UNIT VChapter 15 Darwin’s Theory of

Evolution

I. Darwin’s Theory of Evolution (theory-well supported explanation of phenomena

that have occurred in the natural world. Evolution- change over time- (microevolution vs. macroevolution) process by which organisms have descended from ancient organisms

A. The Puzzle of Life’s Diversity

1. Voyage of the Beagle (1831)- Charles Darwin (born 1809) set sail around the world as naturalist to collect organisms and make observations

2. Darwin’s observations- observed great diversity of organisms. Puzzled by variety.

a. Living organisms and fossils- observed remains of ancient organisms (fossilsfossils). Started to pose questions?

b. Galápagos Islands- This stop influenced Darwin the most. Realized that habitat determined physical characteristics of organism that lived there. Varied from island to island

3. The Journey Home- spent time reviewing his findings. He had collected thousands of specimens, fossils, pages of notes

B. Ideas that shaped Darwin’s thinking- numerous discoveries had turned up important pieces of evidence challenging traditional view of life.

1. An Ancient, Changing Earth- scientist beginning to discover Earth is very old.

a. James Hutton (1795)- geologist said slow processes shaped mountains, valleys, rocks (millions of years)

b. Charles LyellCharles Lyell- book “Principles of Geology” greatly influenced Darwin. Said scientists must explain past events in terms of processes they can actually observe (same processes still shaping the Earth today). Darwin thought “If Earth can Darwin thought “If Earth can change over time, might life change as change over time, might life change as well”well”

2. Lamarck’s Theory of Evolution- among first scientist to recognize living things change over time- also realized that organisms adapted to their environment.

a. Theory stated- by selective use or disuse of organs, organisms acquired certain traits during their lifetime. These traits could be passed on to offspring

1). Tendency towards perfection- said organisms have innate tendency toward complexity and perfection2). Theory incorrect in several ways- important because paved way for work of other biologists

3. Population growth- Thomas Thomas MalthusMalthus- said crowding, over population, and disease limited the growth of populations. Darwin realized that this applied to plants and animals- overwhelming majority of overwhelming majority of species offspring die species offspring die

C. Darwin presents his case

1. Publication of “On the Origin of SpeciesOn the Origin of Species” (1859)

a. Spent 25 years going over data and observationsb. Proposed mechanism for evolution- called natural selection- survival of the fittestnatural selection- survival of the fittest

2. Darwin’s explantation

a. Natural variationNatural variation- said variation present in all types of organisms

b. Artificial selectionArtificial selection- study of English farmers and breeders led to some of Darwin’s greatest progresses towards macroevolutionary theory

Artificial selectionArtificial selection- humans select from among the naturally occurring variations in a species. This can lead to great differences (labs vs. poodles)

c. Evolution by Natural Selection- Darwin’s hypothesis to explain how evolution occurs

1). The struggle for existence- members from each species compete for food, living space, other necessities of life.

2). Survival of the FittestSurvival of the Fittest- individuals better suited to their environment survive and reproduce most successfully. (Over time, natural selection causes a change in inherited characteristics of a population) Does that mean the traits for not being “fit” are lost?

Before the industrial revolution, soot was rare in the English countryside. A light-colored moth was difficult to see against the clean bark. Incidentally a hoax.

Which moth would most likely be noticed by a hungry bird?

3). Descent with ModificationDescent with Modification- Darwin proposed that over long periods of time natural selection produces organisms with different structures that occupy different niches or habitats.

4). Common DescentCommon Descent –All of these things imply that there is a “tree of lifetree of life” that links all living things on Earth

3. Evidence of Evolution-

a. Fossil RecordFossil Record- fossil evidence in different layers of rock showed gradual change over time.

Youngest fossilsYoungest fossils

Oldest fossilsOldest fossils

b. Geographic distributionGeographic distribution of living species- similar organisms in different locations were product of different lines of evolutionary descent.

Similar ecological conditions- similar pressures of natural selection

c. Homologous body structuresHomologous body structures- structural features with common evolutionary origins

d. Vestigial structuresVestigial structures- some homologous structures no longer serve important function. Reduced in size (“vestiges”)

Forelimbs of extinct elephant bird are vestigial structures

e. Similarities in Early developmentSimilarities in Early development- similarities suggest an evolutionary relationship

Gill pouches and tails appear during early stages- remnants of structures needed by our aquatic ancestors.

