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Interactions between hosts and pathogens are dynamic at both ecological and evolutionary levels. In the resultant 'eco‐evolutionary dynamics' ecological and evolutionary processes affect each other. For example, the house finch Haemorhous mexicanus and its recently emerged pathogen, the bacterium Mycoplasma gallisepticum, form a system in which evidence suggests that changes in bacterial virulence through time enhance levels of host immunity in ways that drive the evolution of virulence in an arms race.We use data from two associated citizen science projects in order to determine whether this arms race has had any detectable effect at the population level in the north‐eastern United States.We used data from two citizen science projects, based on observations of birds at bird feeders, which provide information on the long‐term changes in sizes of aggregations of house finches (host population density), and the probabilities that these house finches have observable disease (disease prevalence).The initial emergence of M. gallisepticum caused a rapid halving of house finch densities; this was then followed by house finch populations remaining stable or slowly declining. Disease prevalence also decreased sharply after the initial emergence and has remained low, although with fluctuations through time. Surprisingly, while initially higher local disease prevalence was found at sites with higher local densities of finches, this relationship has reversed over time.The ability of a vertebrate host species, with a generation time of at least 1 year, to maintain stable populations in the face of evolved higher virulence of a bacterium, with generation times measurable in minutes, suggests that genetic changes in the host are insufficient to explain the observed population‐level patterns. We suggest that acquired immunity plays an important role in the observed interaction between house finches and M. gallisepticum. [ABSTRACT FROM AUTHOR]

In the northeast United States, control of West Nile virus (WNV) vectors has been unfocused because of a lack of accurate knowledge about the roles different mosquitoes play in WNV transmission. We analyzed the risk posed by 10 species of mosquitoes for transmitting WNV to humans by using a novel risk-assessment measure that combines information on the abundance, infection prevalence, vector competence, and biting behavior of vectors. This analysis suggests that 2 species (Culex pipiens L. and Cx. restuans Theobald [Diptera: Cilicidae]) not previously considered important in transmitting WNV to humans may be responsible for up to 80% of human WNV infections in this region. This finding suggests that control efforts should be focused on these species which may reduce effects on nontarget wetland organisms. Our risk measure has broad applicability to other regions and diseases and can be adapted for use as a predictive tool of future human WNV infections. [ABSTRACT FROM AUTHOR]

The article presents the study on the strategies that will protect biodiversity of species in the U.S. It states that the observed distribution of endangered species reflects modification of underlying pattern of biodiversity by anthropogenic activities. It notes the need of a mixture of strategies to protect the species and their habitats. It mentions that conserving biodiversity requires greater focus.