Does Wolbachia infection affect Trichogramma atopovirilia behaviour?

Unisexual Trichogramma forms have attracted much attention due to their potential advantages as biocontrol agents. Fitness studies have been performed and understanding the cost that Wolbachia may inflict on their hosts will help in deciding if Wolbachia infected (unisexual) forms are indeed better than sexual forms when used in biological control programmes. The influence of Wolbachia on the foraging behaviour (including walking activity and speed) of T. atopovirilia is reported in this paper. Temperature strongly affected T. atopovirilia female walking activity, but Wolbachia infected and uninfected females differed in none of the behavioural components that were measured such as walking activity and walking speed. Walking activity was highest at 25 ºC and differed significantly from that at 20 and 15 ºC. Trichogramma wasps were highly affected at 15 ºC. Behaviour analysis with females showed that female wasps spend most of the time on drilling + ovipositing on host eggs followed by host drumming and walking while drumming. The parasitism rate and number of offspring did not differ significantly between infected and cured Trichogramma females. Biological control implications of these findings are discussed

Serious delinquent behavior, sensation-seeking and electrodermal arousal

Low tonic skin conductance level (SCL) has been related, inconsistently, to both delinquency and sensation-seeking. This study tests the hypothesis that there is an interaction such that high sensation seeking delinquents, in particular, have low SCLs. Participants consisted of 335 boys from the Pittsburgh Youth Study classified as serious delinquents or controls based upon 10 years of prospectively collected self-report delinquency data. Participants' skin conductance was evaluated at age 16 along with several personality and neuropsychological measures. Both delinquency and sensation seeking were characterized by low SCL. However, there was no evidence to suggest that the presence of both of these factors together lead to especially low skin conductance levels. This finding is not explained by differences between the groups on measures of negative emotionality, IQ, socioeconomic status, or impulsivity

Losing the desire: selection can promote obligate asexuality

Whilst parthenogenesis has evolved multiple times from sexual invertebrate and vertebrate lineages, the drivers and consequences of the sex-asex transition remain mostly uncertain. A model by Stouthamer et al. recently published in BMC Evolutionary Biology shows a pathway by which obligate asexuality could be selected for following endosymbiont infection