1. What is Evolution? AND Evolution explains BOTH
changes in living organisms and their genes over time
We KNOW based on evidence and observations
explains how modern organisms have descended from ancient organisms
Evolution explains BOTH
unity of life - similarities between all living things
AND
diversity of life - wide variety of different creatures on Earth

2. UNITY: All creatures have common characteristics
How did we get GRSNERRT?
DNA – codes for _______________
Proteins are made of _______________
Amino acids are coded for by ________
The 3 bases are called _________
Codons are translated using the “Universal” code - works for ALL living things!!!!!!!
Determines ADAPTATIONS

3. determines Adaptations
DIVERSITY - variation BOTH within a population and the wide variety of living things (remember classification – 6 Kingdoms)
Sexual Reproduction
Two parents contributing genes
In Meiosis – crossing over
New combinations of parents genes
Mutation, mutation, mutation
sometimes beneficial -
determines Adaptations

4. Adaptations
Traits that help an individual survive – may not know it’s beneficial
Physical – color, structure
Behavioral – instincts, courtship
Biochemical/physiological – enzymes, sweating, internal characteristics
Born with adaptations – are NOT chosen
GENES determine adaptations (remember genotype determines phenotype)

5. Adaptations NO organisms BECOME adapted
They are either born adapted or they are not.

6. What determines survival?
Natural Selection
traits that help individuals survive
survive predators
survive disease
compete for food
compete for territory
traits that help individuals reproduce
attracting a mate
compete for nesting sites
successfully raise young
Adaptations
Survival & Reproduction of the Fittest

7. Earlier ideas on Evolution
LaMarck
evolution by acquired traits
creatures developed traits during their lifetime
give those traits to their offspring
example
in reaching higher leaves giraffes stretch their necks & give the acquired longer neck to offspring
not accepted as valid

8. Charles Darwin Proposed a way how evolution works 1809-1882
British naturalist
Voyage of the HMS Beagle
Stopped in the Galapagos Islands
Proposed a way how evolution works
natural selection
What did Darwin say?
What evidence supports Evolution by Natural Selection?
What impact did Evolution have on biology?

9. Voyage of the HMS Beagle
Stopped in Galapagos Islands
500 miles off coast of Ecuador
The origin of the fauna of the Galapagos, 900 km west of the South American coast, especially puzzled Darwin.
On further study after his voyage, Darwin noted that while most of the animal species on the Galapagos lived nowhere else, they resembled species living on the South American mainland.
It seemed that the islands had been colonized by plants and animals from the mainland that had then diversified on the different islands

10. Darwin found: many unique species
Different shells on tortoises on different islands
Darwin asked:
Is there a relationship between the environment & what an animal looks like?

11. The finches cinched it! different beaks are inherited variations
serve as adaptations that help birds compete for food
these birds survive & reproduce
pass on the genes for those more fit beaks
over time nature selected for different species with different beaks
Darwin found:
The differences between species of finches were associated with the different food they ate.
Finch?
Sparrow?
Woodpecker?
Warbler?
Darwin said:
Ahaaaa! A flock of South American finches were stranded on the Galapagos…
Large ground finch
Big seed eater
Small ground finch
Small seed eater
Insect eater
Warbler finch
Leaf & bud eater
Tree finch

12. Darwin’s finches Darwin’s conclusions variations in beaks
differences in beaks in the original flock
adaptations to foods available on islands
natural selection for most fit
over many generations, the finches were selected for specific beaks & behaviors
offspring inherit successful traits
accumulation of winning traits: both beaks & behaviors
separate into different species(speciation)

13. Modern Natural Selection
Overproduction – not all offspring will survive
Variation – (3 sources) differences in adaptations (3 types)
Competition – “struggle for survival”
Environment (nature) determines which adaptations are the “fittest”
Best adapted survive and reproduce – pass on the “fit” genes to next generation
The gene pool changes = EVOLUTION – Not the individual

14. 3 Types of Selection 1. Stabilizing 2. Directional 3. Disruptive
Niche – organism’s role or “job” in an ecosystem
ex: predator/prey, habitat, relationships with other organisms, when it is “active”
ONLY ONE (1) species may occupy a niche at a time - total overlap results in “extinction” of the less fit from that ecosystem

15. Stabilizing Selection
Favors the average – decreases variation
Extremes are selected against
Example – spiders - too big: can be easily seen by predators; too small: can’t compete for web building sites

16. Directional Selection
Favors one extreme or the other
Example – finch beaks – small or large food; also peppered moths

17. Witness to Evolution Peppered Moth 2 types: dark vs. light light

18. Peppered moth Why did the population change?
early 1800s = pre-industrial England
low pollution
lichen on trees = light colored bark
late 1800s = industrial
factories = soot coated trees
killed lichen = dark colored bark
mid 1900s = pollution controls
clean air laws
return of lichen = light colored bark

19. Disruptive Selection Favors BOTH extremes at the same time
Leads to speciation – two separate species forming to fill different niches
ONLY one species can occupy a given niche in an ecosystem (increased competition leads to narrower niches)

20. Relationship between species (beaks) & food

21. Other Evidence supporting evolution
1. Fossil record
shows change over time
2. Anatomical record
comparing body structures
homology & vestigial structures
embryology & development
3. Molecular record
comparing protein & DNA sequences
4. Artificial selection
human caused evolution

