1. BIOLOGY NOTES EVOLUTION PART 1 PAGES 297-319

2. Standards:
6.1
____Explain how the scientific theory of evolution is supported by the fossil record, comparative anatomy, comparative embryology, biogeography, molecular biology, and observed evolutionary change ____ Describe the conditions required for natural selection, including: overpopulation of offspring, inherited variation, and the struggle to survive, which results in differential reproductive success ____ Describe how mutation and genetic recombination increases genetic variation ____ Explain how and why the genetic code is universal and is common to almost all organisms
6.2
6.3
6.12

3. Essential Questions: What mechanisms have allowed for 1. 2.
diversity in organisms?
1. 2.
How is the scientific theory of evolution
supported by different disciplines?

4. Evolution = the biological process of _______ by which ____________ come to differ from their __________
change
descendents
ancestors

5. A. History
1. Carolus Linnaeus (1700’s) – proposed that organisms are not _____ but do change over time from breeding experiments
species = a group of __________ so similar to one another they can reproduce and have ______ offspring
fixed
organisms
fertile

6. 2. Georges Louis Leclerc de Buffon (1700’s) – proposes that species _______ ancestors instead of arising separately
shared

7. 3. James Hutton (1795) & Charles Lyell (1833) – two geologists who discovered that the Earth was really ________, not thousands, of years old
Hutton and Lyell broke former ________ by studying rock layers and suggesting geographical formations due to weather, ________, and other natural forces occur slowly. Thus, the Earth must be ________ of years old.
millions
theories
erosion
millions

10. 4. Thomas Malthus (1798) – An economist who suggested that human population growth is _______ by resources such as food, water and space. A population that grew too large would result in a ________ for existence.
This led evolutionists to wonder if ________ also competed as animals generally have even more offspring than humans
limited
struggle
animals

12. 5. Jean Baptiste Lamarck (1809) – A scientist who proposed the theory of _________ characteristics
Lamarck believed that an organism’s ____ or disuse of a trait determined if it were passed on to _________
e.g.
acquired
use
offspring
fiddler crab claw, birds flying

14. This is an obviously ________ hypotheses because an organism’s ________ cannot affect it’s heredity
Lamarck’s hypotheses were important, however, because he is the first scientist to suggest that organisms do, in fact, _______ over time and are ultimately adapted to their ____________
incorrect
behavior
change
environment

15. 6. Alfred Wallace (1858) – A scientist whose studies in _________ confirms Darwin’s theory of _________
Malaysia
evolution

16. 5. Charles Darwin – proposed the modern scientific theory of _________ through the MECHANISM of _______ selection
Studied different fossils, collected evidence, and made numerous observations while on board the _____________ in 1831
got most of his evidence from the __________ islands
Published the ______ of Species in 1859 with his mechanism (how it happens) of evolution
evolution
natural
H.M.S. Beagle
Galapagos
Origin

19. B. Darwin’s Modern Theory of Evolution
Premise #1: Individuals differ and these differences are _________ (passed on to offspring)
At this point in time Mendel’s work was not very well known so Darwin did not know ____ variation among organisms occurred
inherited
how

20. Darwin, however, did know variation occurred among ________ species by observing and recording variation among _________ of organisms
e.g.
with Mendel’s work, we now know this variation occurs at the genetic level and we call the variations for a single trait _______
different
hundreds
finches, tortises, etc.
alleles

21. with a better understanding of genetics we now know variation occurs because of ___________ and during _______ reproduction / _________ over
mutations
sexual
crossing

24. Premise #2: Organisms _________ for limited resources.
Struggle for existence = members of the same ________ regularly compete for _____, living space, etc.
compete
species
food

25. Members of the same species compete because of ______________
overpopulation

26. Fitness = the ability of an individual to _______ and reproduce in its environment
each organism has advantages or disadvantages in the struggle for _______
adaptation = any inherited _____________ that increases an organism’s chances of ________
survive
survival
characteristic
survival

29. If the environment changes, something that may have been an _____________ could or could not be of use
e.g.
adaptation
dinosaur size

30. Premise #3: Within each species competition, there are winners and ______
Natural Selection (a.k.a.) Survival of the fittest = those organisms best ________ to their environment survive to reproduce and these organisms pass on their traits (acts on ___________)
Evolution occurs through _______ selection (also known as the MECHANISM of evolution)
losers
adapted
phenotypes
natural

31. Conclusion #1: Those species of organisms that are alive today are ____________ from a common ________ but, have been _________ or changed over time (EVOLUTION)
As natural selection occurs, species gradually become very ________ from each other
this is what Darwin termed ________ with ____________
descendent
ancestor
modified
different
descent
modification

32. C. Evidence for the Scientific Theory of Evolution 1
C. Evidence for the Scientific Theory of Evolution 1. Fossils = preserved remains or _________ of the existence of an organism e.g.
evidence
dino bones

33. This tells us that there have been a _______ of different organisms alive over millions of _____
The lower in the rock layers, the _____ the organism is believed to be
Within millions of years there are large _____ WHY? ______________
variety
years
older
gaps
decomposition

37. most fossils are found in ____________ rock
b. other types of fossils include: ______, amber preserved fossils, petrified fossils, imprints, and ______
sedimentary
casts
molds

38. c. as ____________ continues, many missing “links” have been ___________
paleontology
discovered

39. 2. Homologous Body Structures = structures that have different ________ but the same basic _________
e.g.
Similar structures indicate similar genetic codes in the _____ molecules of an organism
Remember the genetic code is _________ and millions or even billions of base pairs long in every cell
function
structure
bat wings, human hand, whale flipper
DNA
universal

40. It is unlikely that long sequences of matching base pairs exist in two ________ species unless these organisms evolved from a _________ ancestor
this can be proven using genetic ___________
different
common
sequencing

42. Why would organisms have organs they do not use?
3. Vestigial Organs = organs present within an organism that serves no useful ________
e.g.
Why would organisms have organs they do not use?
if the organs do not affect the survival of ____, then natural selection would not have eliminated these organs
this can also explain why there are ________ pieces of DNA found in almost all _____________
function
human appendix
life
unused
organisms

43. The presence, however, of vestigial organs suggests that several different _______ could have evolved from a single ________
species
ancestor

44. 4. Embryology
Many organisms look similar in structure as ________ which indicates they have a common _________
e.g.
Why do organisms eventually look extremely different from embryo to full grown individual? ________________
embryos
ancestor
rat, human, chicken
cell differentiation

46. Larva
Adult barnacle
Adult crab

47. 5. Molecular & Genetic Evidence = it has been shown that very different ________ have similar molecular and ________ mechanisms
the more related two organisms are, the more _______ their DNA will be
species
genetic
related

48. pseudogenes = sequences of _____ nucleotides that are no longer _______
having similar _____________ reflects a common _________
6. Biogeography - Geographical ____________ of common plants & animals
e.g.
7. Observed Evolutionary Change
DNA
useful
pseudogenes
ancestor
distribution
Whale bones in African desert
Spread of antibiotic resistant bacteria