7.1 Steps Leading Up To Charles Darwin's Theory

Question 1

What is a theory?

Answer 1

a set of statements that explains a group of facts or phenomenons

Question 2

Who was the “father” of evolutionary thought?

Answer 2

Charles Darwin

Question 3

Darwin developed a theory to explain _____?

Answer 3

-The diversity of Life on Earth
-How all organisms are related to one another
-How all organisms are related to the environments
they live in

Question 4

What is evolution?

Answer 4

the biological history of life on Earth and the process by which organisms change (evolve) over time

Question 5

Before Darwin’s time, what were the 2 main ideas of the natural world?

Answer 5

1) Species were fixed, did NOT change over time
(immutable)

2) Earth is less than 10, 000 years old (young) and
relatively unchanging

Question 6

Who decided that living things had been created in their present forms and were immutable?

Answer 6

Aristotle

(he developed this theory through strongly held religious beliefs)

Question 7

Who was the first to challenge the belief that the earth was young and supported uniformitarianism?

Answer 7

James Hutton

Question 8

What is uniformitarianism?

Answer 8

a theory that stated that the Earth was formed entirely by slow-moving processes, such as erosion and
sedimentation, and that these slow forces continue to shape the landscape

Question 9

What did James Hutton conclude from his findings?

Answer 9

Concluded the Earth took millions of years (not thousands), to form the current landscape.

Question 10

Who was the “father” of Modern Day Geology?

Answer 10

Charles Lyell

Question 11

What is geology?

Answer 11

the study of Earth’s physical structure

Question 12

Who Popularized and expanded on Hutton’s idea of uniformitarianism?

Answer 12

Charles Lyell

Question 13

What are the principles of uniformitarianism?

Answer 13

1) Earth has been changed by the same processes in the past that are occurring in the present

2) Geological change is slow and gradual

3) Natural laws that influence these changes are constant and eternal, and they operated in the past with the same intensity they do today

Question 14

Why were Lyell’s ideas radical at the time?

Answer 14

Because his theories directly challenged the belief in a very young Earth

Question 15

What was James Cuvier?

Answer 15

a paleontologist

Question 16

What is paleontology?

Answer 16

The study of fossil organisms to learn about prehistoric life

Question 17

What did Cuvier find?

Answer 17

-Compared fossils of modern day elephants to mammoths
-Concluded that some organisms had become extinct over time (e.g. Mammoths, Dinosaurs)

Question 18

Where can you find the fossils of very simple organisms?

Answer 18

Fossils of very simple organisms are found in ALL depths of fossil deposits

Question 19

Where can you find the fossils of complex organisms located?

Answer 19

Fossils of more complex organisms are found only at shallower depths, in younger rock

Question 20

What are fossils in the shallower depths more likely to resemble?

Answer 20

Fossils in the shallower depths are more likely to resemble living species

Question 21

True or False: Rock layers contain fossils of many species that do not occur in layers above or below them

Answer 21

True

Question 22

In only which rock can you find fossils?

Answer 22

sedimentary rock

Question 23

What did fossil observation help us to discover?

Answer 23

Fossil observation offered strong support that life evolved from simple to complex

Question 24

What is catastrophism?

Answer 24

a theory that global catastrophes, such as floods, caused the widespread extinctions of species

Question 25

Who believed that species themselves did not change and that these species were then replaced with another newly created set of species

Answer 25

Cuvier

Question 26

Who applied scientific methods to the detailed study of anatomy and studied animal structures, considering their functions?

Answer 26

Buffon

Question 27

Who was the "father" of taxonomy?

Answer 27

Carolus Linnaeus

Question 28

Who proposed that life changed over time?

Answer 28

Linnaeus

Question 29

Who was Erasmus Darwin?

Answer 29

Charles Darwin's grandfather

Question 30

Who suggested that life might have evolved from a single original source?

Answer 30

Erasmus Darwin

Question 31

Who was a student of Buffon?

Answer 31

Lamarck

Question 32

Who was the first to offer a mechanism for the evolution of a species?

Answer 32

Lamarck

Question 33

Who explained evolution as a process of adaptation?

