Chapter 10

How do scientists use the term theory? as a hypothesis that has not yet been tested as a set of findings that are supported by repeated testing as ideas which are so obviously true that testing is not required as a hypothesis that seems logical but cannot be tested because it's impractical to do so

Which example describes biological evolution? Over time, a caterpillar species becomes as green as the leaves it eats. The average woman's dress size has increased over the last 50 years. You are vaccinated against polio and are protected against the disease. A tree branch is broken off and another grows in its place.

In the figure, what do the branching points of the tree represent? an extinct species the origin of a new species from an ancestral form a common ancestor of a group of modern species a modern species

Why can evolution in mosquitoes be more easily observed than evolution in a population of squirrels? Mosquitoes feed only on blood. Mosquitoes have a shorter generation time. Mosquitoes lay eggs rather than bear live young. Mosquitoes have a higher mutation rate.

According to the theory of common descent, how should each species on Earth today compare? They should have a single ancestor in common. They should not have ancestors in common with members of other species. They should look very similar to all other species. They should have DNA that is mostly unique from other species.

What was the original purpose of the voyage of the HMS Beagle? to chart the coast and harbors of South America to do experiments to test Lamarck's view of inheritance of acquired characteristics to add to the general knowledge of the animals and plants on Earth to gather physical evidence in support of the theory of evolution

What aspect of the geology of the Galápagos was important in producing the diversity of organisms seen by Darwin? The islands are very dry. The islands are in the Pacific. The islands are in a chain. There are no mammals on the islands.

How did Wallace contribute to the history of ideas about evolution? He was the main opponent of Darwin's ideas immediately after they were published. He proposed the idea that Earth is very old. He proposed the theory of inheritance of acquired characteristics. He proposed a theory of evolution similar to Darwin's.

Why were Darwin's ideas so widely accepted by scientists of his day? Darwin presented extensive evidence from many areas of biology to support his ideas. Darwin was from a rich and powerful family. He published his book soon after he returned to England, and all his recollections were fresh in his mind. Darwin's ideas fit well with what most people already understood about evolution.

What characteristics would determine whether structures from two kinds of organisms are homologous? The structures should have identical functions in both organisms. The structures should have similar anatomy in the two organisms. The structures should be in different positions on the bodies of the two organisms. The structures should not appear in any close relatives of the organisms.

How do fossils support the theory of common descent? They contain complete DNA genomes, so they can be compared to modern organisms. They are found equally all over the world, so they explain all our questions about biogeography. They are a record of some intermediate types of organisms that document the process of evolution. They can be easily and precisely dated by comparing the rock layers where they are found.

Why would the DNA of cats and dogs be much more similar than the DNA of cats and hamsters? Cats and dogs have fewer offspring during their lifetime than hamsters, so their DNA changes less rapidly. Cats and dogs have a more recent common ancestor than the common ancestor of cats and hamsters. Cats and dogs have lived together with humans for a longer time and have become more similar. The ancestors of cats and the ancestors of dogs evolved in similar environments.

Why is common descent considered a scientific theory? There is overwhelming evidence to support it from many areas of biology. It's the only idea about life on Earth that can be tested by observation of the material universe. It's an idea from more than 100 years ago and thus is not a modern idea. Scientists are reasonably sure it's true, but there's little evidence to support it.

Bat wings are homologous to the front legs of cats. What does the term homologous mean in this context? The common ancestor of bats and cats had limbs that functioned as wings. The common ancestor of bats and cats had a limb with a bone structure similar to that found in cat legs and bat wings. Both structures are used for the same purpose. Bat wings are vestigial legs.

Which observations of species distribution across Earth support the theory of common descent? All continents contain nearly identical organisms. Each part of Earth contains life forms perfectly designed for that region. One can see similarities in organisms that are found in close proximity, but each population has adaptations that suit the organisms to their particular habitat. There are very few similarities among life forms on different tropical islands.

Which vestigial structure found in humans is best explained by our evolutionary heritage? upright posture lack of body hair tailbone

What type of evidence for the theory of common descent would include the presence of goose bumps in humans? vestigial structures DNA similarity shared developmental pathways homologous structures

Why is the separate types hypothesis considered so unlikely by most biologists? There are multiple similarities in all life at the cellular level that strongly suggest a common origin for all living things. The separate types model hypothesizes many changes in living things over time, while the fossil record suggests that few of these changes have occurred. The similarity in appearance in many living things suggests that there must have been only one common ancestor. If different types of life evolved independently, it would be obvious in the fossil record.

Which hypothesis was rejected by the evidence from radiometric dating of non-fossil rocks? separate type hypothesis transformation hypothesis static hypothesis common descent hypothesis

What does the presence of a tail in early human embryos and other chordates suggest about all chordates? Chordates may eventually develop a tail when fully mature. Chordates develop in a very different manner compared to other life forms. Chordate embryos have greater mutation rates than other organisms. Chordates were derived from a common ancestor with this developmental pathway.

Change in the characteristics of a population of organisms that occurs over the course of generations

Definition of natural selection process by which populations adapt to their changing environment

changes that occur within a biological population

Pesticide resistancein crop-eating insects Antibiotic resistancein infectious bacteria Examples of....

large-scale evolutionary changes that result in the origin of new species Occurs slowly over long periods of time

tentative explanation with little support

statement providing the current best explanation of how the universe works Supported by many lines of evidence

•Atomic theory •Germ theory of disease •Gravitational theory •Theory of relativity Are examples of....

Where did ancient hominins first evolve from a common ancestor? A.North America B.Europe C.Africa D.Galapagos Islands

the remains of living organisms left in soilor rock