In the case of two competing barnacle species, the larger species Semibalanus is able to eliminate individuals of the smaller species Chthamalus through interference competition over its entire fundamental niche by overgrowing or dislodging them as they grow larger. Which of the following could be an explanation (reasonable hypothesis) that is sufficient to fully explain why Chthamalus evades competitive exclusion within the high-tide zone? Select one: a. The fundamental niche of Semibalanus extends over the entire tidal zone (both high and low-tide). b. Semibalanus is outcompeted by Chthamalus in the high-tide zone. c. The high-tide zone is outside the range of tolerance for Semibalanus. d. Chthamalus is competitively excluded in the low-tide zone. e. The fundamental niche of Chthamalus extends over the entire tidal zone (both high and low-tide).

Semibalanus can out-compete Chthamalus by crowding or smothering, but Chthamalus can occupy higher tide levels than Semibalanus because it is more resistant to desiccation.

The fundamental niche of Chthamalus includes both the upper and middle intertidal zones. - The realized niche of a species is a subset of the fundamental niche, limited by biotic interactions such as competition. The realized niche of Chthamalus is the upper intertidal zone only.