Answer 33

Lamarck

Question 34

What is adaptation?

Answer 34

An inherited characteristic that improves an organism's ability to survive and reproduce in an environment

Question 35

Who was the first to propose a hypothesis to explain how changes in species happen?

Answer 35

Lamarck

Question 36

What was Lamarck's first principle?

Answer 36

Use and Disuse Believed that structures an individual used became larger and stronger while structures that were not used become smaller and weaker E.g. Ducks strain their toes to swim, and thereby develop webbed feet and penguins’ wings shrink since they don’t use them to fly

Question 37

What was Lamarck's second principle?

Answer 37

Inheritance of Acquired Characteristics Believed that individuals could pass down characteristics they acquired during their lives E.g. if an adult giraffe stretched its neck during its lifetime, then its offspring would be born with slightly longer necks

Question 38

What was Lamarck's third principle?

Answer 38

Tendency Towards Perfection Organisms continually (willingly) change and acquire features in order to be more successful in their environments

Question 39

What significant contributions did Lamarck make to our understanding of evolution?

Answer 39

1) All species evolve over time 2) A species evolve in response to its environment and becomes better adapted to that environment 3) Changes are passed on from generation to generation

Question 40

What was the evidence that scientists began to find to contradict a young earth?

Answer 40

fossils

Question 41

What are fossils?

Answer 41

-preserved remains of organisms -the closer to the surface, the more recent the ancestor

Question 42

What are the 3 patterns of diversity that Darwin observed on his voyage?

Answer 42

1) Species vary globally 2) Species vary locally 3) Species vary over time

Question 43

Describe Darwin's first observation: species vary globally

Answer 43

-unrelated species look/behave similarly if they occupy similar environments ex. African ostrich, South American rheas and Australian emus -some organisms are unique to certain areas ex. kangaroos -organisms within a continent (e.g. Australia) can show physical uniqueness when compared to other continents

Question 44

Describe Darwin's second observation: species vary locally

Answer 44

-organisms that occupy different habitats, look different Ex. Galapagos islands -each island has different climates and there are different turtles on different islands that are adapted to feed differently, depending on available vegetation/geography Ex. Darwin’s Finches had differently shaped bills according to their feeding patterns -noticed species on islands looked very similar to species on mainland

Question 45

Describe Darwin's third observation: species vary over time

Answer 45

-Studied fossils and noticed patterns -Some were gigantic versions of modern-day animals such as the armadillo -Others had no currently living counterparts -Brought up the question as to “what had happened to cause the extinction of those species?”

Question 46

Applying Lyell’s ideas, who reasoned that earthquakes gradually lifted rock containing marine fossils from the sea floor?

Answer 46

Darwin

Question 47

What did Darwin apply the idea of gradual change to?

Answer 47

the evolution of Earth’s life forms

Question 48

What ideas from geology were important in developing the theory of evolution?

Answer 48

uniformitarianism -which stated that Earth was formed entirely by slow-moving processes, such as erosion and sedimentation, and that these slow forces continue to shape the landscape. -Earth was many millions of years old, and the processes that changed the Earth in the past were the same processes that operate in the present.

Question 49

How did Lamarck propose that species evolve?

Answer 49

-he proposed that species evolve, or change, over time -he explained evolution as a process of adaptation organisms altered their behavior in response to environmental change -their changed behavior, in turn, modified their organs, and their offspring inherited those "improved" structures

Question 50

What parts of Lamarck’s hypotheses have been proved wrong?

Answer 50

-organisms do NOT have an inborn drive to become more perfect -evolution does NOT progress in a predetermined direction -traits acquired by individuals during their lifetime CAN'T be passed on to offspring

Question 51

What did Lamarck get right?

Answer 51

his most correct assumption was the importance of environmental changes on evolutionary adaptations

Question 52

What was Malthus’s view of population growth?

Answer 52

-Malthus contended that much of human suffering was due to the human population’s potential to grow -That is, populations can grow much faster than the rate at which supplies of food and other resources can be produced -Too many people and too few resources lead to war, disease, and famine

Question 53

What three patterns did Darwin observe during his voyage on the HMS Beagle?