During later stages- profound changes occur.

f. BiochemistryBiochemistry- similarities in DNA and RNA help to determine evolutionary relationships between species

Chimp chromosomes (24 pair) Human chromosomes (23 pair)

Chapter 15 Darwin’s

Theory of Evolution

During the voyage of the Beagle, many of Darwin's observations were made

a. in England.

b. in North America.

c. on the Galápagos Islands.

d. in Africa.

During the voyage of the Beagle, many of Darwin's observations were made

a. in England.

b. in North America.

c. on the Galápagos Islands.

d. in Africa.

The species of finches that Darwin found on the Galápagos Islands displayed different structural adaptations. One of the adaptations that Darwin noted was the

a. similarities of the birds' embryos.

b. birds' differently shaped beaks.

c. length of the birds' necks.

d. number of eggs in each bird's nest.

The species of finches that Darwin found on the Galápagos Islands displayed different structural adaptations. One of the adaptations that Darwin noted was the

a. similarities of the birds' embryos.

b. birds' differently shaped beaks.

c. length of the birds' necks.

d. number of eggs in each bird's nest.

Hutton and Lyell's work suggested that

a. Earth is millions of years old.

b. Earth is several thousand years old.

c. fossils are not the remains of living things.

d. all rocks on Earth contain fossils.

Hutton and Lyell's work suggested that

a. Earth is millions of years old.

b. Earth is several thousand years old.

c. fossils are not the remains of living things.

d. all rocks on Earth contain fossils.

Hutton and Lyell's work was important to Darwin because it

a. was the first to attempt to explain catastrophic events such as earthquakes.

b. completely explained the nature of all geologic events on Earth.

c. suggested that Earth was old enough for evolution to have occurred.

d. refuted the work of Wallace, which relied on misunderstandings about geology.

Hutton and Lyell's work was important to Darwin because it

a. was the first to attempt to explain catastrophic events such as earthquakes.

b. completely explained the nature of all geologic events on Earth.

c. suggested that Earth was old enough for evolution to have occurred.

d. refuted the work of Wallace, which relied on misunderstandings about geology.

Which is a major concept included in Lamarck's theory of evolution?

a. Change is the result of mutations.

b. Body structure can change according to the needs of the organism.

c. Selection pressures decrease the rate of evolution.

d. Sexual reproduction is the genetic basis for variations.

Which is a major concept included in Lamarck's theory of evolution?

a. Change is the result of mutations.

b. Body structure can change according to the needs of the organism.

c. Selection pressures decrease the rate of evolution.

d. Sexual reproduction is the genetic basis for variations.

The economist Malthus suggested that

a. people die faster than babies are born.

b. babies are born faster than people die.

c. in the 1700s, Earth was overrun by people.

d. in the 2000s, the seas will be overrun by oysters.

The economist Malthus suggested that

a. people die faster than babies are born.

b. babies are born faster than people die.

c. in the 1700s, Earth was overrun by people.

d. in the 2000s, the seas will be overrun by oysters.

Darwin was prompted to publish his theory of evolution by

a. an essay by Wallace on evolution.

b. the publication of Lamarck's theory of evolution.

c. the vice governor of the Galápagos Islands.

d. his wife.

Darwin was prompted to publish his theory of evolution by

a. an essay by Wallace on evolution.

b. the publication of Lamarck's theory of evolution.

c. the vice governor of the Galápagos Islands.

d. his wife.

When Darwin returned from the voyage of the Beagle, he

a. immediately publish his theory of evolution.

b. realized his theory of evolution was wrong.

c. waited many years to publish his theory of evolution.

d. copied the evolutionary theory of Wallace.

When Darwin returned from the voyage of the Beagle, he

a. immediately publish his theory of evolution.

b. realized his theory of evolution was wrong.

c. waited many years to publish his theory of evolution.

d. copied the evolutionary theory of Wallace.

When a farmer breeds only his or her best livestock, the process involved is

a. natural selection.

b. artificial selection.

c. artificial variation.

d. survival of the fittest.

When a farmer breeds only his or her best livestock, the process involved is

a. natural selection.

b. artificial selection.

c. artificial variation.

d. survival of the fittest.

According to Darwin's theory of natural selection, individuals who survive are most likely the ones best adapted to exist in their environment. Their survival is due to the

a. possession of structures developed through use.

b. possession of adaptations that maximize fitness.

c. lack of competition within the species.

d. ability to change their genotype.

According to Darwin's theory of natural selection, individuals who survive are most likely the ones best adapted to exist in their environment. Their survival is due to the

a. possession of structures developed through use.

b. possession of adaptations that maximize fitness.

c. lack of competition within the species.

d. ability to change their genotype.

