Final answer:
Sexual pleasure derived from animals usually begins in males during adolescence as a transitory phenomenon.
Step-by-step explanation:
The study mentioned in your question by Earls and Lalumière (2009) discusses sexual pleasure derived from animals. According to their research, both males and females can experience specific arousal, but the sexual response differs in intensity and duration. The study suggests that this behavior usually begins in males during adolescence as a transitory phenomenon.