Answer 53

-species vary globally -species vary locally -species vary over time

Question 54

How would Lyell explain the formation of the Grand Canyon?

Answer 54

He would use the uniformitarianism theory and would say that slow-moving processes, such as erosion and sedimentation shaped the landscape The rock layers in the Grand Canyon were laid down over millions of years and were then slowly washed away by the river, forming a channel

Question 55

Suggest how the ideas of a changing Earth and evolving life forms might be related

Answer 55

-Evolution changes with a changing Earth -The fact that Earth can change over time inspired the idea that organisms can also change -Earth's great age makes it possible for significant changes to have occurred.

Question 56

Why are Lamarck’s ideas called scientific hypotheses and not scientific theories?

Answer 56

1. A hypothesis is a possible explanation for a set of observations or possible answer to a scientific question 2. A theory is a well-tested explanation that unifies a broad range of observations and hypotheses

Question 57

Suppose a chain of volcanic islands has just been discovered in the Atlantic ocean, 1000 km off the west coast of Africa. Each island has a different climate and terrain. Predict the kinds of organisms that you might find on the various islands. Justify your predictions

Answer 57

species vary locally -organisms that occupy different habitats will look different -the species on islands will look very similar to species on mainland

Question 58

A cave salamander is blind. (Its eyes are non-functional.) (a) How would Lamarck explain how this inability evolved from sighted ancestors?

Answer 58

He would say the trait was passed down from its ancestor -believed that individuals could pass these acquired traits on to their offspring, enabling species to change over time

Question 59

A cave salamander is blind. (Its eyes are non-functional.) (b) Can you think of an alternative explanation?

Answer 59

He also believed that organisms could change during their lifetimes by selectively using or not using various parts of their bodies... since these salamanders lived in caves, they might not have needed to use their eyes.

Question 60

Suppose a young man works as a construction worker loading bags of cement onto trucks and he becomes very strong. If Lamarck’s hypothesis of use and disuse were correct, would the man’s offspring also be strong? Explain

Answer 60

The man's offspring would be strong if they had jobs that required strength and they were using it every day because Lamarck's hypothesis states that traits an individual uses becomes larger and stronger while traits that are not used become smaller and weaker.

Question 61

Why is studying islands, such as the Galapagos Islands, so important in our understanding of the diversity of life?

Answer 61

-represent the biogeography and climate zones of the world, and therefore demonstrates a high diversity of different phylogenetic lineages from all continents -islands are also repositories of genetic information whose present-day biodiversity stands as a record of millions of years of evolution

Question 62

Explain the difference between a theory and a hypothesis.

Answer 62

A hypothesis is an assumption made before any research has been done. It is formed so that it can be tested to see if it might be true. A theory is a principle formed to explain the things already shown in data.

Question 63

Describe two or three challenges scientists encounter while developing a scientific theory.

Answer 63

1) Make the theory (set of statements that explain a group of facts or phenomena) 2) They have to test it repeatedly and support it with evidence 3) Their theory is just a prediction so it could be wrong and they would have to start the process all over again

Question 64

Paleontologists have discovered the fossilized remains of ancestors of whales in Pakistan. These remains were found far from any large body of water. What can you infer from this observation?

Answer 64

-whales didn't always live in water -they could have had legs and didn't use them so according to Lamarck's principle, "use and disuse" and "tendency towards perfection", they must have not used their legs often, spent more time in water and grew flippers and blubber to adapt to their new environment -therefore, they could have evolved into aquatic animals

Question 65

Darwin observed unique species in some parts of the world. Do you think that modern travel has affected the distribution of species around the world? Justify your answer.

Answer 65

? yes: -invasive species -tourism causes endangered species -tourism damages the environment and animal habitats, forcing species to leave

Question 66

If an alien species visited Earth to examine its biodiversity, would they draw the same conclusions about species distribution as Darwin did?

Answer 66

? no: -species have evolved since then and certain factors have caused species to relocate and leave their habitats -the concept of "the production of more individuals than the environment can support leads to a struggle for existence" could be used to explain how some species went extinct, so species distribution isn't the same as it was