Search results for " Males"

Origin and evolution of Artemia reproductive and genetic diversity

2017

El modo de reproducción de una especie determina su diversidad genética y, a su vez, su éxito ecológico y evolutivo (Normarck et al., 2003; Simon et al., 2003; De Meeûs et al, 2007). En una población sexual, la recombinación meiótica permite que nuevas combinaciones de genes se formen y destruyan constantemente. De hecho, las poblaciones sexuales son generalmente más diversas genéticamente en comparación con las poblaciones asexuales. Por el contrario, en un linaje estrictamente asexual, donde se supone que la mutación (con la mayoría de mutantes deletéreos) sea la única fuente de diversidad genética, se espera que la diversidad clonal de la población se reduzca en cada generación. Por esto…

Presentation of females and males in an English textbook series for Finnish upper-secondary schools

1997

Data from: Effects of inbreeding on a gregarious parasitoid wasp with complementary sex determination

2017

Inbreeding and inbreeding depression are processes in small populations of particular interest for a range of human activities such as animal breeding, species conservation or pest management. In particular, biological control programs should benefit from a thorough understanding of the causes and consequences of inbreeding because natural enemies experience repetitive bottlenecks during importation, laboratory rearing, and introduction. Predicting the effect of inbreeding in Hymenopteran parasitoid wasps, frequently used in biological control programs, is nonetheless a difficult endeavor. In haplodiploid parasitoids, the purge of deleterious alleles via haploid males should reduce genetic …

Data from: No inbreeding depression but increased sexual investment in highly inbred ant colonies

2012

Inbreeding can lead to the expression of deleterious recessive alleles and to a subsequent fitness reduction. In Hymenoptera, deleterious alleles are purged in haploid males moderating inbreeding costs. However, in these haplo-diploid species, inbreeding can result in the production of sterile diploid males. We investigated the effects of inbreeding on the individual and colony level in field colonies of the highly inbred ant Hypoponera opacior. In this species, outbreeding winged sexuals and nest-mating wingless sexuals mate during two separate reproductive periods. We show that regular sib-matings lead to high levels of homozygosity and the occasional production of diploid males, which sp…

Testosterone and cortisol responses to competitive fighting in human males: A pilot study

1987

Departamento de Psicologia Fisiologica (A.S., V.S., F.S.) and Laboratorio de MedicinaNuclear e Isotopos (L.L.), Hospital Clinico Universitario, Universitat de Valencia, Valencia,SpainSerum testosterone and cortisol levels were measured by radioimmunoassay in 14young male judo competitors, in samples taken 10 minutes before and 45 minutes aftertwo different pr(Redures. The first involved physical exercise and the second competi-tive fighting. Both procedures were of 5 minutes duration and sessions took plate atthe same time (between 10:00 \.M. and 12:00 P.M. liR-al lime) but on different days.Comparing the two situations over all subjects revealed that testosterone increasedafter exercise an…

Sexual dimorphism in the vertebral wedging of the human lumbar vertebrae and its importance as a comparative framework for understanding the wedging …

2020

Lumbar lordosis is a key element of the upright posture, being interpreted as a consequence of bipedal locomotion. There is consensus that the generic modern human pattern of metameric vertebral body wedging is sexually dimorphic in modern humans. However, recently published studies have compared this pattern with other hominins, such as Neanderthals. These tried to establish whether the (male) Neanderthal lumbar vertebrae express a pattern that falls within or outside the range of modern human males. In the present study, data collected by 3D landmarks of the lumbar vertebrae of modern humans from different geographic regions and Neanderthals (Ntotal = 505 individual vertebrae) are used to…

Long-term physical activity modifies automatic visual processing

2019

Electrophysiologically registered visual mismatch negativity (vMMN) is known to represent automatic visual processing in human visual cortex. Since physical activity (PA) is generally beneficial to cerebrovascular function, we wanted to find out if automatic visual processing is affected by PA. We investigated the connection between long-term leisure-time PA and precognitive visual processing in 32 healthy young males. Participants were divided into active (n = 16) and inactive (n = 16) group according to their leisure-time PA records from the past three years. vMMN was recorded with electroencephalogram using passive oddball paradigm with visual bars. Standard (90%) and deviant (10%) stimu…