Ecology and phenology of the bat tick () (Acari: Argasidae).

Although 12 soft tick species (Argasidae) are native to Australia, the ecology of most is poorly known. parasitizes several insectivorous bat species and has been recorded on humans. Therefore, understanding its ecology is crucial for wildlife health management and public health preparedness.

Experimental immune challenges reduce the quality of male antennae and female pheromone output.

Sexual signalling is a key feature of reproductive investment, yet the effects of immune system activation on investment into chemical signalling, and especially signal receiver traits such as antennae, are poorly understood. We explore how upregulation of juvenile immunity affects male antennal functional morphology and female pheromone attractiveness in the gumleaf skeletonizer moth, Uraba lugens. We injected final-instar larvae with a high or low dose of an immune elicitor or a control solution and measured male antennal morphological traits, gonad investment and female pheromone attractiveness.

Sexual conflict and correlated evolution between male persistence and female resistance traits in the seed beetle .

Traumatic mating (or copulatory wounding) is an extreme form of sexual conflict whereby male genitalia physically harm females during mating. In such species females are expected to evolve counter-adaptations to reduce male-induced harm. Importantly, female counter-adaptations may include both genital and non-genital traits.

Male-biased sex ratio does not promote increased sperm competitiveness in the seed beetle, Callosobruchus maculatus.

Sperm competition risk and intensity can select for adaptations that increase male fertilisation success. Evolutionary responses are examined typically by generating increased strength of sexual selection via direct manipulation of female mating rates (by enforcing monandry or polyandry) or by alteration of adult sex ratios. Despite being a model species for sexual selection research, the effect of sexual selection intensity via adult sex-ratio manipulation on male investment strategies has not been investigated in the seed beetle, Callosobruchus maculatus.

Why do female Callosobruchus maculatus kick their mates?

Sexual conflict is now recognised as an important driver of sexual trait evolution. However, due to their variable outcomes and effects on other fitness components, the detection of sexual conflicts on individual traits can be complicated. This difficulty is exemplified in the beetle Callosobruchus maculatus, where longer matings increase the size of nutritious ejaculates but simultaneously reduce female future receptivity.

Rapid loss of behavioral plasticity and immunocompetence under intense sexual selection.

Phenotypic plasticity allows animals to maximize fitness by conditionally expressing the phenotype best adapted to their environment. Although evidence for such adjustment in reproductive tactics is common, little is known about how phenotypic plasticity evolves in response to sexual selection. We examined the effect of sexual selection intensity on phenotypic plasticity in mating behavior using the beetle Callosobruchus maculatus.

Quantitative genetic insights into the coevolutionary dynamics of male and female genitalia.

The spectacular variability that typically characterizes male genital traits has largely been attributed to the role of sexual selection. Among the evolutionary mechanisms proposed to account for this diversity, two processes in particular have generated considerable interest. On the one hand, females may exploit postcopulatory mechanisms of selection to favour males with preferred genital traits (cryptic female choice; CFC), while on the other hand females may evolve structures or behaviours that mitigate the direct costs imposed by male genitalia (sexual conflict; SC).

Age-dependent trade-offs between immunity and male, but not female, reproduction.

Immune function is costly and must be traded off against other life-history traits, such as gamete production. Studies of immune trade-offs typically focus on adult individuals, yet the juvenile stage can be a highly protracted period when reproductive resources are acquired and immune challenges are ubiquitous. Trade-offs during development are likely to be important, yet no studies have considered changes in adult responses to immune challenges imposed at different stages of juvenile development.

Estimating expenditure on male and female offspring in a sexually size-dimorphic bird: a comparison of different methods.

The parents of sexually size-dimorphic offspring are often assumed to invest more resources producing individuals of the larger sex. A range of different methods have been employed to estimate relative expenditure on the sexes, including quantifying sex-specific offspring growth, food intake, energy expenditure and energy intake, in addition to measures of parental food provisioning and energy expenditure. These methods all have the potential to provide useful estimates of relative investment, but each has particular problems of interpretation, and few studies have compared the estimates derived concurrently from more than two of these measures.

Nutritional bias as a new mode of adjusting sex allocation.

Sex biases in the allocation of resources to offspring occur in a broad range of taxa. Parents have been shown to achieve such biases either by producing numerically more of one sex or by providing the individuals of one sex with a greater quantity of resources. In addition, skews in allocation could occur if the offspring of one sex receive resources of higher quality (greater nutritional or energetic value by weight or volume), although this mode of adjustment has, to our knowledge, never been demonstrated.