Genetic mating system and timing of extra-pair fertilizations in the Kentish plover

It is still unclear why females in many bird species pursue extra-pair copulations. Current hypotheses focus mainly on indirect benefits such as obtaining particular good genes for their offspring or maximizing genetic compatibility between themselves and the father of their offspring. Supporting the latter, a recent study of shorebirds suggests that extra-pair matings may function to avoid the negative effects of genetic similarity between mates. Here, we further investigate genetic parentage in the Kentish plover, Charadrius alexandrinus, a shorebird with a highly variable social mating system. DNA fingerprinting revealed that most pairs were genetically monogamous: 7.9% of the broods (7/89) contained extra-pair young, comprising 3.9% of all chicks (9/229). These cases represented, however, three alternative reproductive behaviors: extra-pair paternity, quasi-parasitism (extra-pair maternity) and intraspecific brood parasitism. This is the first study showing the occurrence of all three behaviors in one shorebird species. We also found that extra-pair fertilizations (extra-pair paternity and quasi-parasitism) were more frequent later in the breeding season. There was no consistent relationship between genetic similarity of mates and laying date; the pattern, as well as the degree of genetic similarity, differed among breeding sites within the study population.Communicated by M. Webster     

Walking on insect paths? Early ommatidial development in the compound eye of the ancestral crustacean, Triops cancriformis

 Ommatidia (the compound eye's functional units) in insects are formed by the recruitment of undifferentiated cells under the control of signalling factors. During this process, a sequence of "preclusters" composed of specifically arranged precursor cells is followed. In the growth zone of the eye of Triops, an ancestral crustacean, we observed a patterning process that corresponds well with that of insects. In both taxa, clusters with arc-like, five-cell and eight-cell patterns are found, and the sequence in which the photoreceptor or R-cells of each ommatidium become identifiable is basically the same. The first to appear are R8-like and R2/5-like cells, second are R3/4-like, and third are R1/6- and R7-like cells (if the fly's cell-numbering system is used). Thus, the morphogenetic steps during which the cell identities and the cellular architecture of the ommatidia develop appear to be conserved between these arthropod groups. Furthermore, the individual cells and cell pairs which build an insect ommatidium seem to have their homologues in crustaceans. In the evolution of developmental processes, intercellular recruitment seems to be a mechanism operating on the level of single cells even in distantly related species. Received: 12 May 2000 / Accepted in revised form: 17 May 2000     

Floral colour change in <Emphasis Type="Italic">Byrsonima variabilis</Emphasis> (Malpighiaceae) as a visual cue for pollen but not oil foraging by oil-collecting bees

Pollinators search for multiple flora resources throughout their life cycle. Most studies, however, only assess how bees discriminate floral cues in the context of nectar foraging. In the present study, we sought to elucidate whether oil-collecting bees discriminate flowers of Byrsonima variabilis (Malpighiaceae) with petals of different colours when foraging for pollen or oil. As the colour of the standard petal changes during anthesis, we characterised the spectral reflectance patterns of flowers throughout anthesis and modelled chromatic perceptual space to determine how these colour patterns are perceived by bees. Through the quantification of flower pollen in the different phases, we found that the colour of the standard petal is an honest cue of the presence of pollen. Centridine bees preferentially visited flowers with a yellow (bee’s green) colour when searching for pollen, but indiscriminately visited flowers with different petal colours when searching for floral oil. We suggest that standard petals, in the species studied and others of the genus, like nectar guides, act as pollen guides, which oil-collecting females use to detect pollen-rich flowers. Moreover, they use different floral clues during foraging for different resources in the same host plant.     

Publicly available datasets on thallium (Tl) in the environment—a comment on <Emphasis Type="Italic">“Presence of thallium in the environment: sources of contaminations,distribution and monitoring methods”</Emphasis> by Bozena Karbowska,Environ Monit Assess (2016) 188:640 (DOI 10.1007/s10661-016-5647-y)

This comment highlights a whole series of datasets on thallium concentrations in the environment that were overlooked in the recent review by Karbowska, Environmental Monitoring and Assessment, 188, 640, 2016 in this journal. Geochemical surveys carried out over the last few decades all over the world at various scales and using different sampling media have reported the concentration of thallium (and dozens more elements) in tens of thousands of samples. These datasets provide a ‘real-world’ foundation upon which source apportionment investigations can be based, monitoring programs devised and modelling studies designed. Furthermore, this comment also draws attention to two global geochemical mapping initiatives that should be of interest to environmental scientists.     

