Question

besides giving us a multitude of dog breeds, genetic variation is important because it allows populations to adapt to their environment. due to a variety of possible traits, populations can change over time as individuals with traits better suited to their environment more frequently survive and pass on their dna.
read about three different populations. which passage describes how genetic variation allowed a population to adapt to a changed environment?
a population of bacteria grew rapidly in a petri dish in a warm environment. every 20 minutes, each individual bacterium divided to produce a genetically identical clone. so the population doubled in size every 20 minutes! the petri dish was then moved to a much hotter environment. the bacteria could not withstand the hotter temperatures, and the whole population died.
in a population of birds - of - paradise, a male bird made loud calls to attract a female. he then showed off his iridescent feathers during an elaborate courtship dance to convince the female to mate with him. the dance took a lot of time and energy. the birds mated, and the female eventually laid a clutch of two eggs.
in a population of lizards, more lizards had light - colored skin than dark - colored skin. over time, the environment changed to have more dark - colored soil than pale sandy soil. after the environment changed, lizards with dark - colored skin were harder for predators to see, so they were more likely to survive and reproduce. eventually, a greater percentage of the lizard population had dark - colored skin than light - colored skin.

Explanation:

This passage shows genetic variation (light and dark skin) in the original lizard population. When the environment changed (darker soil), the dark-skinned lizards (a genetically different trait) had a survival advantage, survived to reproduce more, and the population adapted to the new environment over time. The bacteria population had no genetic variation and died, while the bird passage describes mating behavior, not adaptation to a changed environment via genetic variation.

Answer:

The passage about the lizard population: "In a population of lizards, more lizards had light-colored skin than dark-colored skin. Over time, the environment changed to have more dark-colored soil than pale sandy soil. After the environment changed, lizards with dark-colored skin were harder for predators to see, so they were more likely to survive and reproduce. Eventually, a greater percentage of the lizard population had dark-colored skin than light-colored skin."