Darwin's Theory

Which would least likely be a cause of natural selection?

evolution

Consider this image of a gazelle. Which of the gazelle's naturally selected traits is shown in this picture to be an evolutionary advantage?

coat color for blending in with dry grass

Veronica wrote Charles Darwin's main points on the board, but she made a mistake in one point. 1. Since more offspring are produced than an environment can support, organisms within a population must compete for resources to survive. 2. Due to variations within the population, some competitors will be better equipped for survival than others. 3. The best-equipped organisms will survive and will produce well-equipped offspring. 4. Variations that help with survival will be passed on to future generations and will rapidly change the whole population. Which point is flawed as written above?

Point 4

A population of white rabbits and brown rabbits both live in a temperate deciduous forest where the summers are mild and average about 50°F. The winters are often below freezing. If warmer temperatures last longer into the fall and the average temperature in the winter is getting warmer, what do you expect to happen to the population of each color of rabbit?

The brown rabbit population will thrive and reproduce, and the white rabbit population will slowly die out.

What is the best description of an organism that is fit for natural selection?

The organism is better able to survive and pass on traits to offspring than competing organisms.

A person with a genotype of HbSS has sickle cell disease. A person with a genotype of HbAS allele carries the sickle cell trait. A person with a genotype of HbAA does not have sickle cell disease and does not carry the trait. The Punnett square shows the genotype of two people carrying the sickle cell trait. What are the chances that their offspring will have sickle cell anemia?

25%

Scientific investigations often lead to the formulation of new scientific questions. The observations Charles Darwin made during his time aboard the H.M.S. Beagle prompted him to ask which question?

Do living organisms change over time and, if so, how?

Which statement would least likely be used to describe variation?

Variations that decrease reproductive success are more likely to be passed on.

The map shows the allele frequency of sickled hemoglobin (HbS) and malaria endemicity in Africa. Which statement best explains the relationship between HbS allele frequency and malaria endemicity in Africa?

When an area is malaria free, the HbS allele frequency is between 0 and 2.02.

Koalas are marsupials that are found in eastern Australia. Although their ancestors lived mostly on the ground, modern koalas spend most of their time in eucalyptus trees. This is possible because their hands and feet have strong claws and opposable digits. What other adaptation could have helped koalas as they evolved from land dwellers to tree dwellers?

fur color that closely matches the eucalyptus bark color