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Thermal regimes of aquatic ecosystems are predicted to change as climate warming progresses over the next century, with high-latitude and high-elevation regions predicted to be particularly impacted. Here, we have modelled alpine stream water temperatures from air temperature data and used future predicted air temperature trajectories (representative concentration pathway [rcp] 4.5 and 8.5) to predict future water temperatures. Modelled stream water temperatures have been used to calculate cumulative degree days (CDDs) under current and future climate conditions. These calculations show that degree days will accumulate more rapidly under the future climate scenarios, and with a stronger effect for higher CDD values (e.g., rcp 4.5: 18-28 days earlier [CDD = 500]; 42-55 days earlier [CDD = 2000]). Changes to the time to achieve specific CDDs may have profound and unexpected consequences for alpine ecosystems. Our calculations show that while the effect of increased CDDs may be relatively small for organisms that emerge in spring-summer, the effects for organisms emerging in late summer-autumn may be substantial. For these organisms, the air temperatures experienced upon emergence could reach 9°C (rcp 4.5) or 12°C (rcp 8.5) higher than under current climate conditions, likely impacting on the metabolism of adults, the availability of resources, including food and suitable oviposition habitat, and reproductive success. Given that the movement of aquatic fauna to the terrestrial environment represents an important flux of energy and nutrients, differential changes in the time periods to achieve CDDs for aquatic and terrestrial fauna may de-couple existing predator-prey interactions., (Global Change Biology© 2024 The Author(s). Global Change Biology published by John Wiley & Sons Ltd.)

The twentieth anniversary of the first issue of Zootaxa (De Moraes Freire, 2001) provides an appropriate opportunity to reflect on some trends in global Ephemeroptera taxonomy publishing over the last two decades, with a focus on the description of new species and the outsized role of the journals Zootaxa and ZooKeys, in particular. Detailed reviews of world Ephemeroptera knowledge up to about 2000 were collected in a series of nine papers from a symposium on the subject, published together in the proceedings of the ninth International Conference on Ephemeroptera (Domínguez 2001). Domínguez Dos Santos (2014) provided updates and analysis for South America up to the year 2012. More recent detailed accounts of regional and taxonomic diversity, and other aspects of mayfly biology and ecology, were reviewed by Jacobus et al. (2019), while Ogden et al. (2019) discussed current issues involving higher classification.

The mining of gold can lead to toxic metals such as mercury (Hg) contaminating watercourses as by-products. The Reedy Creek sub-catchment, in northeast Victoria, Australia, was mined for gold in the 1850s. In 1998, samples were taken from six watercourses to measure any remaining toxic metal contamination in sediments and surface waters from two creeks with no previous gold mining (controls) and four that were mined. Although mean concentrations of Hg (measured using an ICP-OES) in sediments were below worldwide background levels, individual sites along Reedy Creek had slightly elevated Hg concentrations. In contrast, the Hg concentrations in the surface waters were above background levels. Temporal fluxes of very high Hg concentrations in the surface waters during periods of first flow and flood events revealed that Hg concentrations in the surface waters may, at certain times of the year, exceed all Australian and New Zealand Environment and Conservation Council (National Water Quality Management Strategy. Australian Water Quality Guidelines for Fresh and Marine Waters, ANZECC, 2000) guidelines for water use and the protection of the aquatic ecosystem., (Copyright 2004 Elsevier Ltd.)

The handedness theory of Yeo and Gangestad (1993) posits that moderate right-handedness is the modal manifestation of genetic handedness and that ''developmental instability'' produces deviations from modal handedness. It is also suggested (1) that sinistral parents may produce fewer offspring than do dextral parents; and (2) that sinistral mothers may be more prone to miscarriages than are dextral mothers. In line with these hypotheses, Gangestad et al. (1996) reported that a human leukocyte antigen (B8) was related to both left-handedness and to reduced offspring number in their study. They also found that left-handedness was related to the human leukocyte antigen DR3, and Yeo and Gangestad (1998) noted that this antigen has been found by Christiansen et al. (1996) to be associated with an increased risk of spontaneous abortion in women. We assessed the first hypothesis through a study of the family sizes of 2083 families with two right-handed parents and 502 families having one or more left-handed parents; we assessed the second hypothesis from miscarriage history data supplied by 300 dextral and 52 sinistral mothers. Results supported the developmental instability theory with respect to the hypothesis regarding family size, but not with respect to the hypothesis regarding miscarriage-proneness.

Mothers supplied information on the handedness of a total of 1079 children (238 left handed, 841 right handed), and also reported information on the handedness of the biological parents, parental ages when each child was born, parity, and birth complications. A MANOVA, employing offspring handedness and parental handedness (presence versus absence of at least one left handed) as the bases of classification, and parity, maternal age, paternal age, and a birth stress composite score as dependent measures, was applied to the data of female and male offspring separately. For females, there was a significant multivariate effect for handedness, but no effect of parental handedness nor any interaction of the handedness and parental handedness factors. Univariate ANOVAs, following the multivariate analysis, showed significant effects of handedness for the maternal age and parity measures, but not for paternal age or birth stress composite score. The analysis for males showed no significant multivariate or univariate effects. The data suggest, that in the absence of high risk parity and maternal age over 32, only about 7.8% of females are left handed. This implies that as many as 29% or so of female left handers may owe their sinistrality to factors associated with high risk parity and maternal ages over 32.