39 research outputs found
Design of, and enrollment in, the palliative care communication research initiative: a direct-observation cohort study
The Evolution of a Female Genital Trait Widely Distributed in the Lepidoptera: Comparative Evidence for an Effect of Sexual Coevolution
Sexual coevolution is considered responsible for the evolution of many male genital traits, but its effect on female genital morphology is poorly understood. In many lepidopterans, females become temporarily unreceptive after mating and the length of this refractory period is inversely related to the amount of spermatophore remaining in their genital tracts. Sperm competition can select for males that delay female remating by transferring spermatophores with thick spermatophore envelopes that take more time to be broken. These envelopes could select for signa, sclerotized sharp structures located within the female genital tract, that are used for breaking spermatophores. Thus, this hypothesis predicts that thick spermatophore envelopes and signa evolve in polyandrous species, and that these adaptations are lost when monandry evolves subsequently. Here we test the expected associations between female mating pattern and presence/absence of signa, and review the scant information available on the thickness of spermatophore envelopes.We made a literature review and found information on female mating pattern (monandry/polyandry), presence/absence of signa and phylogenetic position for 37 taxa. We built a phylogenetic supertree for these taxa, mapped both traits on it, and tested for the predicted association by using Pagel's test for correlated evolution. We found that, as predicted by our hypothesis, monandry evolved eight times and in five of them signa were lost; preliminary evidence suggests that at least in two of the three exceptions males imposed monandry on females by means of specially thick spermatophore envelopes. Previously published data on six genera of Papilionidae is in agreement with the predicted associations between mating pattern and the characteristics of spermatophore envelopes and signa.Our results support the hypothesis that signa are a product of sexually antagonistic coevolution with spermatophore envelopes
Tracing potential soil contamination in the historical Solvay soda ash plant area, Jaworzno, Southern Poland
This study of soil conditions was carried out on 30 meadow soil (podzol) samples from the vicinity of the soda ash heap in Jaworzno, supplemented by analyses of 18 samples of waste deposited on the heap. In all samples, the total content of macroelements (Ca and Na) and heavy metals (Cd, Cr, Ni, Pb and Zn) as well as pH were analysed. The element concentrations were measured using inductively coupled plasma optical emission spectrometry (ICP-OES). The materials examined were neutral to ultra-alkaline. Total accumulations (mg kg(−1)) of chemical elements in the soil vary from 130.24 to 14076.67 for Ca, 41.40–926.23 for Na, 0.03–3.34 for Cd, 0.94–103.62 for Cr, 0.94–35.89 for Ni, 3.51–76.47 for Pb and 12.05–279.13 for Zn, whereas quantities of the same elements in the waste samples vary from 171705.13 to 360487.94 for Ca, 517.64–3152.82 for Na, 0.2–9.89 for Cd, 1.16–20.40 for Cr, 1.08–9.79 for Ni, 0.1–146.05 for Pb and 10.26–552.35 for Zn. The vertical distribution of the metals was determined in each soil profile. Despite enrichment of heavy metals in the uppermost horizon on the top of the heap, the results lead to the conclusion that the relation of historical production of soda ash in Jaworzno to current contamination of the local soil environment is insignificant