They were extirpated sometime in the last ∼1500 years, probably due to inherent dynamics of isolated populations, prolonged drought, and (or) human overkill. The reintroduced population is vulnerable to similar extinction risks. The discovery presented here refutes conventional wisdom that bighorn sheep are not native to Tiburón Island, and establishes its recent introduction as an example of unintentional rewilding, defined here as the introduction of a species without knowledge that it was once native and has since gone locally extinct. Source

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