The ability of malaria parasites to respond positively to the presence of feeding mosquito vectors would clearly be advantageous to transmission. In this study, Anopheles stephensi mosquitoes probed mice infected with the rodent malaria parasite, Plasmodium chabaudi. Growth of asexual stages was accelerated and gametocytes appeared 1-2 days earlier than in controls. This first study, to our knowledge, of the effects of mosquitoes on 'in-host' growth and development of Plasmodium has profound implications for malaria epidemiology, suggesting that individuals exposed to high mosquito numbers can contribute disproportionately high numbers of parasites to the transmission pool.

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Increasing reliance on deep-water renewable energy has increased concerns about the effects of the electromagnetic fields (EMFs) generated by submarine power cables on aquatic organisms. Off southern California, we conducted surveys of marine organisms living around energized and unenergized submarine power cables and nearby sea floor during 2012-2014 at depths between 76 and 213 m. In general, EMFs declined to background levels about one meter from the cable. We found no statistical difference in species composition between the fish assemblages along the energized and unenergized cables. The natural habitat community statistically differed from both energized and unenergized cable communities. Within species (or species groups), we found no differences in densities between energized and unenergized cables. Total fish densities were significantly higher around the cables than over the natural habitat. We found that invertebrate communities were structured by habitat type and depth and, similar to the fishes, there was no statistical difference between the energized and unenergized cables. Individually, the densities of four invertebrate species or species groups (Metridium farcimen, Luidia spp., unidentified black Crinoidea, and Urticina spp.) differed between energized and unenergized cables, but this difference was not significant across all depth strata. The invertebrate community inhabiting the natural habitat strongly differed from the energized and unenergized cable community exhibiting the fewest species and individuals.

Using video transects of oil and gas platform crossbeams off central and southern California, we characterized the structure-forming invertebrates (with a height of at least 20 cm) found around 23 oil and gas platforms at depths between 20 and 363 m. We observed 20,357 individual invertebrates, comprising 19,800 Cnidaria and 557 Porifera of at least 15 species or species groups. Metridium farcimen (Brandt, 1835) was by far the most commonly observed cnidarian, forming 97.6% of all invertebrates catalogued. The alcyonacean, Leptogorgia chilensis (Verrill, 1868), and the scleractinian, Lophelia pertusa (Linnaeus, 1758), were the most commonly observed corals. White vase sponges (most or all in the family Aphrocallistidae) were the most abundant of the sponges (comprising 38.4% observed). We also documented a variety of unidentified foliose, barrel, and other various-shaped sponges. The height of these invertebrates ranged from 20 to 80 cm. Taxa displayed a variety of depth patterns. Some, such as M. farcimen, unidentified white vase sponges, and L. pertusa, were found throughout most or all of the survey depth range, while others (notably the gorgonians L. chilensis, Placogorgia spp., and Acanthogorgia spp.) were found over a relatively narrow range. Invertebrate assemblages tended to be similar among many platforms reflecting species similarities over a broad range of platform depths. Based on these relationships, it is apparent that the assemblages of structure-forming invertebrates varied by depth rather than geography.

Between September and November in 1995 and 1998–2011, we conducted surveys of demersal fishes and their associated benthic habitats using direct observations from human-occupied vehicles over the Footprint, an isolated submerged ridge located seawards of the Santa Cruz Island-Anacapa Island Passage, Southern California, extending over bottom depths of about 94–500 m. The observed fish fauna, consisting of 127,351 individuals of at least 79 species, was dominated by rockfishes (genus Sebastes; 94.5% of individuals, 47% of species). The Footprint is home to a complex of benthic habitats that are occupied by a number of fish assemblages. These were defined by bottom depth, habitat type, and the environmental tolerances and preferences of each species. While the habitat-limited benthic species that occupy the shallower parts of the Footprint are isolated from the Santa Cruz Island and Anacapa Island shelves, the fishes living on the Footprint are not reproductively isolated. Rather, through a web of connections, the fishes of the Footprint are likely well integrated into the Southern California Bight. This connectivity, flowing towards and away from the Footprint, means that events hundreds or thousands of kilometers away may have profound effects on the fish assemblages on this feature. For example, economically important species were relatively uncommon, possibly the result of past overfishing locally and a lack of immigration from other regions.