Peter Fedor

Physical attractiveness influences reproductive success of modern men

Theory suggests that reproductive success is positively associated with an individual’s genetic quality. However, the association between physical attractiveness and reproductive success (i.e., number of offspring) in modern humans remains less clear. Here we examined associations between men’s reproductive success and physical attractiveness from retrospective data obtained from married, divorced, and single samples of Slovakian men. As predicted, facially more attractive and taller men were more likely to engage in marriage. In turn, married men had higher reproductive success than single men. Even when men’s marital status was considered, facially more attractive men had higher reproductive success than their less attractive counterparts. This supports the importance of physical attractiveness in sexual selection in modern humans.

Health Is Associated With Antiparasite Behavior and Fear of Disease-Relevant Animals in Humans

Evolutionary arms races between humans and parasites resulted in a set of behavioral adaptations that serve as parasite-avoidance mechanisms. We investigated associations among reported health of the respondent, antiparasite behavior, and sensitivity to disgust and fear of disease-relevant and irrelevant animals. Ninety-seven participants (15–19 years old) rated their fear and disgust at 25 colorful pictures of disease-relevant and disease-irrelevant invertebrates. Consistent with previous work, we found that participants reported greater fear and disgust of disease-relevant invertebrates relative to disease-irrelevant invertebrates. Better perceived health correlated with lower fear of disease-relevant invertebrates. Sensitivity to disgust correlated with reported antiparasite behaviors. Contrary to expectations, we found a positive correlation between antiparasite behavior and reported health, which suggests that antiparasite behavior influences perceived health (but not vice versa), and we found that males perform more antiparasite behaviors than females. These results support the idea that disgust and fear of disease-relevant objects are adaptive emotions that prevent contact with contagious objects, especially in individuals with low perceived health.

Thrips (Thysanoptera) identification using artificial neural networks.

We studied the use of a supervised artificial neural network (ANN) model for semi-automated identification of 18 common European species of Thysanoptera from four genera: Aeolothrips Haliday (Aeolothripidae), Chirothrips Haliday, Dendrothrips Uzel, and Limothrips Haliday (all Thripidae). As input data, we entered 17 continuous morphometric and two qualitative two-state characters measured or determined on different parts of the thrips body (head, pronotum, forewing and ovipositor) and the sex. Our experimental data set included 498 thrips specimens. A relatively simple ANN architecture (multilayer perceptrons with a single hidden layer) enabled a 97% correct simultaneous identification of both males and females of all the 18 species in an independent test. This high reliability of classification is promising for a wider application of ANN in the practice of Thysanoptera identification.

Paternity cues and mating opportunities: what makes fathers good?

Human males provide facultative paternal investment to their offspring; that is, the male care is not necessary for the survival of his offspring. It is expected that the degree of male investment (1) increases with growing paternity certainty, (2) increases when investment increases the survival and later reproductive prospect of offspring and (3) declines when there are opportunities to mate with multiple females. Using a large sample of adult offspring and their fathers (n = 245), we first investigated the role of two factors possibly involved in the assessment of paternity and subsequently regulating the level of paternal investment: (a) father–child facial resemblance and (b) assortative mating for eye colour. Second, because mating opportunities are inversely related to paternal investment, we also investigated how male facial attractiveness (a cue of mate opportunities) correlates with paternal investment. In line with paternal investment theory, male investment positively correlated with offspring facial resemblance. However, paternal investment were neither higher among blue-eyed couples, nor there were preferences of blue-eyed men to marry with blue-eyed women. Moreover, father facial attractiveness was unrelated to paternal investment. These results indicate that resemblance between offspring and their fathers still plays an important role in paternal investment decision later in offspring’s life.

Artificial intelligence in pest insect monitoring

Abstract Global problems of hunger and malnutrition induced us to introduce a new tool for semi‐automated pest insect identification and monitoring: an artificial neural network system. Multilayer perceptrons, an artificial intelligence method, seem to be efficient for this purpose. We evaluated 101 European economically important thrips (Thysanoptera) species: extrapolation of the verification test data indicated 95% reliability at least for some taxa analysed. Mainly quantitative morphometric characters, such as head, clavus, wing, ovipositor length and width, formed the input variable computation set in a Trajan neural network simulator. The technique may be combined with digital image analysis.

