Frequent misdirected courtship in a natural community of colorful Habronattus jumping spiders.

Male courtship display is common in many animals; in some cases, males engage in courtship indiscriminately, spending significant time and energy courting heterospecifics with whom they have no chance of mating or producing viable offspring. Due to high costs and few if any benefits, we might expect mechanisms to evolve to reduce such misdirected courtship (or 'reproductive interference'). In Habronattus jumping spiders, males frequently court heterospecifics with whom they do not mate or hybridize; females are larger and are voracious predators, posing a severe risk to males who court indiscriminately.

Molecular tracking of individual host use in the Shiny Cowbird - a generalist brood parasite.

Generalist parasites exploit multiple host species at the population level, but the individual parasite's strategy may be either itself a generalist or a specialist pattern of host species use. Here, we studied the relationship between host availability and host use in the individual parasitism patterns of the Shiny Cowbird Molothrus bonariensis, a generalist avian obligate brood parasite that parasitizes an extreme range of hosts. Using five microsatellite markers and an 1120-bp fragment of the mtDNA control region, we reconstructed full-sibling groups from 359 cowbird eggs and chicks found in nests of the two most frequent hosts in our study area, the Chalk-browed Mockingbird Mimus saturninus and the House Wren Troglodytes aedon.

Pollinator-prey conflicts in carnivorous plants: When flower and trap properties mean life or death.

Insect-pollinated carnivorous plants are expected to have higher fitness if they resolve pollinator-prey conflicts by sparing insects pollinating their flowers while trapping prey insects. We examined whether separation between flowers and traps of the carnivorous sundew species or pollinator preferences for colours of flowers enable these plants to spare pollinators. In addition, we collected odours from flowers and traps of each carnivorous species in order to identify volatile chemicals that are attractive or repellent to pollinators and prey insects.

The crystal structure of TrpD, a metabolic enzyme essential for lung colonization by Mycobacterium tuberculosis, in complex with its substrate phosphoribosylpyrophosphate.

Mycobacterium tuberculosis, the cause of tuberculosis, presents a major threat to human health worldwide. Biosynthetic enzymes that are essential for the survival of the bacterium, especially in activated macrophages, are important potential drug targets. Although the tryptophan biosynthesis pathway is thought to be non-essential for many pathogens, this appears not to be the case for M.