Little is known about how Drosophila adults behave in the wild, including mating, allocation of food and space, and escape from predators. This lack of information has negative implications for our ability to understand the capabilities of the nervous system to integrate sensory cues necessary for the adaptation of organisms in natural conditions. We characterized a set of behavioral routines of D. melanogaster and D. simulans adults in three ecologically different orchards: grape, apple and prickly pear. We also investigated how the flies identify conspecifics and aliens in the wild to better understand relationships between group formation and adaptation of Drosophila to breeding sites. We characterized the locations by recording in each orchard humidity, temperature, illumination conditions, pH of fruits, the presence/absence of other Drosophila species and the predator ant Linepithema humile. Our findings suggest that the home range of these species of Drosophila includes decaying fruits and, principally, a variety of microhabitats that surround the fruits. The ecological heterogeneity of the orchards and odors emitted by adult D. melanogaster and D. simulans influence perch preferences, cluster formation, court and mating, egg-laying site selection, and use of space. This is one of the first large examinations of the association between changing, complex environments and a set of adult behaviors of Drosophila. Therefore, our results have implications for understanding the genetic differentiation and evolution of populations of species in the genus Drosophila.

The existence nematodes of veterinary importance such as Haemonchus contortus resistant to anthelmintic drugs, including the macrocyclic lactones, has become a major concern in animal health. Macrocyclic lactone resistance in H. contortus seems to be multigenic including the active efflux of these drugs by P-glycoproteins, members of the ABC transporter family, present in this parasite. The goals of the present work were to determine the activity of H. contortus P-glycoprotein 9.1 (Hco-PGP-9.1) and its interaction with the avermectins, ivermectin, abamectin, and also the milbemycin, moxidectin. Additionally, the localisation of Hco-PGP-9.1 was sought in adult worms. Hco-Pgp-9.1 was cloned and expressed in mammalian cells and its expression profile was determined at the transcriptional and protein level by qRT-PCR and Western-blot, respectively. The nematode transport activity was assessed using the tracer dye Rhodamine 123. A ligand competition assay between different macrocyclic lactones and Rhodamine 123 was used to establish whether or not there was interaction between Hco-PGP-9.1 and the avermectins (abamectin and ivermectin) or moxidectin. In addition, immunostaining was carried out to localise Hco-PGP-9.1 expression in the transgenic cells and in adult female parasites. Hco-PGP-9.1 was expressed in the cell membrane of the transfected host cells and was able to extrude Rhodamine 123. Ivermectin and abamectin, but not moxidectin, had a pronounced inhibitory effect on the ability of Hco-PGP-9.1 to transport Rhodamine 123. Antibodies raised against Hco-PGP-9.1 epitopes localised to the uterus of adult female H. contortus. These results suggest a strong interaction of the avermectins with Hco-PGP-9.1. However, possibly due to its physico-chemical properties, moxidectin had markedly less effect on Hco-PGP-9.1. Because of the greater interaction of the avermectins than moxidectin with this transporter, it is more likely to contribute to avermectin resistance than to moxidectin resistance in H. contortus. Possible over expression of Hco-PGP-9.1 in the female reproductive system in resistant worms could reduce paralysis of the uterus by macrocyclic lactones, allowing continued egg release in drug challenged resistant worms.