Current Projects

Lab colonies of Culex molestus mosquitos

Mosquito larvae living in a discarded potato chip bag

Focus 1: Ecology and evolution of Northeast (USA) container mosquitos

Many species of mosquitoes live the larval portion of their lives in small bodies of water such as tree holes, rock pools, and with increasing frequency water-holding manmade objects. These objects include old tires, buckets and discarded trash. Many container mosquitoes are also important disease vectors. The Aardema lab works on numerous aspects of the ecology and evolution of such mosquitoes. Specific projects include phylogenetic analysis of the Culex pipiens species complex, how predation mediates competition among container mosquitos, and epigenetic changes in relation to mosquito aging. A particular focus of the lab is the urban adapted mosquito Culex molestus. This is a unique strain of mosquito that in temperate climates is found exclusively in urban environments, often inhabiting sewer and subway systems. Unlike the closely related species, Cx. pipiens, it appears to feed predominately on mammalian hosts, including humans. It also has other unique ecological characteristics such as an ability to lay eggs without first taking a blood meal (autogeny) and an absence of winter diapause. These traits make Cx. molestus particularly amenable to lab-base research projects.

http://www.wnyc.org/story/seven-years-uws-mosquito-infestation-remains-mystery/

Alaskan mosquito

Focus 2: Convergent evolution in blood-feeding arthropods, with genome sequencing of fleas and outgroups

Blood represents a challenging and potentially toxic food source for most animal species. Yet numerous arthropods such as ticks, mosquitos, bedbugs and fleas have evolved the ability to utilize and thrive on vertebrate blood. Using genome data from a large number of species, the Aardema lab is investigating three areas of potential evolutionary convergence among blood-feeding arthropods: tyrosine detoxification, heme detoxification and water balance. Additionally, for this project we have sequenced the genomes of two flea species: Oropsylla hirsuta and O. tuberculata. These species are responsible for transmitting plague within prairie dog communities, and contribute to high mortality in the endangered black-footed ferret. In addition to our work on convergent evolution, we are also using these genomes to investigate the emergence of insecticide resistance in these fleas. 

Juvenile white-tailed deer in New Jersey

Focus 3: Characterization of enzootic cycles in the tick-vectored bacterium, Anaplasma phagocytophilum

A. phagocytophilum is a tick-transmitted, obligately intracellular pathogen of humans, pets and livestock. Strains of A. phagocytophilum display varying degrees of host specialization in Europe, but much less is known about host-affiliations and transmission cycles in North America. With mammalian and tick surveys, combined with whole-genome sequencing, the Aardema lab is working to better characterize the distinct cycles of A. phagocytophilum transmission in the Eastern United States. We are also interested in host adaptation and divergent selection in this bacteria. These inquires will ultimately lead to improved prevention of human, pet and livestock infections.