Question

Which two hypotheses describing invasive species suggest that introducing a disease that attacks the invasive species from the native range of the invasive species would lead to a decrease (control) of an invasive species? Evolution of Increased Competitive Ability (EICA) and Darwin's Naturalization Hypothesis (DNH) Equilibrium Theory of Island Biogeography and Evolution of Increased Competitive Ability (EICA) Enemy Release Hypothesis (ERH) and Evolution of Increased Competitive Ability (EICA) Darwin's Naturalization Hypothesis (DNH) and Enemy Release Hypothesis (ERH) Question 38 2.5 pts Imagine a crayfish species originally from the east coast of Russia has invaded Alaska. (Crayfish are a species of freshwater crustaceans resembling small lobsters.) How would you test whether it has benefited from the Enemy Release Hypothesis (ERH)? Compare damage or loss by enemies (diseases, predators) on the invading crayfish species in the new range (Alaska) versus other crayfish species in the original range of the invading crayfish species (east coast of Russia) Compare damage or loss by enemies (diseases, predators) on the invading crayfish species in the original range (east coast of Russia) versus other crayfish species in the original range of the invading crayfish species (east coast of Russia) Compare damage or loss by enemies (diseases, predators) on the invading crayfish species versus damage or loss on native small crayfish species in the same community in the new range of the invading crayfish species (Alaska) Compare damage or loss by enemies (diseases, predators) on the invading crayfish species in the new range (Alaska) versus the original range of the invading crayfish species (east coast of Russia)

Answer 1

Answer 1. – Option D – DNH and ERH

According to Darwin's naturalization hypothesis invaders that are closely related to native taxa are less likely to be successful than those that are not.

Enemy release Hypothesis-

According to this hypothesis seed predation suppress plant population growth, these seed predator attack on native plants more than immigrating non-native species, and non-native plants are able to leverage this advantage into more rapid population growth.

Answer 2. – Option A

Enemy release Hypothesis-

The enemy release hypothesis is most often applied to invasive plants, but there is evidence for its usefulness in other systems also. This hypothesis assume that seed predation suppress plant population growth, these seed predator attack on native plants more than immigrating non-native species, and non-native plants are able to leverage this advantage into more rapid population growth. It assumes that in these new areas non-native species “escape” from their natural enemies. As a result, the need of defense against the enemy attack is restricted, or totally eliminated. Thats why to check the damage we have to test the condition of Cray fish in twodifferent systm on the basis of native and non-native habitate.