An adaptation is a characteristic that can be physical or

a. behavioral.

b. geographical.

c. acquired.

d. that does not affect fitness.

An adaptation is a characteristic that can be physical or

a. behavioral.

b. geographical.

c. acquired.

d. that does not affect fitness.

When lions prey on a herd of antelope, some antelope are eliminated. Which part of Darwin's theory of evolution may be used to describe this situation?

a. acquired characteristics

b. reproductive isolation

c. survival of the fittest

d. speciation due to mutations

When lions prey on a herd of antelope, some antelope are eliminated. Which part of Darwin's theory of evolution may be used to describe this situation?

a. acquired characteristics

b. reproductive isolation

c. survival of the fittest

d. speciation due to mutations

According to Darwin's theory of natural selection, the individuals that tend to survive are those that have

a. characteristics their parents acquired by use and disuse.

b. undergone mutations.

c. the smallest number of offspring.

d. variations best suited to the environment.

According to Darwin's theory of natural selection, the individuals that tend to survive are those that have

a. characteristics their parents acquired by use and disuse.

b. undergone mutations.

c. the smallest number of offspring.

d. variations best suited to the environment.

What is evolution?

a. the increased reproductive success of the fittest individuals

b. the diminished reproductive success of poorly adapted individuals

c. the change in the inherited characteristics of a population

d. the struggle for existence undergone by all living things

What is evolution?

a. the increased reproductive success of the fittest individuals

b. the diminished reproductive success of poorly adapted individuals

c. the change in the inherited characteristics of a population

d. the struggle for existence undergone by all living things

The pelvis and femur of the whale shown in Figure _____________.

a. allow the whale to walk.

b. are vestigial structures.

c. are acquired traits.

d. are not inherited.

The pelvis and femur of the whale shown in Figure _______________.

a. allow the whale to walk.

b. are vestigial structures.

c. are acquired traits.

d. are not inherited.

The observation by Darwin that finches of different species on the Galápagos Islands have many similar physical characteristics supports the conclusion that these finches

a. have the ability to interbreed.

b. acquired traits through use and disuse.

c. all eat the same type of food.

d. originated from a common ancestor.

The observation by Darwin that finches of different species on the Galápagos Islands have many similar physical characteristics supports the conclusion that these finches

a. have the ability to interbreed.

b. acquired traits through use and disuse.

c. all eat the same type of food.

d. originated from a common ancestor.

The number and location of bones of many fossil vertebrates are similar to those in living vertebrates. Most evolutionary biologists would probably explain this on the basis of

a. the needs of the organism.

b. a common ancestor.

c. a chance occurrence.

d. the inheritance of acquired traits.

The number and location of bones of many fossil vertebrates are similar to those in living vertebrates. Most evolutionary biologists would probably explain this on the basis of

a. the needs of the organism.

b. a common ancestor.

c. a chance occurrence.

d. the inheritance of acquired traits.

The theory that organisms evolve, or change, over time by natural selection was proposed by

a. Hutton.

b. Lamarck.

c. Malthus.

d. Darwin.

The theory that organisms evolve, or change, over time by natural selection was proposed by

a. Hutton.

b. Lamarck.

c. Malthus.

d. Darwin.

Which statement is in agreement with Darwin's theory of evolution?

a. More offspring are produced than can possibly survive.

b. The organisms that are the fittest are always largest.

c. Number of offspring is not related to fitness.

d. Acquired characteristics are inherited.

Which statement is in agreement with Darwin's theory of evolution?

a. More offspring are produced than can possibly survive.

b. The organisms that are the fittest are always largest.

c. Number of offspring is not related to fitness.

d. Acquired characteristics are inherited.

Which phrase best defines evolution by natural selection?

a. an adaptation of an organism to its environment

b. a sudden replacement of one community by another

c. a geographic or reproductive isolation of organisms

d. a process of change in organisms over a period of time

Which phrase best defines evolution by natural selection?

a. an adaptation of an organism to its environment

b. a sudden replacement of one community by another

c. a geographic or reproductive isolation of organisms

d. a process of change in organisms over a period of time

The following dog breeds were produced by the process known as ______________.

The following dog breeds were produced by the process known as artificial selection

The diagram below represents what type of structures?

The diagram below represents what type of structures?

Homologous structures

What is the name of the book in which Charles Darwin presented his theory of evolution?

What is the name of the book in which Charles Darwin presented his theory of evolution?

The Origin of Species