22. → supports the idea of a common ancestor Types:
1. Fossil record
Layers of rock contain fossils
new layers cover older ones
creates a record over time
fossils show a series of organisms have lived on Earth
Link between birds and reptiles
Link between land and sea animals
→ supports the idea of a common ancestor
Types:

23. What do we know?
Creatures have changed over time
Fossil Record

24. 2. Homologous structures
Structures that come from the same origin
homo- = same
-logous = information
Forelimbs of human, cats, whales, & bats
same structure
on the inside
same development in embryo
different functions
on the outside
evidence of common ancestor

25. 2. Anatomical strucures The same bones under the skin
limbs that perform different functions are built from the same bones

26. Vestigial organs Structures on modern animals that have no function
remains of structures that were functional in ancestors
evidence of change over time
some snakes & whales have pelvis bones & leg bones of walking ancestors
eyes on blind cave fish
human tail bone

27. Human vestigial organs
2. t________ b_______
3. w_______ t_________
No longer have a function or are necessary – may have had a function at one time

28. Comparative embryology
Development of embryo tells an evolutionary story
similar structures during development
all vertebrate embryos have a “gill pouch” at one stage of development

31. Video – Evolution in Action – Silver Foxes
4. Artificial selection
We know natural selection can change a population?
we can recreate a similar process
“evolution by human selection”
“descendants”
of the wolf
Humans create the change over time
Video – Evolution in Action – Silver Foxes

32. But don’t be fooled by these…
Analogous structures
look similar
on the outside
same function
different structure & development
on the inside
different origin
no evolutionary relationship
Solving a similar problem with a similar solution

33. Convergent evolution led to mimicry
Why do these pairs look so similar?
Monarch male
poisonous
Viceroy male
edible
Which is the moth vs. the bee?
Which is the fly vs. the bee?
fly
bee
moth
bee

34. For examples of Natural Selection –
1. ID variation in the population
2. ID type of variation (adaptation)
3. ID source of variation
4. ID selecting agent (e___________)
5. individuals with advantageous variations – survive;
6. THEN they get to reproduce
7. State which variation increases and which variation decreases

35. Artificial Selection gone bad!
Unexpected and often dangerous consequences of artificial selection
Antibiotic resistance
Bacteria
Pesticide
(and herbicide)
resistance
Insects
And
Weeds

37. Insecticide resistance
Spray the field, but…
insecticide didn’t kill all individuals
variation
Insecticide did NOT cause the resistance – it’s the selecting agent
resistant survivors reproduce
resistance is inherited
insecticide becomes less & less effective
The evolution of resistance to insecticides in hundreds of insect species is a classic example of natural selection in action.
The results of application of new insecticide are typically encouraging, killing 99% of the insects.
However, the effectiveness of the insecticide becomes less effective in subsequent applications. The few survivors from the early applications of the insecticide are those insects with genes that enable them to resist the chemical attack. Only these resistant individuals reproduce, passing on their resistance to their offspring. In each generation the % of insecticide-resistant individuals increases.

39. Antibiotic Resistance

40. REVIEW - Evidence of Evolution
1. Fossils
2. Comparative Anatomy
h______________ structures
v____________
e________________
3. Comparative Biochemistry
________ and p___________
4. Artificial Selection
b________________
i____________ and a_______________

41. Time Frame for Evolution
Punctuated Equilibrium
Periods of stability followed by periods of rapid change (speciation) OR extinction due to rapidly changing environment
Adaptations must already exist in population

42. Time Frame for Evolution
Gradualism
Slow, continual change due to a more stable environment

43. Recent or now
Species
Alive today
Extinct
Period of
stability
Change in environment
Common Ancestor
Oldest

44. Evolutionary Time Frame
Evolution is caused by changes in the environment
Natural – caused by nature
Artificial – caused by humans
Ex: pesticide and antibiotics
Evolution is faster with organisms with short life cycles AND lots of offspring
Examples – insects and bacteria

45. Natural Selection - Summary
Adaptations – 3 types: p_________, b________, ph________________
Born with – determined by genes
Variation – 3 sources: s____, c_______ o____, m________; NOT e___________
Competition – struggle for resources (food, shelter, mates) to s_________________
“Fittest” or best adapted are selected for by s___________ a_________ in the e_______________
If “fit” – reproduce and pass on g______
Gene pool evolves (NOT the individual) from selection – 3 types: s___________, d_____________, d____________

46. Summary – One more time WAY too many offspring are produced
1. Overproduction –
WAY too many offspring are produced
2. Variation –
3 sources -
Adaptations – DO NOT get to Choose
3 types -

47. Summary - Continued That is EVOLUTION!!!!!
3. Selection – selecting agent
Natural – environment
Artificial – human
→ “fittest” survive
4. Reproduction
Pass on “fit” genes
→Over time “fit” genes increase
→ gene pool of a population changes
That is EVOLUTION!!!!!

48. Study Guide Vocab, vocab, vocab!!!!!!!
Evolution – unity and diversity – p.___
Darwin – Galapagos – p.____
Natural Selection – p. ____
Overproduction
Variation in adaptations – 3 types, 3 sources
Competition
Survival of fittest – 3 types of selection – p._
Evidence of Evolution – 4 pieces – p. ____
Time Frame for Evolution – 3 theories – p. ____