Transcript HISTORY OF EVOLUTIONARY THOUGHTNEW

HISTORY OF
EVOLUTIONARY
THOUGHT
From Paganism
to Darwin and
Beyond
http://www.pbs.org/wgbh/evolution/educators/lessons/lesson6/act1notes.html
WHAT IS EVOLUTION?
► The
change of species over a period of time
WHAT IS YOUR OPINION?
Please write down the answers to the following
questions in your notes.
►
Cheetahs can run faster than 60 miles/hour when
chasing prey. How would a biologist explain how this
ability evolved in cheetahs assuming their ancestors
on average ran 20 miles/hr?
►
Cave salamanders are blind (their eyes are nonfunctional). How could a biologist explain how this
inability evolved from sighted ancestors?
PRE-DARWIN IDEAS
►Earth
is young
►Earth
is not changing
HISTORY: In the beginning…
Plato and Aristotle (mid 300 B.C.)
► Scale of Nature
EVIDENCE FROM GEOLOGY
James Hutton
► He proposed the theory of uniformitarianism
► Earth was formed entirely by slow-moving
processes, such as erosion and sedimentation,
and that these slow forces continue to shape
the landscape.
Charles Lyell
► 1830 wrote Principles of Geology that Darwin
read on his journey supporting Hutton’s work
JUDEO CHRISTIAN CULTURE
Exploring God’s work
► Carlos Linnaeus (1700s):
Taxonomy
► George
Cuvier (late 1700s):
- Paleontology: Found that fossils were dissimilar
to modern life
- Species can become extinct
- Species can change over time
► Giant
sloth did not
resemble modern
day sloth
Erasmus Darwin
► Grandpa!
► Termed
evolution
► Life developed from a single
sources
► Humans close to primates
(how dare he!)
O.K. SPECIES EVOLVE BUT WHAT
MAKES THEM EVOLVE?
MECHANISMS BEHIND EVOLUTION
Jean Baptiste Pierre Antoine de Monet,
Chevealier de Lamarck…a.k.a. Lamarck!
► Published in 1809 when baby Darwin was
born 
► Looked at fossil record and role of
environment
► Idea
► Idea
#1: use and disuse
#2: inheritance of acquired
characteristics
LAMARCK’S IDEA
Charles Darwin (1809-1882)
► Beagle
voyage
around the world
► Looked at living
organisms and
fossil record
VOYAGE ON THE BEAGLE
PATTERNS IN DIVERSITY
1. Species vary Globally
Rheas in South America
Emu in Australia
Ostrich in Africa
Darwin questioned why are marsupials
only found in Australia even though
Europe had a similar environment.
Unique South American Character
►A
South American
tropical lizard more
similar to a S.A.
desert lizard than
another lizard
elsewhere
2. Species Vary Locally
► What
does the
difference in
structure
between the
two tortoises
tell you about
the island they
occupy?
Galapagos Tortoises
3. Species vary over time
► Ancestor
of
armadillo
was much
bigger
►Darwin
also observed on his
journey the geological process
Hutton and Lyell also observed
►He witnessed earthquakes,
changing landscapes
►He found marine fossils high up
in the mountains of the Andes
in Chile
Working towards a theory of
Natural Selection
► Malthus’
work:
population size can
increases
exponentially but it
remains stable over
time…why?
3 Points To Darwin’s Theory
►
1. There is a struggle
for existence
2. Role of the Environment: Natural
Selection
► There
is variation in a population
The environment plays a
role in
► keeping populations in
check
► Natural selection is
the process of
selecting for a
variation that is best
suited to its
environment
► “Survival of The Fittest”:
those that can survive
and reproduce the most
viable offspring are the
most fit
3. Descent with Modification
Alfred Wallace (1823-1913)
►I
have this theory about natural selection charlsey
boy, what do you think?
Darwin’s Origin of Species
► Decent with modification (evolution)
► Natural Selection
► Decent
of Man was also then published
Lamarck vs. Darwin
► Did
your ideas reflect Darwin or Lamarck’s
► What does modern day genetics support?
Evolution of Hummingbirds
http://www.youtube.com/watch?v=uHyjGQJCAMU
► http://www.pbs.org/wgbh/evolution/library/11/2/e
_s_4.html