Researchers have developed a new and quick way to determine whether southern cattle ticks (Rhipicephalus (Boophilus) microplus), also known as cattle fever ticks, are resistant to the commonly used pesticide permethrin. The test scans the DNA for mutations that confer resistance. Here, Guilherme Klafke, Ph.D., of Brazil’s Instituto de Pesquisas Veterinárias Desidério Finamor analyzes DNA in a sample to determine if the mutations are present. Klafke was one of the co-authors of a new research paper in the Annals of the Entomological Society of America that describes the new assay. (Photo by Jason Tidwell)