Is inbreeding avoidance driving female mate choice in Verreaux's sifaka lemurs?

Females of different species might exert female mate choice for different reasons, one of them the aim of avoiding inbreeding. In this study I examine the implication of inbreeding avoidance as a mechanism driving female mate choice in Verreaux’s sifaka lemurs (Propithecus verreauxi). In fact, in this species females are dominant and appear to be able to choose certain males to mate with, while observations indicate that rank, body size, canine size and proportions of fights won are not factors influencing female mate choice. So I hypothesized that females mate choice is driven by inbreeding avoidance in Verreaux’s sifaka lemurs. Tissue and fecal samples were collected in the Kirindy Mitea National Park in western Madagascar as a source of DNA. Parentage was assigned for a sample of the population and relatedness coefficients between dams and sires were estimated and compared to those of between random female and male pairs, dams and other candidate sires within the population and within the groups were the offspring were conceived. I found that there were no significant differences in none of the comparisons which means that Verreaux’s sifaka females do not mate more with males that are more distantly related to them. I concluded that inbreeding avoidance does not appear to be the main force driving female mate choice in Verreaux’s sifaka lemurs and I addressed explanations for these findings. With this study I contribute to our knowledge of female mate choice in lemurs.

Perfil motivacional de las mujeres participantes en la prueba atlética de los 3000 metros obstáculos

[ES] Los 3000 metros obstáculos es una especialidad del atletismo ubicada dentro de las pruebas de medio fondo, que comprende la carrera plana y el paso de los obstáculos, incluyendo un foso agua llamado ría. Es la especialidad de atletismo con menos participantes en carrera ya sea en género femenino como en masculino, pero ¿A qué se debe esta baja participación? Tanto la alta exigencia técnica en carrera como los pasos de los obstáculos son una de las razones, ya que, el paso de la ría requiere una refinada técnica y dificultad adquirida. Este estudio analizará a distintas atletas, con el fin de crear el perfil motivacional de las atletas que compiten en esta prueba, encontrar las razones por las que se decantan por otras especialidades del atletismo y no por esta, y con ello averiguar las razones de la baja participación en esta modalidad.

Mugilid Fish Are Sentinels of Exposure to Endocrine Disrupting Compounds in Coastal and Estuarine Environments

Effects on fish reproduction can result from a variety of toxicity mechanisms first operating at the molecular level. Notably, the presence in the environment of some compounds termed endocrine disrupting chemicals (EDCs) can cause adverse effects on reproduction by interfering with the endocrine system. In some cases, exposure to EDCs leads to the animal feminization and male fish may develop oocytes in testis (intersex condition). Mugilid fish are well suited sentinel organisms to study the effects of reproductive EDCs in the monitoring of estuarine/marine environments. Up-regulation of aromatases and vitellogenins in males and juveniles and the presence of intersex individuals have been described in a wide array of mullet species worldwide. There is a need to develop new molecular markers to identify early feminization responses and intersex condition in fish populations, studying mechanisms that regulate gonad differentiation under exposure to xenoestrogens. Interestingly, an electrophoresis of gonad RNA, shows a strong expression of 5S rRNA in oocytes, indicating the potential of 5S rRNA and its regulating proteins to become useful molecular makers of oocyte presence in testis. Therefore, the use of these oocyte markers to sex and identify intersex mullets could constitute powerful molecular biomarkers to assess xenoestrogenicity in field conditions.