Activity 4

Darwin and the Development of a Theory

Activity 4: Darwin and the Development

of a Theory

LIMITED LICENSE TO MODIFY. These PowerPoint® slides may be modified only by teachers currently teaching the Science and Global Issues SEPUP course to customize the unit to match their students’ learning levels or to insert additional teaching aides. Modified slides may be used only by the modifying teacher in his or her classroom, or shared with other teachers of Science and Global Issues within the teacher’s school district, with these same restrictions. Modified slides may not be taken out of the classroom or distributed to any non-student person or organization. Except for use with students in the classroom, modified slides may not be published in printed or electronic form, including posting on the Internet. Only text may be modified: photographs and illustrations on the slides may not be modified in any way except to change their size.

DISCLAIMER OF WARRANTY. THE REGENTS OF THE UNIVERSITY OF CALIFORNIA (“University”) MAKE NO REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. University will not be liable for any costs, damages, fees or other liability, nor for any direct, indirect, special, incidental or consequential damages (including lost profits) with respect to any claims by the purchaser or user of Science and Global Issues or any third party on account of or arising from the use or modifications to the slides. Client acknowledges and accepts that University services are provided on an as-is basis.

Activity 4: Darwin and the Development

of a Theory

Introduction

Biological evolution or evolution is a change in the genetic composition of a population that gives rise to new life forms from common ancestors.

Read the Introduction.

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

How did Darwin build on his and others’ work to develop his ideas about natural selection and evolution?

Challenge

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

Procedure

Activity 4: Darwin and the Development

of a Theory

Follow Up

Heritablevariation

Natural Selection and Evolution

+

Competition for environmental

resources needed for

survival

Differential reproduction

Changes in populations over time

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

How did Darwin build on his and others’ work to develop his ideas about natural selection and evolution?

Revisit the Challenge

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

An Essay on the Principle of Population: Malthus states increasing human population will need more food than available.

Zoological Philosophy: Lamarck suggests evolution occurs in an individual organism—some organs used more, some less.Darwin is born.

Principles of Geology: Lyell discusses the great age of the Earth, how small changes over long periods lead to change on a grand scale.

Timeline of Ideas Leading Up To and Following Darwin’s Work

1798

1809

1830

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

Darwin joins the voyage of the H.M.S. Beagle as naturalist, reads Lyell’s first volume.

H.M.S. Beagle returns. Naturalists help Darwin catalog his specimens. Farmers and pigeon breeders describe to him their efforts to improve crops and animals

Sketch on Natural Selection: Darwin’s initial version of his theory of evolution; made public many years after his death.

Timeline of Ideas Leading Up To and Following Darwin’s Work, cont.

1831

1836

1842

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

Alfred Wallace comes to the same conclusion as Darwin: natural selection is a driving force behind evolution. Linnaean Society presents the men’s work together.

On the Origin of Species: Darwin explains his theory of evolution by natural selection.

Austrian monk Gregor Mendel proposes the Laws of Heredity, based on his work with peas, mostly unnoticed until nearly 1900.

Timeline of Ideas Leading Up To and Following Darwin’s Work, cont.

1858

1859

1866

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

Thomas Hunt Morgan’s work on eye color in fruit flies reveals the mechanism of mutation, the source of genetic variation.

Systematics and the Origin of Species: Ernst Mayr gives examples of geographic isolation and how it leads to speciation.

Francis Crick, Rosalind Franklin, and James Watson discover the structure of DNA.

Timeline of Ideas Leading Up To and Following Darwin’s Work, cont.

1900

1942

1953

Activity 4: Darwin and the Development

of a Theory

Activity 4: Darwin and the Development

of a Theory

biological evolution evidence evolution natural selection sexual selection theory

Key Vocabulary