1. EVOLUTION & SPECIATION

2. VOCABULARY REVIEW EVOLUTION – CHANGE OVER TIME
NATURAL SELECTION - INDIVIDUALS BETTER ADAPTED TO THE ENVIRONMENT ARE ABLE TO SURVIVE & REPRODUCE.
A.K.A. “SURVIVAL OF THE FITTEST”

3. NEW VOCABULARY
POPULATION – GROUP OF INDIVIDUALS OF SAME SPECIES THAT INTERBREED
GENE POOL – COMMON GROUP OF ALL GENES PRESENT IN A POPULATION

4. Variation in Populations
2 processes can
lead to this:
Mutations -
change in DNA
sequence
Gene Shuffling –
from sexual
reproduction

5. Nonrandom mating: inbreeding and assortive mating (both shift frequencies of different genotypes)

6. Natural Selection: differential success in reproduction; only form of microevolution that adapts a population to its environment

7. Evolution of Populations
Occurs when there is a change in the types of genes in a gene pool

13. Conditions needed for Genetic Equilibrium

14. SPECIATION THE FORMATION OF NEW SPECIES
AS NEW SPECIES EVOVLVE, POPULATIONS BECOME REPRODUCTIVELY ISOLATED
REPRODUCTIVE ISOLATION – MEMEBERS OF 2 POPULATIONS CANNOT INTERBREED & PRODUCE FERTILE OFFSPRING.

15. 3 ISOLATING MECHANISMS……..
BEHAVIORAL ISOLATION- CAPABLE OF BREEDING BUT HAVE DIFFERENCES IN COURTSHIP RITUALS (EX. MEADOWLARKS)
GEOGRAPHICAL ISOLATION – SEPARATED BY GEOGRAPHIC BARRIERS LIKE RIVERS, MOUNTAINS, OR BODIES OF WATER (EX. SQUIRREL)
TEMPORAL ISOLATION – 2 OR MORE SPECIES REPRODUCE AT DIFFERENT TIMES.

16. Tigon
Result of male tiger and female lion mating in captivity. Offspring are infertile.
Separated both geographically and ecologically.

17. Liger
Result of male lion and female tiger mating in captivity. Offspring are infertile.

21. SPECIATION IN DARWIN’S FINCHES
SPECIAITON IN THE GALAPAGOS FINCHES OCCURRED BY:
- FOUNDING OF A NEW POPULATION,
- GEOGRAPHIC ISOLATION which led to -- REPRODUCTIVE ISOLATION and
CHANGES IN THE NEW POPULATION’S GENE POOL due to COMPETITION.

24. Big Question!!! How did life arise on the big blue planet??
Scientists attempt to answer this question scientifically.

25. Big Bang Theory
A cosmic explosion that hurled matter and in all directions created the universe billion years ago
Evidence
it explains why distant galaxies are traveling away from us at great speeds
Cosmic radiation from the explosion can be observed
The Big Bang theory probably will never be proven; consequentially, leaving a number of tough, unanswered questions.

26. What was early earth like?
Earth was Hot!!
Little or no oxygen
Gasses in atmosphere:
Hydrogen cyanide (poison to you!)
Hydrogen sulfide
Carbon dioxide
Carbon monoxide
Nitrogen
water

27. So how did the earth get oxygen?
Some of that oxygen was generated by photosynthetic cyanobacteria
Some came from the chemical separation of water molecules into oxygen and hydrogen.

28. Others evolved ways of using oxygen for respiration
Oxygen drove some life forms to extinction
Others evolved ways of using oxygen for respiration

29. How did life begin? Miller and Urey’s Experiment
Passed sparks through a mixture of hydrogen methane ammonia and water
This produced amino acids – the building blocks of life

30. Miller’s experiment suggests that lightning could have produced amino acids