Question

An invasive plant gets into your garden. It spreads through and out-competes all of you plants, reducing the local diversity. Which principle applies most directly?

		character displacement
		sympatric and allopatric speciation
		random variation and stochasticity
		competitive exclusion principle

A male stickleback fish has a violent response pattern to the sight of other male sticklebacks. What sensory system is being stimulated?

		Proprioception
		Electromagnetic reception
		Baroreception
		Gustation

Answer 1

1. Correct answer is (D) competitive exclusion principle as:

(a) Character displacement is the term used to describe an evolutionary change that occurs when two similar species inhabit the same environment.

(b) In allopatric speciation, groups from an ancestral population evolve into separate species due to a period of geographical separation. In sympatric speciation, groups from the same ancestral population evolve into separate species without any geographical separation.

(c) Demographic stochasticity describes the random fluctuations in population size that occur because the birth and death of each individual is a discrete and probabilistic event.

(d) The principle of competitive exclusion was proposed by G.F. Gause which states that two species competing for the same resources cannot coexist. This law is also known as Gause’s law.One population will drive off the other one. If any of the members of the depleted population remains, that would be because they have adapted themselves according to the different niche.

2. The correct answer is (a) Proprioception

(a) Proprioception is the ability to know where and how your body is oriented in your surroundings.

(b)Electroreception simply means the ability to detect electrical currents.

(c)Baroreception (or archaically, pressoreceptors) is sensing through pressure.

(d) Taste perception or gustation is the sensory detection of food on the tongue.