Parasites enhance self-grooming behaviour and information retention in humans.

Self-grooming is a common behavioural strategy used by various animals to reduce parasite loads. We experimentally tested the adaptive significance of self-grooming model in a sample of Slovak participants. Propensity to self-grooming was activated by visual presence of parasites with verbal information about health risks caused by parasites suggesting that the programmed grooming model works in humans. People who think of themselves as more vulnerable to disease transmission reported higher frequency of self-grooming suggesting that there is a link between the immune system and parasite avoidance behaviour. Considering that the emotion of disgust plays a role in activation of parasite avoidance behaviour, we suggested that knowledge of disgusting stimuli (parasites) would be better retained than knowledge of non-disgusting (hormones), and, thus, non-life-threatening stimuli. As expected, knowledge on parasites tested immediately after the experiment was significantly better than knowledge on hormones suggesting that survival-relevant information is better retained than survival-irrelevant data. However, scores on memory tests did not seem to be influenced by the individuals immune system. Overall, this study showed that self-grooming in humans is functional when disease threat is salient. Human memory systems are tuned to information relevant to survival providing further evidence that human cognition is shaped by natural selection.

Associations between body morphology, mating success and mate preferences among Slovak males and females.

Human body morphology is thought to be correlated with sexual behaviour and sociosexuality (defined as an increased willingness to engage in sex without commitment) influences the perception of certain cues of physical attractiveness. Based on a sample of Slovak university students, we investigated relationships between 1) male and female mating success and reported body morphology (body mass index, BMI and waist-to-hip ratio, WHR) and 2) mate preference characteristics and mating success. Both males and females reported a similar number of long-term sexual partners and frequency of engaging in extra-pair copulation (EPC). The mating success of both sexes was positively mediated by self-perceived attractiveness. However, female BMI was inversely associated with mating success whereas increasing BMI was positively associated with male mating success (the total number of lifetime sexual partners) as well as with the likelihood of engaging in EPC. Unrestricted sociosexuality positively correlated with direct and indirect benefits from mating and negatively with the religious/political background of a potential mate and with the desire for a home/ children. These results confirm the hypothesis that human body morphology is associated with sexual behaviour and that cues of direct/indirect benefits in a potential mate positively correlate with sociosexuality.

“Testing the limits” — an interesting record of the exotic banded greenhouse thrips Hercinothrips femoralis (Thysanoptera: Thripidae: Panchaetothripinae) at high Carpathian mountain altitudes

This study deals with an interesting record of exotic pest thrips Hercinothrips femoralis (Reuter, 1891) small population in the Carpathian mountain area (Vysoké Tatry Mts, N Slovakia) during the extensive research on high altitude forest succession. Hercinothrips femoralis is a well-known African pest species that has been introduced into the temperate regions of Europe, surviving only in glasshouses. The record in the coldest altitudes ever published (more than 1,000 m a.s.l.) indicates a role of passive migration and an effort of insects to taste ecological and environmental limits in their distribution.

Application of PCA in Taxonomy Research – Thrips (Insecta, Thysanoptera) as a Model Group

In analysis of principal components, eigenvalues represent the relative participation of each principal component in presenting the general variability of sampled material. The numerical value of a given eigenvalue is a direct indicator of the weight of a particular component in the general characteristics of the variability of a set of data. In practice, the distribution of the elements of the analyzed set in the space of the first three or four components allows one to present almost the complete diversity of the set.

The first record of predaceous Scolothrips longicornis Priesner 1926 (Thysanoptera: Thripidae) in Slovakia

This preliminary communication presents the first record of predaceous thrips Scolothrips longicornis Priesner, 1926 (Thysanoptera: Thripidae) in Slovakia. As a well known predator of numerous spider mites, e.g. Tetranychus urticae or Eutetranychus orientalis it has been considered as a suitable biological control agent recently. Tetranychids mites are harmful agriculture pests, causing damage on a variety of greenhouse and field crops (e.g. cucumber, peppers, tomatoes, potatoes, beans, corn, strawberries) and are difficult to control chemically. Scolothrips longicornis was recorded in soil and a tree photoeclector samples from Babsky les wood, a natural oak-hornbeamforest (Fageto – Quercetum), situated in the district of Nitra (SW Slovakia).