Two barnacles, Balanus and Chthamalus, can both survive on the lower rocks just above the low-tide line on the Scottish coast, but only Balanus actually does so, with Chthamalus adopting a higher zone. Which of the following best accounts for this niche separation?
a. competitive exclusion
b. predation of Chthamalus by Balanus
c. cooperative displacement
d. primary succession
e. mutualism
A. Competitive exclusion.
The competitive exclusion principle, also referred to as Gause's Law, states that two species that compete for the exact same resources in an ecosystem cannot stably coexist.
Two barnacles, Balanus and Chthamalus, can both survive on the lower rocks just above the low-tide...
) Barnacles (hard-shelled marine invertebrates) live on rocks in the intertidal zone. In an experiment involving two species, Semibalanus balanoides and Chthamalus stellatus, they were found to be able to coexist. The Semibalanus species was found to have rapid growth, and the ability to crush slower-growing Chthamalus species. However, the Chthamalus species was found to tolerate dry conditions. These species were therefore found to exist in two distinct bands, one higher and one lower, in the intertidal zone. All of...