Define directional selection by choosing the most accurate description.

Which of the following is true for Diversifying selection?

Write the correct type of selection (Diversifying, Directional, or Stabilizing). Starlings produce an average of five eggs in each clutch; clutches with more than five cannot be fed adequately and clutches with fewer than five are more vulnerable to predation, so five becomes the most common clutch size.

Write the correct type of selection (Diversifying Directional, or Stabilizing). Seed cracker birds have either large beaks or small beaks; medium beaks do not allow adequate cracking of seeds, so mediums are rare.

Write the correct type of selection (Diversifying, Directional, or Stabilizing). In an oak population, acorns with a 2 cm circumference are most common and survive; very small (1 cm) and very large (3 cm) acorns are rare and do not persist.

Write the correct type of selection (Diversifying, Directional, or Stabilizing). Lizards with small heads cannot eat the largest cockroaches and prey on smaller sizes instead; over time, lizards with larger heads survive better.

Write the correct type of selection (Diversifying, Directional, or Stabilizing). Female birds laying close to the optimum number of eggs have the most surviving offspring; laying fewer or more reduces fitness.

Write the correct type of selection (Diversifying, Directional, or Stabilizing). During a drought, only large, thick seeds are available; birds with large, thick beaks survive while small-beaked birds do not.

Write the correct type of selection (Diversifying, Directional, or Stabilizing). In a rocky environment with white and black rocks, black rabbits (BB) and white rabbits (bb) survive because they are able to camouflage in the environment, while intermediate gray rabbits (Bb) do not survive well.

Write the correct type of selection (Diversifying, Directional, or Stabilizing). Small lizards die because they cannot defend territories, and large lizards are eaten by owls; medium-sized lizards survive.

Write the correct type of selection (Diversifying, Directional, or Stabilizing). Very large human babies lead to labor complications and very small babies tend to be underdeveloped; medium-sized babies are most likely to survive to adulthood.

Label the type of selection shown by the graph. The post-selection distribution splits into two peaks at both extremes, leading to creation of two new species, while the intermediate values are reduced.

Read the scenario and identify the type of natural selection it illustrates: Seed cracker birds have either large beaks or small beaks; they do not have medium sized beaks because medium sized beaks do not allow for adequate cracking of seeds.

Read the scenario and identify the type of natural selection it illustrates: A scientist measures the circumference of acorns in a population of oak trees and discovers that the most common circumference is 2 cm. There are very few acorns with circumferences of 3 cm or 1 cm because only the 2 cm circumference acorns survive.

Read the scenario and identify the type of natural selection it illustrates: A population of Madagascar hissing cockroaches lives in a woodpile and is eaten by lizards. Because the lizards have small heads, they are unable to eat the very largest adult cockroaches and instead prey upon small and medium sized adults. Over time, larger-headed lizards have a survival advantage.

Label the type of selection represented by the graph described: The original population is a single peak, while the new distribution splits into two peaks on opposite extremes with low frequency in the middle.

Wild boars prefer to eat cacti with fewer spines and therefore cacti with fewer spines are eaten in greater quantity. Cacti with a more spines are more likely to survive, reproduce, and pass down their genes to the next generation. Which type of selection is occurring?

Over the years, white mice became extinct and darker mice survived. This is

Which of the following is true for natural selection?

What is the main purpose of adaptations in living organisms?

Which adaptation would most likely help a desert plant conserve water?