chapter 16-evolution (6) - science-b

download report

Transcript chapter 16-evolution (6) - science-b

MAKE-UP
SPECIES VARY LOCALLY
Darwin noticed that difference, yet related, animal
species often occupied different habitats within a
local area.
Good example for this is the Hood island vs.
Isabella island tortoise (galapagos islands)
SPECIES VARY OVER TIME

Darwin noticed that some fossils of extinct
animals were similar to living species.
APPLYING THE BIG IDEA

You have learned that both Biotic and Abiotic
factors affect ecosystems. Give some examples of
each, and explain how Biotic and Abiotic factors
could have affected the tortoises that Darwin
observed on the Galapagos Islands.
16.2 IDEAS THAT SHAPED DARWIN’S
THINKING
Key Questions
1. what did Hutton and Lyell conclude about
Earth’s History
2. How did Lamark propose that species evolve
3. What was Malthus’s view of population
growth?
4. How is inherited variation used in artificial
selection
Vocab:
1. Artificial selection
AN ANCIENT CHANGING EARTH
James Hutton (1726-1797)





Scottish farmer/naturalist
History of the Earth can be determined by understanding
present erosion and sedimentation
Founder of Modern Geology
Thought the earth was much older than the accepted 6,000yrs
“Theory of Uniformitarianism”: This was the belief that
geological forces at work in the present day—barely noticeable
to the human eye, yet immense in their impact—are the same
as those that operated in the past.
Charles Lyell (1797-1875)



The laws of nature are constant
Erosion/mountains/volcanoes…etc
Theory of Uniformitarianism
Summary: This all takes time!!! In order for all this to
have happened…the earth is pretty darn old!!!!
TIME……
“EVOLUTION”
Jean-Baptiste Lamarck (1744-1829)




All organisms have an inborn urge to become more complex
Change comes from using them in new ways
Changes during its life would be passed to its offsrping
“acquired characteristics”
Problems with Lamarck’s Theory:


No internal drive to better itself
Acquired traits are not passed to offspring
***Significance: He was the 1st to try to explain
evolution using the natural process
POPULATION
Robert Malthus 1766-1834
“If human population grew unchecked, there
wouldn’t be enough living space and food for
everyone”
Significance to Darwin?
1. This could apply more to other organisms
2. Why hasn’t life run out of space?
a. Why do so many die?
b. Why do so many live?
What does this support?
ARTIFICIAL AND NATURAL SELECTION
Artificial selection: nature provides the
variations, and humans select those they find
useful.
 How have we practiced “selection”


How could we?
REVIEW
What were Hutton's and Lyell’s ideas about the
age of the Earth and the processes that shaped
the planet?
 How would Hutton and Lyell explain the
formation of the grand canyon?
 What is an acquired Characteristic? What role
did Lamarck think acquired Characteristics
played in evolution?
 What parts of Lamarck’s hypothesis have been
proven wrong? What did he get right?
 According to Malthus, what factors limit human
population growth?
 How did Malthus influence Darwin

16.3 DARWIN'S CASE
Key Questions:
1. Under what conditions does natural condition
occur?
2. What does Darwin’s mechanism for evolution
suggest about living and extinct species.
Vocab:
1. Adaptation
2. Fitness
3. Natural Selection
16.3

Adaptation:


Fitness


Any heritable characteristic that increases an
organisms ability to survive and reproduce in its
environment
How well an organism can survive and reproduce in
its environment
Natural selection

Process by which organisms with variations most
suited to their local environment survive and leave
more offspring.
16.4 EVIDENCE OF EVOLUTION

Key questions
How does the distribution of species support evolution?
 How do fossils support evolution?
 How do Homologous structures and embryology support
evolution?
 What evidence of evolution comes from molecular biology?
 What does the Galapagos finches show about natural
selection
Vocab:





Biogeography
Homologous structure
Analogous structure
Vestigial structure