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531.
Alejandro Ibáñez Alfonso Marzal Pilar López José Martín 《Behavioral ecology and sociobiology》2014,68(12):2005-2012
Assessment of the fighting ability of potential opponents is an essential skill to minimize the costs of agonistic interactions between males. Previous research showed that chemical cues released in the water by male turtles may convey information about body size, which is important for intrasexual competition. However, the mechanistic basis of such chemical signaling of body size remains poorly understood. Here, we aimed to experimentally examine whether the release of chemosignals is quantitatively or qualitatively dependent on body size in male Spanish terrapins Mauremys leprosa. We compared the time that turtles spent in a pool with clean water versus water containing chemical stimuli of conspecific males of different body sizes at two different concentrations (“diluted” or “undiluted”). Male terrapins avoided water with chemicals secreted by relatively larger males when these chemicals were undiluted, but not after the chemical stimuli were diluted. In contrast, male terrapins did not avoid chemicals of relatively smaller males in any treatment. Thus, male M. leprosa may assess the size of their rivals on the basis of the concentration or the amounts of their chemical cues released into the water and consequently avoid occupying these ponds with higher concentrations of chemicals. This study gives important hints about the mechanism of chemical signaling in freshwater turtles and demonstrates that male turtles may discriminate different concentrations of chemosignals of conspecifics and modify their behavior accordingly. Likewise, our results support the notion that relative body size is a key factor during male interactions in Spanish terrapins. 相似文献
532.
533.
Jeffrey O. Hanson Ana Veríssimo Guillermo Velo-Antón Adam Marques Miguel Camacho-Sanchez Íñigo Martínez-Solano Helena Gonçalves Fernando Sequeira Hugh P. Possingham Silvia B. Carvalho 《Conservation biology》2021,35(2):634-642
Protected-area systems should conserve intraspecific genetic diversity. Because genetic data require resources to obtain, several approaches have been proposed for generating plans for protected-area systems (prioritizations) when genetic data are not available. Yet such surrogate-based approaches remain poorly tested. We evaluated the effectiveness of potential surrogate-based approaches based on microsatellite genetic data collected across the Iberian Peninsula for 7 amphibian and 3 reptilian species. Long-term environmental suitability did not effectively represent sites containing high genetic diversity (allelic richness). Prioritizations based on long-term environmental suitability had similar performance to random prioritizations. Geographic distances and resistance distances based on contemporary environmental suitability were not always effective surrogates for identification of combinations of sites that contain individuals with different genetic compositions. Our results demonstrate that population genetic data based on commonly used neutral markers can inform prioritizations, and we could not find an adequate substitute. Conservation planners need to weigh the potential benefits of genetic data against their acquisition costs. 相似文献
534.
535.
María Elizabeth Barroeta-Hlusicka Joaquín Buitrago Martín Rada Ricardo Pérez 《Journal of Coastal Conservation》2012,16(1):65-76
Protected areas are the core of efforts to conserve biological diversity and zoning uses, and they are used as a tool for
their management. Global Positioning Systems (GPS) and Geographic Information System (GIS) have been used to evaluate conflicts
between approved uses and actual uses in La Restinga Lagoon National Park in Venezuela (LRLNP). The park (188.6 km2), covers various ecosystems such as coastal lagoons, marine waters and xerophytic vegetation, it is visited by up to 260,000
people visit per year. A GIS, using a base map compiled from 1:25,000 maps was developed. Natural cover was mapped from LANDSAT
VII TM images, orthophotomaps and aerial photographs. Spatial use data was collected by field GPS location of any use inside
the park during 2 years. Thematic vector maps for each land cover, zoning area, and observed use were created. Maps of zoning
and uses were overlapped and new maps for each use-zoning crossing were created. The park contain nine different zoning areas
wherein 28 different uses were identified, 18 of them were direct consumptive and non-consumptive uses, occurring on 54% of
the park. Tourism transit areas were the most used zones. More than 5,000 people use the park during a high season day. Superimposition
of zoning maps with actual use data produced 13 uses taking place in not allowed areas (46% of park area). Most common prohibited
use was commercial net fishing, occurring in nearly 40% of the park area. Therefore, identifying human use conflicts and its
geographical distribution is a key issue to improve Management Plans as well as identifying hot sites. The GPS-GIS methodology
presented here allows Park Rangers to select those areas which could benefit from enhanced supervision with the limited budget
available. 相似文献
536.
Multiple traits may either signal different characteristics of a male or be redundant. These multiple signals may convey different
messages if they are intended for different receivers (e.g., male or females) that have different interests. We examined the
functions of multiple colorful visual traits of male Schreiber’s green lizard (Lacerta schreiberi). Results showed that interindividual variation in the characteristics of coloration of males can be related to variation
in morphology, health state, dominance status, and pairing status, but that different relationships were found for each color
signal. For example, dominant males had brighter “blue” throat and with higher values of ultraviolet (UV) and bluish coloration
and darker and greenish dorsal coloration than subordinate males. Health state was also reflected in coloration; males with
a higher immune response had “blue” throats with lower amounts of UV coloration, but had “yellow” chests with higher amounts
of UV coloration. Males found guarding females also differed in coloration from males found alone. These data suggest that
characteristics of coloration of the different multiple signals may reveal different messages for different receivers, either
male or female conspecifics. The development of the different signals, based on different morphological and physiological
mechanisms and trade-offs, may allow signal reliability of multiple colorful traits in different social contexts. 相似文献
537.
