Suppose twin teenagers are competing for their mother’s atte…

Suppose twin teenagers are competing for their mother’s attention. The mother is trying to pay attention to one of her daughters, though both girls are talking (one about her boyfriend, one about a school project). According to the operating characteristics of Treisman’s attenuator, the attenuator is most likely analyzing the incoming message in terms of what?

In sociable weavers of the African savanna, optimal body mas…

In sociable weavers of the African savanna, optimal body mass is a trade-off between risk of starvation and predation. Birds that are fatter have low starvation risk but high predation risk. Birds that are thinner have low predation risk but high starvation risk. Therefore, the birds of medium weight are better adapted to their environment (graphed below). This is an example of what type of selection?