Evolution

(5.1) Snakes such as boa constrictors and pythons have tiny leg bones buried in their muscles. These leg bones are vestigial structures that have little or no known function in snakes. Which best explains the presence of these vestigial structures in snakes?

• Snakes evolved from organisms with legs.

• Snakes are developing legs for walking on land.

• Snakes born with an extra set of DNA develop legs as they mature.

• Snakes have only one copy of the allele for legs in their chromosomes.

(5.1) For many years, biologists disagreed about whether giant pandas are more closely related to raccoons or bears. Which of the following types of evidence was most useful in determining the evolutionary relationship of giant pandas to other animals?

• diet

• behavior

• genetic sequences

• anatomical features

(5.1) Which of the following observations most strongly supports evolutionary links between fossil organisms and modern organisms?

• The fossil organisms and modern organisms have identical body sizes.

• The fossil organisms and modern organisms have homologous body structures.

• The fossil organisms are hundreds of thousands of years old, and modern organisms have been around for hundreds of years.

• The fossil organisms are found in many different rock layers, and modern organisms live in many different habitats.

(5.1) A scientist is trying to determine how closely related two species of plants are. Which of the following would be most useful for the scientist to compare?

• the root depths of the plants

• the leaf structures of the plants

• the genetic sequences of the plants

• the nutrient requirements of the plants

(5.1) The illustrations show the embryos of a fish, a reptile, and a bird at the same stage of development. Which of the following can be concluded from the illustrations?

• All the embryos grow at the same rate.

• All the embryos will develop identical structures.

• All the organisms share a recent common ancestor.

• All the organisms will be the same relative size as adults.

(5.1) Which of the following provides the weakest scientific evidence that two species have a common ancestor?

• comparing fossils

• comparing food sources

• comparing genetic information

• comparing homologous structures

(5.1) The forelimbs of a whale and an alligator have a similar structure. Which of the following statements best explains this similarity in structure?

• The whale and the alligator evolved at the same time.

• The whale and the alligator have a recent common ancestor.

• The whale and the alligator spend all of their time in the water.

• The whale and the alligator have the same method of locomotion.

(5.1) The pictures show the shells of some species of land snails found on a Pacific island. Each species was found on a different hill on the island. Based on the snails’ shell shapes, scientists made hypotheses about the evolutionary relationships among the snails. Which of the following would be the best characteristic to compare in order to test these hypotheses?

• the size of the snails

• the diet of the snails

• the DNA of the snails

• the average age of the snails

(5.1) In Australia, some native bugs eat the large fruit of an invasive plant by making a hole in the fruit’s thick skin with their mouthparts. The table shows data that scientists collected about the bugs before and after the invasive plants were introduced. In Australia, some native bugs eat the large fruit of an invasive plant by making a hole in the fruit’s thick skin with their mouthparts. The table below shows data that scientists collected about the bugs before and after the invasive plants were introduced.

• The bugs are unable to feed on native fruits.

• Bugs with shorter mouthparts have all died off.

• Bugs with longer mouthparts have a survival advantage.

• The bugs have started cross-breeding with a larger species.

(5.1) Which of the following statements provides the best scientific evidence that chimpanzees and rhesus monkeys come from a common ancestor?

• They live in similar habitats.

• They exhibit similar behaviors.

• They have similar nutritional needs.

• They have similar genetic sequences.