Compositional analysis of topsoil metals and its associations with cancer mortality using spatial misaligned data 总被引:1,自引:0,他引:1
Gonzalo López-Abente Juan Locutura-Rupérez Pablo Fernández-Navarro Iván Martín-Méndez Alejandro Bel-Lan Olivier Núñez 《Environmental geochemistry and health》2018,40(1):283-294
The presence of toxic metals in soil per se, and in soil impacted by mining, industry, agriculture and urbanisation in particular, is a major concern for both human health and ecotoxicology. The dual aim of this study was: to ascertain whether topsoil composition could influence the spatial distribution of mortality due to different types of cancer and to identify possible errors committed by epidemiological studies which analyse soil composition data as a closed number system. We conducted an ecological cancer mortality study, covering 861,440 cancer deaths (27 cancer sites) in 7917 Spanish mainland towns, from 1999 to 2008. Topsoil levels of Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined by ICP-MS at 13,317 sampling points. We transformed the topsoil data in two ways, i.e. log transformation and centred logratio transformation. Principal factor analysis was performed to obtain independent latent factors for the transformed variables. To estimate the effect on mortality of topsoil factor loadings, we fitted Besag, York and Mollié models embedded in geostatistical-spatial models. This model included soil sample locations and town centroids (non-aligned data), fitted using the integrated nested Laplace approximation (INLA) as a tool for Bayesian inference and stochastic partial differential equations (SPDE). All results were adjusted for socio-demographic variables. The results indicated that soil composition could have an influence on the spatial distribution and mortality patterns of cancer. The analysis adjusted for socio-demographic variables showed excess male mortality due to digestive system tumours in areas with soils containing higher Cd, Pb, Zn, Mn and Cu concentrations, bladder cancer in areas with soils containing higher Cd concentrations, and brain cancer in areas with soils containing As. In both sexes, cancer of oesophagus was associated with soils containing a higher lead content, while lung cancer was associated with soils containing a higher copper content. Stress should be laid on the importance of taking into account the compositional nature of the data in this type of analysis. 相似文献
538.
Are functional traits good predictors of demographic rates? Evidence from five neotropical forests 总被引:5,自引:0,他引:5
Poorter L Wright SJ Paz H Ackerly DD Condit R Ibarra-Manríquez G Harms KE Licona JC Martínez-Ramos M Mazer SJ Muller-Landau HC Peña-Claros M Webb CO Wright IJ 《Ecology》2008,89(7):1908-1920
A central goal of comparative plant ecology is to understand how functional traits vary among species and to what extent this variation has adaptive value. Here we evaluate relationships between four functional traits (seed volume, specific leaf area, wood density, and adult stature) and two demographic attributes (diameter growth and tree mortality) for large trees of 240 tree species from five Neotropical forests. We evaluate how these key functional traits are related to survival and growth and whether similar relationships between traits and demography hold across different tropical forests. There was a tendency for a trade-off between growth and survival across rain forest tree species. Wood density, seed volume, and adult stature were significant predictors of growth and/or mortality. Both growth and mortality rates declined with an increase in wood density. This is consistent with greater construction costs and greater resistance to stem damage for denser wood. Growth and mortality rates also declined as seed volume increased. This is consistent with an adaptive syndrome in which species tolerant of low resource availability (in this case shade-tolerant species) have large seeds to establish successfully and low inherent growth and mortality rates. Growth increased and mortality decreased with an increase in adult stature, because taller species have a greater access to light and longer life spans. Specific leaf area was, surprisingly, only modestly informative for the performance of large trees and had ambiguous relationships with growth and survival. Single traits accounted for 9-55% of the interspecific variation in growth and mortality rates at individual sites. Significant correlations with demographic rates tended to be similar across forests and for phylogenetically independent contrasts as well as for cross-species analyses that treated each species as an independent observation. In combination, the morphological traits explained 41% of the variation in growth rate and 54% of the variation in mortality rate, with wood density being the best predictor of growth and mortality. Relationships between functional traits and demographic rates were statistically similar across a wide range of Neotropical forests. The consistency of these results strongly suggests that tropical rain forest species face similar trade-offs in different sites and converge on similar sets of solutions. 相似文献
539.
J. A. González-Pérez J. R. de Andrés L. Clemente J. A. Martín F. J. González-Vila 《Environmental Chemistry Letters》2008,6(1):41-46
Here we show that heavy metal geoaccumulation is apparent in the Tinto and Odiel estuary and, at a lower magnitude, in off-shore
sediments. Values above probable effects level (PEL) are recorded for As, Cu, Hg, Pb and Zn in the Tinto and Odiel estuary,
for As and Hg in the associated off-shore sediments and for As in the Guadiana River. Significant correlations were found
between total organic carbon (TOC) and Cr, Cu, Ni and Zn in the Tinto and Odiel estuary, and Cr, Cu, Ni, Pb, Hg and As in
the Guadiana River. PCA analysis differentiated the three studied locations. 相似文献
540.
The growing gray seal population in the Baltic Sea has led to increased conflicts with fisheries. Despite limited data on gray seal ecology, management measures, such as culling, have been implemented recently. We studied movements and site fidelity of Baltic gray seals using mark-recapture analysis based on photographic identification of individuals (photo-id). Seals were photographed at the major summer haul-out sites. Profile photographs of the head and neck were matched using purpose-written software to generate a database of capture histories from 1995-2000. The haul-outs were grouped into seven areas. Darroch's method (20) for a two-sample capture-recapture census was adapted to estimate rates of movement between the areas. The majority of seals were estimated to remain within the same area, suggesting that Baltic gray seals exhibit a high degree of site fidelity during the summer, and that fidelity to a site lasts for more than one season. 相似文献