Transcript Principles of Evolution - Grafton School District

Principles of
Evolution
Chapters: 12, 13, 14
begin?
How did life
The Bubble Model (1986)
by Lerman
 Chemical reactions
of the primordial
soup took place
inside bubbles of fat
molecules.
 See page 255 in
book
Primordial Soup (A.I.
Oparin)
 Early Earth atmosphere
(N, Methane, ammonia)
 Energy from sun,
volcanoes, lightning
 Chemical reactions
created amino acids
 Rain washed these into
the ocean
 Created the primordial
soup.
A Brief History of Life
 animation
Early Organisms
 Prokaryotes are
oldest organisms
(3.5 billion years old)
 Cyanobacteria –
photosynthetic
bacteria
 Impact on
atmosphere:
Oxygen!!!!
Groups of bacteria
 Eubacteria- “true
bacteria”, ex. Ecoli
 Archaebacteria –
ancient bacteria,
Then came the eukaryotes
 Appeared 1.5 billion
years ago
Life moved onto land!!!
The Theory of
Evolution
Chapter 13
13-1 Where did the theory of natural
selection come from?
 Pre Darwin:
 (1809) Jean Baptiste
de Lamark
 Variation hypothesis
– evolution occurs
through acquired
characteristics (body
changes over time)
 Example: giraffe neck
length
Larmark: Aquired
Characteristics
Evolution by Natural
Selection
 Charles Darwin
(1859)
 Journey of the
H.M.S. Beagle –
recorded all the
plants and animals
on journey
Darwin’s Observations
 Observed gradual
change – found fossils
that were similar, but not
identical, to the current
day animal
 On Galapagos island he
observed finches that
resembled those in
South America
Darwin’s finches: notice the
beaks
I. Natural Selection- survival
of the fittest (Darwin)
1. Variations exist within populations
Theory of Natural
Selection
2. Some variations (mutations) are more
advantageous for survival and
reproduction than others
Theory of Natural
Selection
3. “fit”organisms
survive and
reproduce – genes
are passed to
offspring
 Isolation- leads to a new species, two
population of same species can not
breed
 Extinction- leads to species replacement
Adaptations
 Changing of a
species that results
in its being better
suited to its
environment
(choosen by natural
selection)
 Mutations
Peppered Moth Example
Structural Adaptations
 Mimicry
 Camouflage
 Warning coloration
Structural Adaptation: 1.
Mimicry
Example: Viseroy and Monarch Butterflies
Viceroy
Monarch
2. Camouflage
 adaptations that allows an organism to
"blend" into it's environment
 Examples:
More examples of Camo.:
Sea Dragon
Structural Adaptation:
Warning: Standing out
Poison Arrow Frog
Warning and Mimicry
A regal ring-necked snake displaying its
aposematic coloration
Physiological Adaptation
Changes in metabolic processes:
venom, warm vs. cold blooded
More physiological
adaptations:
Behavioral Adaptations:
examples
Jaguar – hunting methods – one bite – occipital crunchers
Evidence of
Evolution
Fossil Evidence
 Missing links
between groups of
organisms.
 Compare fossils with
current day species
Structures and Evolution
 Homologous
structures – agreeing
 Similar structures
and derived from the
same body part.
 Ex. Bone structure
Vestigial structures
 Remnant of another
structure
 No function, reduced
in size
 Ex. Appendix,
tailbones,wisdom
teeth in humans,
hipbones in whales,
Some Alleged Vestigial Organs in Man
• Tonsils
• Coccyx (tail bone)
• Appendix
• Little toe
• Wisdom teeth
• Nipples on males
• Nodes on ears "Darwin's points"
• Ear muscles for wiggling
• Body hair
Darwin’s Points
Human Appendix
Human Tonsils
Analogous Structures
:opposite
 Similar in function,
but different
structures
 Wing of butterfly vs
wing of a bat
III. Embryo Development
 Theory: aquatic, gill breathing vertebrates
came before land, air breathers
DNA Evidence
(biochemical)
 DNA sequence
studies are more
reliable than fossil
studies.
Human Evolution
Chapter 14
Evolution of Primates
 Includes Monkeys,
apes, humans
 Evolved 40 million
years ago
 3-D vision
 Flexible
shoulders/rotating
forelimbs
Primate Characteristics
cont.
 Opposable thumb
 Complex brains
- Hominid
• - humanlike, bipedal primate
Ardipithecus ramidus
 4.4 mya
 Most primitive
hominid
 Discovered 1992
Australopithecus
 Australopithecus
anamnesis
 - oldest upright
primate
 - 4.2 – 3.9 million
years old
Australopithecus
afarensis
 “Lucy” –
 3.5 – 2.9 million
years ago
 Teeth and pelvis
resemble humans
Homo habilus
 - handy human
 - larger brain
 - stone tools
 - 1.5 to 2 million
years old
Homo erectus
 upright human
 - built fires
 - well made stone
tools
 - 1.5 million years old
HOMO ERECTUS
Modern Humans - Homo sapiens
 wise human
 - 125,000 years ago,
African origins
 - Neanderthals- heavy
bodies

- 5 feet tall

- good hunters

- lived in caves

- buried dead

- did not make it
Cro-Magnon
 slighter build and taller
 - 35,000 years old
 - direct ancestors to
humans
 - out competed
Neanderthals
 - caves
 - elaborate tools
 - artists
Cro-Magnon