Darwin’s Theory of Evolution - Descebt with Modification

Question 1

What we’re Darwin’s general observations?

Answer 1

The rich diversity of life, the many shared characteristics (unity) of life, organisms are suited for their environment

Question 2

What are the two ways evolution can be viewed in?

Answer 2

As a pattern (observations of living world)
As a process (mechanisms that cause observed patterns)

Question 3

How did Aristotle use the word ‘evolution’?

Answer 3

He used ‘evolution’ in a descriptive sense, everything in nature having a certain order or purpose

Question 4

What we’re Aristotles contributions to to our understanding of evolution?

Answer 4

He classified all living organisms hierarchically and he made the Great Chain of Beings

Question 5

Why didn’t Aristotle address change over time?

Answer 5

He didn’t address change over time because he saw the universe as static and species fixed as they were

Question 6

What was the 1700’s conventional view of Earth and it’s life?

Answer 6

Most scientists accepted the views of the Greek philosopher Aristotle, who generally held that species are fixed, permanent forms that do not evolve
Judeo-Christian culture taught a literal interpretation of the biblical book of Genesis, that each form of life is individually created in its present-day form
Earlier religious scholars estimated the are of Earth at 6,000 years

Question 7

Who was Carl Linnaeus?

Answer 7

A botanist who sought to classify life’s diversity “for the greater glory of God”

Question 8

What was Carly Linnaeus contribution to the understanding of evolution?

Answer 8

He developed a heated classification system, grouping similar species into increasingly general categories - that classification system was: class, order, genus, and species

Question 9

Who was George Cuvier?

Answer 9

The founding fathers of paleontology - he was a geologist studying Paris stars and is know for his anatomical drawings

Question 10

Proponent of catastrophism

Answer 10

Sudden cataclysmic events and repopulation of sites by different immigrant species

Question 11

What is the complexifying force?

Answer 11

The idea that simple organisms were the product of spontaneous generation and that higher life forms were derived from simple forms via some kind of force that drive animals to become more complex over many generations

Question 12

What is the adaptive force?

Answer 12

The idea that life adapts to the changing conditions at the same time as it progresses up the chain of being and that characteristics are acquired as a result of effort are transmitted to the offspring

Question 13

What is the ‘Use and Disuse’ idea?

Answer 13

Parts of the body that are used extensively become better - these efforts during the life the individual would be passed to offspring (inheritance of acquired characters)

Question 14

What did many of Darwin’s observations indicate?

Answer 14

They indicated that geographic proximity is a better predictor of relationships among organisms that similarity of environment

Question 15

What did Darwin hypothesize about the organisms on the Galapagos Islands?

Answer 15

He hypothesized that species from South America had colonized the Galapagos and speculated on the islands

Question 16

What did the book Principles of Geology present?

Answer 16

It presented the case that changes in Earth’s surface can result from slow, continuous actions still operating today

Question 17

What we’re Darwin’s hypothesis’ about adaptation?

Answer 17

1- as the descendants of a remote ancestor spread into new habitats or their habitat changes, they accumulated diverse modifications, or adaptations, that fit them to specific ways of life in their environment
2- that present-day species are the descendants of ancient ancestors that they still resemble in some ways

Question 18

Did Darwin ever use the word ‘evolution’ in The Origin of Species?

Answer 18

No, he used the phrase ‘descent with modification’ to summarize his perception of the unity of life - the phrase refers to the view that all organisms are related through descent form an ancestor that lived in the remote past

Question 19

Why did some schools in America not want to teach evolution?

Answer 19

Because they believe evolution is only a theory

Question 20

Theory

Answer 20

In common usage: a theory is a conjecture, opinion or speculation that is not necessarily based on facts
In science: a theory is well-substantiated explanation of a set of natural phenomena

Question 21

What were the five lines of evidence for evolution?

Answer 21

Biogeography, fossil record, homologies: comparative anatomy and embryology, molecular biology, and direct observations

Question 22

Biogeographical evidence for evolution

Answer 22

Species tend to be more closely related to other species form the same area than to species with the same way of life from different area

Question 23

Fossils

Answer 23

The imprints or remains of organisms that lived in the past
Document differences between part and present organisms
Reveal that many species have become extinct

Question 24

Homologies evidence for evolution

Answer 24

Evolution is a process of descent with modification - a remodeling process

Characteristics present in an ancestral organism are altered over time by natural selection as its descendants face different environmental conditions

Related species can have characteristics that have an underlying similarity yet function differently

Question 25

Homology

Answer 25

Similarities resulting from common ancestry

Question 26

Homologous structures

Answer 26

Anatomical similarities on different organisms

Question 27

Vestigial structures

Answer 27

Remnants of features that served a function in the organism’s

Question 28

Do all forms of life use the same genetic language of DNA and RNA?

Answer 28

Yes, the genetic code is essentially universal

Question 29

Evolutionary tree

Answer 29

Has multiple branches from a common ancestral trunk to the descendant species at the tips of the twigs

Question 30

What homologous structures are used to determine the branching sequence of an evolutionary tree?

Answer 30

Anatomical structure and/or molecular sequence

Question 31

What are some examples of direct observation of evolutionary change?

Answer 31

Industrial melanoma in moths, the emergence of pesticide resistance in insects, and the appearance and then spread of new SARS-COV-2 variants

Question 32

What was Darwin’s greatest contribution to biology?

Answer 32

His explanation of how life evolves - his proposition of natural selection as the mechanism of evolution

Question 33

What two main observations brought Darwin to the conclusion that natural selection is how life evolves?

Answer 33

1- members of a population often vary in their inherited traits
2- all species can produce more offspring than the environment can support, and many of these offspring fail to survive and reproduce

Question 34

What is the essence of natural selection?

Answer 34

Unequal reproduction - individuals whose traits better enable them to obtain food or escape predators or tolerate physical conditions will survive and reproduce more successfully, passing these adaptive traits to their offspring

Question 35

What are three important points to emphasize about evolution by natural selection?

Answer 35

That individuals do not evolve, rather the population (group of organisms) evolves over time
That natural selection can amplify or diminish only heritable traits
That evolution is not goal directed, it results form environmental factors that vary temporally and spatially, traits that are beneficial one season may be detrimental the next