Further explanation of sexual selection definitions.
Members of the same sex (of the same species) compete, fight or engage in combat with one another over the opportunity to mate with a female.
As Darwin explains it "not on a struggle for existence, but on a struggle between the males for possession of the females"Intrasexual selection describes a situation in which reproductive success hinges on the actions of a single sex (Freeman & Herron, 2007).
Simply put, females choice. When the females chooses the best mate based on display or ornaments. Intersexual selection describes situations in which reproductive success is dependent on interplay between both sexes (Freemon & Herron, 2007).
Freeman, S. Herron, J. (2007). Evolutionary Analysis (4th ed.). San Francisco, CA: Pearson Benjamin Cummings.