Chapter 4.2

Question 1

What is a scientific hypothesis?

Answer 1

A statement that provides a possible answer to a question

Question 2

How are hypotheses tested?

Answer 2

Experiments, observation, and developing models of data

Question 3

What is a scientific theory?

Answer 3

When hypotheses consistently lead to successful predictions and explanations are synthesized into a general statement that explains and makes predictions

Question 4

What is the theory of evolution by natural selection?

Answer 4

A well supported, widely accepted, explanation of how life has changed and continues to change during earth’s history

Question 5

What did Plato and Aristotle believe?

Answer 5

• That all life existed in a perfected and unchanging form.

- All species of organisms had been created independently of one another and had remained unchanged ever since.

Question 6

Who was the first person to challenger Aristotle and Plato?

Answer 6

French naturalist Georges-Louis Leclerc

Question 7

What did Georges-Louis Leclerc publish and what was it about?

Answer 7

A 44-volume Histoire Naturelle, which compiled his understandings of the natural world

Question 8

What did Georges-Louis Leclerc speculate?

Answer 8

That apes and humans were similar so, they must have a common ancestor and that earth was much older than 6000 years old

Question 9

Who developed the science of paleontology?

Answer 9

Georges Cuvier

Question 10

What is paleontology?

Answer 10

The study of ancient life through the examination of fossils

Question 11

What did Cuvier find in his paleontology?

Answer 11

• Each stratum (layer of rock) is characterized by a unique group of fossil species.
• The deeper (older) the stratum, the more different the species are from modern life

Question 12

What is a stratum?

Answer 12

A layer of rock

Question 13

What evidence shows that species can become extinct?

Answer 13

As you go from stratum to stratum you can see that species appeared and disappeared overtime

Question 14

What did Cuvier propose to explain his observations of species appearing and disappearing?

Answer 14

Cuvier proposed the idea that Earth experienced many destructive natural events, such as floods and volcanic eruptions, in the past. These were called revolutions

Question 15

What are revolutions?

Answer 15

Destructive natural events in the past that were violent enough to kill many species

Question 16

What did Charles Lyell believe in terms of destruction of species?

Answer 16

That geological processes operated at the same rates in the past as they do today

Question 17

What did Lyell theorize in terms of the earth’s changing?

Answer 17

• He proposed that geological processes operated at the same rates in the past as they do today.
• If geological changes are slow and continuous rather than catastrophic, then Earth might be more than 6000 years old.
• Lyell theorized that slow, subtle processes could happen over a long period of time and could result in substantial changes

Question 18

What inspired Charles Darwin?

Answer 18

Lyell’s hypothesis that slow changes can be substantial over long periods of time and that it could also work with populations

Question 19

What is a line of descent?

Answer 19

A progression, in which a series of fossils (from older to more recent) led to a modern species

Question 20

How was a line of descent created?

Answer 20

By comparing current species of animals with fossil forms

Question 21

What did Lamarck believe?

Answer 21

He thought that species increased in complexity over time, until they achieved a level of perfection

Question 22

What did Lamarck believe about the characteristic that could be passed down to offspring?

Answer 22

He thought that characteristics, such as large muscles, that were acquired during an organism’s lifetime could be passed on to its offspring. Ex. a large, powerful chest muscles of a horse would be passed on to its offspring, which would have the same characteristics

Question 23

What does inheritance of acquired characteristics mean?

Answer 23

The theory that characteristics acquired during an organism’s lifetime could be passed to its offspring

Question 24

Who else reach conclusions that were similar to Darwin’s?

Answer 24

Alfred Russel Wallace

Question 25

What did Darwin and Wallace agree on?

Answer 25

That populations changed as time passed, but they were unclear on how

Question 26

What did Malthus propose about populations?

Answer 26

He said that populations produce more offsrpring than their environments could support and were eventually reduced by starvation

Question 27

What organisms are more likely to survive in an environment?

Answer 27

Ones with physical, behavioral, and other traits that helped them to survive

Question 28

What would competition for resources within a species do?

Answer 28

Competition would select for those with favorable traits that increased their ability to survive and reproduce. This ensures that future populations also had these traits

Question 29

What 2 main ideas did Darwin propose in the “On the Origin of Species” essay?

Answer 29

1. Present forms of life have arisen by descent and modification from ancestral species
2. The mechanism for modification is natural selection working for long periods of time