A Finch Population with Heritable Variation in Beak Size Arrives

question 20

Multiple Choice

A finch population with heritable variation in beak size arrives on an island where only large seeds are available as a food source. Describe the process of natural selection that would follow.

• A) Finches with smaller beaks would grow larger beaks so that they could eat the large seeds. All birds will reproduce and the frequency of large beaks within the population will increase.
• B) Finches with larger beaks will more easily eat the large seeds and are thus more likely to survive and produce offspring with similarly large beaks. The frequency of large beaks within the population will increase.
• C) All of the finches with small and medium beaks will soon die; all of the finches with large beaks will survive. The frequency of large beaks within the population will increase.
• D) Finches with smaller beaks would grow larger beaks so that they could eat the large seeds. Only these birds that grew larger beaks will reproduce and the frequency of large beaks within the population will increase.
• E) Finches with larger beaks will more easily eat the large seeds and not need to reproduce. On an island where only large seeds are available for food, those birds with large beaks will more easily manipulate the food, outcompete those birds with smaller beaks, and have more time to reproduce. Birds with smaller beaks must work harder obtaining food and thus have less time to reproduce. The next generation of birds will be comprised mostly of birds with larger beaks.

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Definitions:

Control Circuit

Used in reference to both cranking systems and air brake systems. In a cranking system, it is the low-current switching circuit that connects the ignition switch with the magnetic switch. In an air brake system, it defines low-volume pilot air signals that are used to activate high-volume slave circuits.

Terminals

Terminals refer to the points at which electrical connections are made to a circuit, device, or a battery, facilitating the transfer of electrical power or signals.

Blade Fuses

Electrical components that protect circuits by melting and breaking the connection when current exceeds safe levels, characterized by their flat, plug-in design.