Mating system affects population performance and extinction risk under environmental challenge

Failure of organisms to adapt to sudden environmental changes may lead to extinction. The type of mating system, by affecting fertility and the strength of sexual selection, may have a major impact on a population's chances to adapt and survive. Here, we use experimental evolution in bulb mites (Rhizoglyphus robini) to examine the effects of the mating system on population performance under environmental change. We demonstrate that populations in which monogamy was enforced suffered a dramatic fitness decline when evolving at an increased temperature, whereas the negative effects of change in a thermal environment were alleviated in polygamous populations. Strikingly, within 17 generations, all monogamous populations experiencing higher temperature went extinct, whereas all polygamous populations survived. Our results show that the mating system may have dramatic effects on the risk of extinction under environmental change

Relative costs and benefits of alternative reproductive phenotypes at different temperatures : genotype-by-environment interactions in a sexually selected trait

Abstract Background The maintenance of considerable genetic variation in sexually selected traits (SSTs) is puzzling given directional selection expected to act on these traits. A possible explanation is the existence of a genotype-by-environment (GxE) interaction for fitness, by which elaborate SSTs are favored in some environments but selected against in others. In the current study, we look for such interactions for fitness-related traits in the bulb mite, a male-dimorphic species with discontinuous expression of a heritable SST in the form of enlarged legs that are used as weapons. Results We show that evolution at 18 °C resulted in populations with a higher prevalence of this SST compared to evolution at 24 °C. We further demonstrate that temperature modified male reproductive success in a way that was consistent with these changes. There was a genotype-by-environment interaction for reproductive success – at 18 °C the relative reproductive success of armored males competing with unarmored ones was higher than at the moderate temperature of 24 °C. However, male morph did not have interactive effects with temperature with respect to other life history traits (development time and longevity). Conclusions A male genotype that is associated with the expression of a SST interacted with temperature in determining male reproductive success. This interaction caused an elaborate SST to evolve in different directions (more or less prevalent) depending on the thermal environment. The implication of this finding is that seasonal temperature fluctuations have the potential to maintain male polymorphism within populations. Furthermore, spatial heterogeneity in thermal conditions may cause differences among populations in SST selection. This could potentially cause selection against male immigrants from populations in different environments and thus strengthen barriers to gene flow

No evidence for reproductive isolation through sexual conflict in the bulb mite Rhizoglyphus robini

Sexual conflict leading to sexual antagonistic coevolution has been hypothesized to drive reproductive isolation in allopatric populations and hence lead to speciation. However, the generality of this speciation mechanism is under debate. We used experimental evolution in the bulb mite Rhizoglyphus robini to investigate whether sexual conflict promotes reproductive isolation measured comprehensively to include all possible pre- and post-zygotic mechanisms. We established replicate populations in which we either enforced monogamy, and hence removed sexual conflict by making male and female evolutionary interests congruent, or allowed promiscuity. After 35 and 45 generations of experimental evolution, we found no evidence of reproductive isolation between the populations in any of the mating systems. Our results indicate that sexual conflict does not necessarily drive fast reproductive isolation and it may not be a ubiquitous mechanism leading to speciation

Modelo bioético para el análisis de la habitabilidad en la vivienda

La habitabilidad se refiere a estas configuraciones del espacio edificado, y se expresa en las diferentes escalas y entornos que el ser humano ha creado para su desarrollo como especie.La habitabilidad, en palabras de Macías, es “la capacidad de los espacios construidos para satisfacer las necesidades objetivas y subjetivas de los individuos, en estrecha relación con los ambientes socioculturales y naturales hacia la mejora de la calidad de vida”. (De Hoyos Martínez, et al., 2014)El ser humano ha modificado la configuración del espacio que lo rodea a lo largo de la historia, con el fin de hacer del mundo un lugar habitable, adaptándolo para proveerse de sitios para vivir, descansar, transitar, en fin, para realizar todas sus actividades cotidianas. Dichas modificaciones tienen lugar en las diversas escalas del espacio construido, entre los que se encuentran la vivienda, el barrio y la ciudad, y que, según Paola Coppola (2004), varían de acuerdo con las características socio-territoriales dentro de las que son creadas

