Transcript Chapter 4 Evolution: History and evidence

CHAPTER THREE
EVOLUTION
HISTORY AND EVIDENCE
Pre~Darwinian Theories of
Change
The idea of evolution did not
originate with Charles Darwin.
Darwin’s Early Years and His
Journey
At the age of 16 he entered medical
school in Edinburgh, Scotland
During his stay at Cambridge, Darwin
developed a keen interest in
collecting beetles and made
valuables contribution to beetle
taxonomy
Early Development of Darwin’s
Ideas of Evolution
Darwin’s theory of evolution by
natural selection was long,
painstaking process.
Darwin had to become convinced
that change occurs overt time
During his voyage suggested that
change occur, he realized the 6000
years could not account for the
diversity of modern species if they
arose through gradual change
Geology
Lyell developed the ideas of another
geologist, James Hutton, into the
theory of uniformitarianism
His theory was based on the idea
that the forces of wind, rain, rivers,
volcanoes, and geological uplift
shape the earth today, just as they
have in the past.
Fossil Evidence
Once the HMS Beagle reached South
America, Darwin spent time digging
in the dry riverbeds of the pampas
(grassy plains) of Argentina
He found the fossil remains of an
extinct hippopotamus like animal,
now called Toxodon, and fossil of a
horselike animal, Thoantherium
Natural Selection
Natural Selection
Charles Darwin had no knowledge of
modern genetic concepts and
therefore, had no knowledge of the
genetics principles that are the the
basic of evolutionary theory as its
exists today
Adaptation
Occurs when a change in a
phenotype increases an animals
chance of successful reproduction.
Adaptation sometimes used of the
term is probably less confusing ran
when it is used to describe the result
of the process of change
Alfred Russell Wallace
He was an explorer of the Amazon
valley and the led a zoological
expedition to the Malay archipelago
Wallace like Darwin was impress with
the evolution change and had the
writing of Thomas Malthus o human
populations
and Evidence of
Macroevoluntionary Change
A change in the frequency of alles in
population over time is called
microevolution
The processes that result in
microevolution are discussed..
Biogeography
Is the study of the geographic
distribution of plants and animals.
They studied show that life forms in
different parts of the world have
distinctive evoluntionary histories
Paleontology
Which is the study of the fossil
record provides some of the most
direct evidence for evolution
Analogy and Homology
The evolution of superficially similar
structures in unrelated organism is
called convergent evolution
Structure and processes in two kind
of organisms that are derived from
common ancestry are said to be
homologous
Development Patterns
Evidence of evolution also comes
from observing the development
pattern of organism
Phylogeny and Common
Descent
Phylogeny refers to the evolutionary
relationship among species