In groups, start with a brainstorming session on what you know and don\'t know about mosquitoes in general. The class will compare lists to see how much collective information we can gather. Include, specifically, these questions in your brainstorming: Why were the researchers planning to use only female mosquitoes? Why do female mosquitoes bite for a blood \"meal\" in the first place? What do male and female mosquitoes live on as their main nutrient source (if only females take blood meals)? Continuing in your groups, work on the following: Based on the information above, write a plausible hypothesis that describes a possible mechanism to explain the differences between the forest and domestic forms in terms of their specific preferences for humans Based on your hypothesis, write one or more specific predictions that you could experimentally test. Draw a cartoon of a specific experiment you would want to design to test your predictions. During the lab meeting described in Part I of this case study. Carolyn brought up the concept of \"what makes a species one species.\" The most common way that scientists define species is called the \'biological species concept\" (BSC). Define the BSC What are the criteria used in the BSC in define a species? Solution Blood-feeding as a behavioural adaptation is exceedingly rare in insects. Of the 1-10 million insect species on earth, only ~10,000 feed on the blood of live animals. Among these, only about 100 species blood-feed preferentially on humans. When biting insects evolve to prefer humans, they can spread diseases such as malaria and dengue fever with devastating efficiency. The mosquito Aedes aegypti provides one of the best examples of specialization on humans. It originated as a wild, animal-biting species in the forested areas of sub-Saharan Africa, where the subspecies Ae. aegypti formosus is still often found living in forests and biting non-human animals today. The derived non-African subspecies Ae. aegypti aegypti, in contrast, has evolved to specialise in biting humans and thus has become the major worldwide vector of dengue and yellow fevers. The evolutionary adaptations that help subspecies aegypti exploit humans are most clearly seen where it has been reintroduced along the coast of East Africa and is known as the ‘domestic’ form. Researchers investigating the outbreak of an unknown illness in Tanganyika in 1952 discovered homes heavily populated by brown-pigmented ‘domestic’ mosquitoes. Subsequent work in the Rabai region of Kenya in the 1960s and 1970s showed that domestic mosquitoes readily entered homes, preferred to lay eggs in nutrient-poor river and rain water stored in containers indoors, were resistant to starvation as larvae, and had evolved a strong preference for biting humans. Black-pigmented populations of the native African subspecies formosus, known in Rabai as the ‘forest’ form, were found just hundreds of meters away avoiding homes, laying their eggs in tree holes and ro.