Emissions from the copper–nickel industry on the Kola Peninsula and at Noril'sk,Russia

Published estimates for base metal emissions from the copper–nickel industry on the Kola Peninsula are re-examined in the light of (a) chemical data on the composition of the ores; (b) official emission figures for 1994; and (c) modelled emissions based on dry and wet deposition estimates derived from data for snow and rain samples collected in 1994. The modelled emissions, official emission figures and chemical data are mutually compatible for Ni, Cu and Co and show that previously published figures underestimated the emissions of the major elements, Ni and Cu (though within the same order of magnitude) and overestimated the emissions of As, Pb, Sb and Zn by up to several orders of magnitude, in some cases exceeding the calculated total input to the plants. Published estimates have neglected information on the nature and chemistry of the ores processed in metallurgical industries in the Noril'sk area of Siberia and the Urals. Revised emission estimates for 1994, using knowledge of the chemistry of the ores, are proposed: taken with published information on total emissions up to 2000 these data give an indication of emission levels in more recent years.     

The influence on the radioxenon background during the temporary suspension of operations of three major medical isotope production facilities in the Northern Hemisphere and during the start-up of another facility in the Southern Hemisphere

Medical isotope production facilities (MIPF) have recently been identified to emit the major part of the environmental radioxenon measured at many globally distributed monitoring sites deployed to strengthen the radionuclide component of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) verification regime. Efforts to raise a global radioxenon emission inventory revealed that the yearly global total emission from MIPF’s is around 15 times higher than the total radioxenon emission from nuclear power plants (NPP's).Given that situation, from mid 2008 until early 2009 two out of the ordinary hemisphere-specific events occured:1) In the Northern hemisphere, a joint temporary suspension of operations of the three largest MIPF's made it possible to quantify the effects of the emissions related to NPP’s. The average activity concentrations of ¹³³Xe measured at a monitoring station close to Freiburg, Germany, went down significantly from 4.5 ± 0.5 mBq/m³ to 1.1 ± 0.1 mBq/m³ and in Stockholm, Sweden, from 2.0 ± 0.4 mBq/m³ to 1.05 ± 0.15 mBq/m³.2) In the Southern hemisphere the only radioxenon-emitting MIPF in Australia started up test production in late November 2008. During eight test runs, up to 6.2 ± 0.2 mBq/m³ of ¹³³Xe was measured at the station in Melbourne, 700 km south-west from the facility, where no radioxenon had been observed before, originating from the isotopic production process.This paper clearly confirms the hypothesis that medical isotope production facility are at present the major emitters of radioxenon to the atmosphere. Suspension of operations of these facilities indicates the scale of their normal contribution to the European radioxenon background, which decreased two to four fold. This also gives a unique opportunity to detect and investigate the influence of other local and long distance sources on the radioxenon background. Finally the opposing effect was studied: the contribution of the start-up of a renewed radiopharmaceutical facility to the build up of a radioxenon background across Australia and the Southern hemisphere.     

Spatial surrogates for the disaggregation of CORINAIR emission inventories

CORINAIR atmospheric emission inventories are frequently used input data for air quality models with a domain situated in Europe. In CORINAIR emission inventories, sources are broken down over 11 major source categories. This paper presents spatial surrogates for the disaggregation of CORINAIR atmospheric emission inventories for input of air pollutants and particulate matter to grid or polygon based air quality model domains inside Europe. The basis for the disaggregation model was the CLC2000 land cover data to which statistical weights were added. Weights were population census data for residential emissions, employment statistics for agricultural and industrial area emissions, livestock statistics for ammonia emissions and annual aircraft movements for emissions realized by air transport. Additional road and off-road network information was used to disaggregate emissions realized by traffic. A comparison of top down produced emission estimates with spatially resolved national emission data for The Netherlands and the United Kingdom gave confidence in the present spatial surrogates as a tool for the top down production of atmospheric emission maps. Explained variance at a spatial resolution of 5 km was >70% for CO, NMVOC and NO_x, >60% for PM10 and almost 50% for SO₂.     

Validation of Urban Emission Inventories

Two emission validation methods are presented. The first method focuses on the precision of the emission factors and the accuracy of modelled traffic flows. Emission factors derived from the COPERT II methodology are compared with on-board emission measurements and modelled traffic flow rates are compared with observations. The second validation method focuses on the completeness of the inventory, i.e. coverage of all sources. The method compares measured pollutant fluxes in the urban plume with the downwind transported and dispersed emissions integrated over plume width and mixing height. Both methods seem to indicate that traffic emission factors used in the urban emission inventories show large uncertainties. Besides the lack of measurement precision this is mainly induced by external influence factors like driving behaviour and vehicle maintenance.     

Clean development mechanism: an incentive for waste management projects?

The Clean Development Mechanism (CDM) was introduced by the Kyoto Protocol to provide a financial incentive to establish project activities in developing countries for reducing greenhouse gas emissions while also fostering sustainable development. This article shows that waste management project activities play an important role in achieving the aims of the CDM. It describes how these activities have to prove additionality, how the emission reductions must be calculated and monitored in order to be eligible and in order to lead to Certified Emission Reductions (CERs). The article further provides an analysis about the various challenges that are involved in applying the CDM scheme to waste management project activities, which require a new specific set of technical skills and regulatory standards.