ANTA01 – week 2 “EVOLUTION” G.Kim
Evolution is ‘descent with modification’
-History of evolution
CONCEPTS ON EVOLUTION AND HUMAN ORIGINS
• WHAT IS EVOLUTION & HOW DOES IT WORK?
*Evolution: 1. Natural selection
2. Survival of the fittest
3. Adaptation to the environment
4. Traits already present (variation)
5. Sexual selection
*EVOLUTION works based on an entire population (species) not
Species: group of organisms that breed together and produce viable and fertile
- May be quite similar in appearance (deer) or quite variable (dogs)
- May all live in one part of the world (polar bears) or in many parts of the
world (right whales)
- Share behavioral traits in relation to social groups, food preferences,
reproductive strategies, etc (depending on the region and their lifestyles)
- Distinguish between members of own species and others.
Darwin –“The Origin of Species” in 1859
Very religious & studied the finches (*pigeons) & earthworms
HISTORY OF ORIGINS
- Origin of the Earth & therefore humans based on his interpretation of the
! Genesis: humans were made by an extravagant technology
! James Ussher (1581-1656): He came up with the age of the Earth:
6000yrs old today. October 23rd 4004BC at 9:00am.
- George Cuvier: * if only 6000 yrs old, then global and violent catastrophes
to explain canyons, mountains...? Completely convinced that the earth was
6000 yrs old.
- Reverend Burnet (1681AD) slow erosion? Water wind and ice.
- Buffon (1749AD) “to learn about the earth, study the earth” – processes are
known, natural and observable.
- Hutton (1788AD) slow working, uniform & natural processes= hundreds of
thousands or yrs
- Lyelle (1873AD) 100,000 yrs “the present is the key to the past”
ANTA01 – week 2 “EVOLUTION” G.Kim
- Reverend Chalmer – Ussher was wrong, not the Bible.
At the same time...
CARLOUS LINNEUS (1758)
- Categorizing the worlds plans & animals
- 7 layers of taxon levels: Kingdom, Phylum, Class, Order, Family, Genus,
- Binomial system
- Homo sapiens (wise men)
Life on Earth had CHANGED!
" Conclusion of the Enlightenment period
" Extinct animals
" Strata & Stratigraphy (we should be able to UNFOLD our entire history! with
the geographical help we can get from the nature!)
" 1800’s the question changed to -> ‘HOW did the Earth/Species CHANGE?’
Adding to the fire....
" Colonization: identified new peoples not mentioned in the Bible
(Groups of different regional people- not expected to be humans)
" Archaeology: -stone tools/ ‘thunderstones’/ or pre-metal Stone Ages???
LAMARCK –First Mechanism
1. Adaptation to the environment
2. Progression towards perfection
3. Inheritance of acquired characteristics
Ex) giraffes: wouldn’t it be better for giraffes to have longer neck to eat plants
in higher location? That’s why as time passed by, giraffes grew taller because
they saw the advantage in being tall -> why humans continue to REACH
THEIR IDEAL FORM
DARWIN & WALLACE Mechanism of Natural Selection
" Natural Selection- variation already exists between individuals of the same
species, allows for adaptation to changes in the environment
" Survival of the Fittest & Sexual Selection- Those individuals that are by
chances best adapted to an environment will have higher reproductive
" Increase the frequency of that trait within the species/ population
" Variation is RANDOM and there is NO DIRECTION
Case study: Grant & Grant 2002
Finches – female finches chose male finches with bigger beaks because they
could supply more foods to their offsprings. (Bigger beaks = more access to food)