Genome-wide meta-analysis of 241,258 adults accounting for smoking behaviour identifies novel loci for obesity traits

Few genome-wide association studies (GWAS) account for environmental exposures, like smoking, potentially impacting the overall trait variance when investigating the genetic contribution to obesity-related traits. Here, we use GWAS data from 51,080 current smokers and 190,178 nonsmokers (87% European descent) to identify loci influencing BMI and central adiposity, measured as waist circumference and waist-to-hip ratio both adjusted for BMI. We identify 23 novel genetic loci, and 9 loci with convincing evidence of gene-smoking interaction (GxSMK) on obesity-related traits. We show consistent direction of effect for all identified loci and significance for 18 novel and for 5 interaction loci in an independent study sample. These loci highlight novel biological functions, including response to oxidative stress, addictive behaviour, and regulatory functions emphasizing the importance of accounting for environment in genetic analyses. Our results suggest that tobacco smoking may alter the genetic susceptibility to overall adiposity and body fat distribution.Peer reviewe

Malignant tumors of the external and middle ear in patients at the age above 60 year-old

Wstęp. Nowotwory ucha to rzadka grupa schorzeń. Stanowią mniej niż 0,05% wszystkich guzów głowy i szyi. W niniejszej pracy przedstawiono wyniki postępowania u chorych po 60 roku życia, leczonych z powodu nowotworów złośliwych ucha zewnętrznego i środkowego. Materiał i metody. Dokonano retrospektywnej analizy danych dotyczących chorych operowanych w latach 1992-2001. W omawianym przedziale czasu leczono 56 pacjentów. Czterdzieści cztery osoby miały ponad 60 lat. Rozpatrywano częstość choroby w poszczególnych grupach wiekowych, zaawansowanie i typ histologiczny guzów. Oceniano sposoby zastosowanego leczenia oraz odległe wyniki terapii. Wyniki. Szczyt zapadalności na raka ucha występował w 8. dekadzie życia (29% operowanych). Najczęstszym nowotworem był rak podstawnokomórkowy (85% przypadków), zlokalizowany na małżowinie usznej w stadium zaawansowania T1. W uchu środkowym najczęściej opisywano raka płaskonabłonkowego w stadium T2. Ponadto w kilku przypadkach opisano gruczolakoraka i czerniaka. Leczenie obejmowało chirurgiczne wycięcie guza, które u niemal 20% chorych uzupełniono radio- i chemioterapią. Wnioski. Około 80% nowotworów złośliwych ucha zewnętrznego i środkowego stwierdza się u chorych po 60 roku życia. Występują z podobną częstością u obojga płci. W badanej grupie przeżycia 5-letnie wynosiły niemal 80%.Background. Tumors of the ear are rare. They account less than 0.05% of all head and neck neoplasms. We present results of treatment patients with malignant external and middle ear tumors at the age above 60 yearold. Material and methods. Retrospective analysis data of patients treated between 1992 and 2001 was performed. In that time 56 patients with malignant ear tumors were treated, 44 people were at the age above 60 year-old. We discuss frequency of diseases according to patient’s age, their local progression and histopathological type. We evaluate kinds of performed treatment and distant results of therapy. Results. These tumors occur especially in older people, with maximum in 8 decade (ca 30%). The most common lesion was basal cell carcinoma (ca 75% cases) located on auricle in T1 staging. While in the middle ear squamous cell carcinoma in T2 staging was observed the most often. In some cases adenocarcinoma and malignant melanoma were noticed. Treatment concerned surgical resection and in 20% cases radio and chemiotherapy was performed. Conclusions. About 80% of malignant tumors of external and middle ear were observed in patients at the age above 60 year-old. Tumors appeared in males and females with the same frequency. In our population 5 years survival was about 80%

full_dataset

The number of eggs (fecundity) and fertility (fertile collumn; fertile females are coded with 1 and infertile with 0) of females from scrambler (s) and fighter (f) selected lines (sel) at different temperatures (temp). Line identities are given in lineID collumn