Characteristics of natural salt licks located in the Colombian Amazon foothills

Salt licks are key places for the ecological dynamics of wildlife communities around the world and are locations where animals develop geophagical behaviours. Geophagy is a method for animals to supplement their diets or facilitate their digestive processes and is related to the health of individuals and populations. This study characterises a series of salt licks located in the Colombian Amazon foothills and describes their structural, mineralogical and physicochemical properties, as well as the fauna that visit these locations. The results are analysed in reference to the geological characteristics of the study area and in relation to the role of the salt lick in the nutritional ecology of the Amazonian fauna. Located in the study area are two types of salt licks that are significantly different in composition. These salt licks are located in an area where young geological materials have been exposed. The characteristics of the salt licks supports the hypothesis that they are used to solve nutritional problems that result from herbivorous diets. The clear importance of salt licks in the ecology of several Amazonian animal species emphasises the need to prioritise conservation areas by maximising the complementarities of salt lick sites.     

Changes in maternal blood concentrations of selected essential and toxic elements during and after pregnancy

The objective of this study was to investigate changes in the levels of toxic and essential elements in maternal blood during pregnancy and subsequently. A subset of 211 pregnant women from the North Norwegian Mother-and-Child Study was included. Blood samples were collected during the 2(nd) trimester (P1) and postpartum (day 3, P2; and 6 weeks, P3) in different regions of northern Norway, and were analyzed for a suite of 10 selected elements. The latter feature three general but distinct concentration patterns across the three collection periods, namely: progressive increase [Group 1: As, Cd (non-smokers only), Mn, Pb and Zn]; V-shaped, with a minimum at P2 [Group 2: Cd (smokers), Hg, Mo and Se]; and downward V, with a maximum at P2 [Group 3: Co and Cu]. These trends are interpreted in the context of underlying metabolic, hematological and physiological changes that occur in mothers, as well the biochemistry and accumulation preferences of these elements within the whole blood compartment and breast milk. Implications for biomonitoring strategies are discussed. In a multivariable analysis of the P1 data, fish consumption was a robust positive predictor for Hg (p < 0.02), As (p < 0.01) and Se (p ≤ 0.001) blood concentrations, multivitamin intake for Se (p < 0.001), and parity for Co (p < 0.002); age reached significance only for Hg (p < 0.001). An inverse association was observed between parity and Hg (p < 0.05). For the other elements, predictor patterns were not evident.     

Darwin's special difficulty: the evolution of “neuter insects” and current theory

In the Origin of Species, Darwin discussed several challenges that worker insects presented to his theory of natural selection. Complex instincts such as building of combs of hexagonal cells were one problem and were explained by showing plausible intermediate stages. A more serious challenge was posed by the multiple worker castes seen in many ants. How could sterile individuals continue to evolve? A careful reading of the Origin suggests that Darwin was not primarily concerned by the evolution of worker sterility itself, which he considered a minor difficulty. Some modern commentaries on Darwin and insect workers seem to be cases of present interests interfering with the interpretation of the past. From a modern perspective, the evolution of a worker caste, and its corollary altruism, are evolutionary puzzles inasmuch as natural selection normally favors greater, not lesser, individual reproduction. These puzzles were resolved by Hamilton's theory of inclusive fitness. We now have a good functional understanding of how natural selection can cause both the origin of workers and their elaboration into greater levels of sterility and multiple morphological castes. Mechanistic understanding of morphological castes is also increasing via research into alternative developmental pathways. When the Origin was written, genetics did not exist and it would have been virtually impossible for Darwin to elaborate such ideas. However, the Origin probably addressed the main questions in the minds of Victorian readers in relation to insect workers. Darwin was prescient in having insights with close relationships to modern-day interests and the key principles involved, including kinship and benefits to the colony, even if these are not exact precursors to modern thinking.     

Protected area characteristics that help waterbirds respond to climate warming

Protected area networks help species respond to climate warming. However, the contribution of a site's environmental and conservation-relevant characteristics to these responses is not well understood. We investigated how composition of nonbreeding waterbird communities (97 species) in the European Union Natura 2000 (N2K) network (3018 sites) changed in response to increases in temperature over 25 years in 26 European countries. We measured community reshuffling based on abundance time series collected under the International Waterbird Census relative to N2K sites’ conservation targets, funding, designation period, and management plan status. Waterbird community composition in sites explicitly designated to protect them and with management plans changed more quickly in response to climate warming than in other N2K sites. Temporal community changes were not affected by the designation period despite greater exposure to temperature increase inside late-designated N2K sites. Sites funded under the LIFE program had lower climate-driven community changes than sites that did not received LIFE funding. Our findings imply that efficient conservation policy that helps waterbird communities respond to climate warming is associated with sites specifically managed for waterbirds.     

Numerical Study of Physical and Biogeochemical Processes Controlling Dissolved Oxygen in an Urbanized Subtropical Estuary: Vitória Island Estuarine System,Brazil

Environmental Modeling & Assessment - Subtropical estuaries such as the Vitória Island Estuarine System (VIES), located on the central coast of Brazil, are under strong anthropic pressure....     

Retrospective bioindication of stratospheric ozone and ultraviolet radiation using hydroxycinnamic acid derivatives of herbarium samples of an aquatic liverwort

We analyzed bulk UV absorbance of methanolic extracts and levels of five UV-absorbing compounds (hydroxycinnamic acid derivatives) in 135 herbarium samples of the liverwort Jungermannia exsertifolia subsp. cordifolia from northern Europe. Samples had been collected in 1850–2006 (96% in June–August). Both UV absorbance and compound levels were correlated positively with collection year. p-Coumaroylmalic acid (C1) was the only compound showing a significant (and negative) correlation with stratospheric ozone and UV irradiance in the period that real data of these variables existed. Stratospheric ozone reconstruction (1850–2006) based on C1 showed higher values in June than in July and August, which coincides with the normal monthly variation of ozone. Combining all the data, there was no long-term temporal trend from 1850 to 2006. Reconstructed UV showed higher values in June–July than in August, but again no temporal trend was detected in 1918–2006 using the joint data. This agrees with previous UV reconstructions.     

Amnion rupture sequence in a first trimester missed abortion

We report the diagnosis of amnion rupture sequence made by sonography and fetoscopy during the first trimester of gestation in a case of missed abortion. The investigation revealed a demised fetus with the characteristics of 9 weeks of development. The early fetus had an amnion adhesion at the tip of the nose and strands of amnion wrapped around the terminal phalanges of both feet. No defects in addition to the face and limb involvement were identified. The karyotype was normal: 46,XX. In the reported case, fetoscopy allowed confirmation of the sonographic diagnosis of an amnion rupture sequence in the first trimester of gestation and consequently helped to clarify the cause of abortion in this case of early fetal demise. Copyright © 2001 John Wiley & Sons, Ltd.     

Preimplantation genetic diagnosis of pericentric inversions

Inversions are structural chromosome abnormalities that may be associated with infertility, multiple miscarriage and chromosomally unbalanced offspring. Preimplantation genetic diagnosis (PGD) with subtelomeric probes was used to select for transfer only those embryos that were normal or balanced for three pericentric inversions. In contrast to previous protocols the present procedure allows the detection of unbalanced embryos that might arise from U-recombination in the inverted region. Additionally, aneuploidy screening was carried out in two cases by a second round of fluorescent in situ hybridization (FISH) with centromeric probes. Of the three couples that underwent the procedure one became pregnant twice. The first pregnancy delivered a healthy and chromosomally normal baby and the second pregnancy is ongoing with triplets. Copyright © 2001 John Wiley & Sons, Ltd.