Question

a wildlife program has monitored a population of desert lizards for over 80 years. the lizard population has been highly successful during this time. biologists hypothesize that natural selection has been acting on the population, helping it thrive in its environment. select the three observations that best support this hypothesis.

• the lizards have been able to survive extreme temperature changes in their habitat.
• the lizards have been unable to survive shifts in their habitat conditions.
• most lizards appear nearly identical due to a lack of genetic variation.
• lizards show differences in traits such as skin color and behavior due to genetic diversity.
• the average number of eggs hatched has been less than the average number of adult deaths each year.
• the average number of eggs hatched has been greater than the average number of adult deaths each year.

Explanation:

To support the hypothesis of natural selection acting on the lizard population:

1. "The lizards have been able to survive extreme temperature changes in their habitat" shows adaptation (a result of natural selection) to the environment.
2. "Lizards show differences in traits such as skin color and behavior due to genetic diversity" provides genetic variation, a prerequisite for natural selection (variation in traits for selection to act on).
3. "The average number of eggs hatched has been greater than the average number of adult deaths each year" indicates population growth, consistent with a successful population thriving due to natural selection (more offspring survive than adults die, allowing population to persist/grow).

Options like "unable to survive shifts" (opposes success), "lack of genetic variation" (no variation for selection), and "eggs hatched < adult deaths" (population decline) do not support the hypothesis.

Answer:

1. The lizards have been able to survive extreme temperature changes in their habitat.
2. Lizards show differences in traits such as skin color and behavior due to genetic diversity.
3. The average number of eggs hatched has been greater than the average number of adult deaths each year.