development of the theory of evolution Flashcards
1
Q
recap
A
- universe started 13.7 bya
- earth is 4.6 byo
- crust built in layers
- dating fossils
- at least 5 mass extinctions
- fossil studying : ancient forms; life-forms and changes; support of species changing
- South Africa rich in fossils
2
Q
evolution
A
- gradual change or development of something
3
Q
biological evolution
A
- change in the gene pool of a population
- mutation
- natural selection
- genetic drift
- descent modification
4
Q
why is it so important that we know about biological evolution?
A
- unifying concept for understanding biology
- supports and explains aspects of everyday life
- challenges introspection
5
Q
How did life originate?
A
- single origin of life
- all life shares same genetic code
- similar enzymes
6
Q
before 1700
A
- species were unrelated
- remained unchanged
- earth was young
7
Q
1700 - 1800
A
- Erasmus Darwin (Charle’s grandfather)
- Jean-Baptiste Lamarck
- species had changed gradually over time
- earth was millions of years old
8
Q
Erasmus Darwin (1731-1802)
A
- country doctor
- philosopher
- earth descended from a common ancestor
- species must have changed / evolved over time
- transformation
9
Q
Jean-Baptiste Lamarck (1774-1829)
A
- naturalist
- Philosophie Zoologique
- living species are different to fossil types (evolution)
- domestication and selective breeding (animal and plant changes)
- cross-breeding led to new characteristics
10
Q
how did lamarck suggest that species changed?
A
- natural phenomenon
- in order to survive in new environments
- acquired changes were passed to offspring
- use of body parts would increase in size and efficiency as used more
- the less used and efficient, would get smaller and disappear
- phenotypic changes acquired by parents were passed to offspring
- inheritance of acquired characteristics
11
Q
lamarckism
A
- long neck giraffes
- evolved from short neck giraffes for higher leaf acquiring
12
Q
was lamarck’s mechanism for evolution correct?
A
- environment can produce phenotypic changes
- correct, but not for evolutionary changes
- species have common ancestors
- evolution occured as species adapted to their environment
13
Q
early 1800 - 1900
A
- charles darwin
- alfred russel wallace
14
Q
charles darwin (1809 - 1882)
A
- immense diversity among organisms
- variation of individuals
- often puzzling distribution of different species
- earth is extremely old
- great geological change
- isolation leads species to change
- modification with descent (evolutionary change)
- natural selection : how evolution takes place
15
Q
how did Darwin explain descent with modification?
A
- descended from common ancestor
- adapted to new local conditions after spreading
- diversification by branching
- some species died out
