Download Notes Unit 5 Part 1

BIOLOGY NOTES
EVOLUTION PART 1
PAGES 297-319
NAME:
DAY / MOD:
DATE:
Standards:
____ 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
Essential Questions:
1.
2.
I. Evolution = the biological process of ______________ by which ___________________ come to differ from
their _________________
A. History
1. Carolus Linnaeus (1700’s) – proposes 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
2. Georges Louis Leclerc de Buffon (1700’s) – proposes that species _______________ ancestors instead
of arising separately
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 are due to weather, ______________, and other natural forces that occur slowly. Thus, the
Earth must be _________________ of years old
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
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.
 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 _______________
6. Alfred Wallace (1858) – A scientist whose studies in __________________ confirms Darwin’s theory of
____________________
7. 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
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 got most of his evidence from the ____________________ islands
 Published the ___________ of Species in 1859 with his mechanism (how it happens) of evolution
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
 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 ____________
 with a better understanding of genetics we now know variation occurs because of
_________________ and during _______________ reproduction/____________ over
Premise #2: Organisms ______________ for limited resources.
 Struggle for existence = members of the same ______________ regularly compete for _________,
living space, etc.
 members of the same species compete because of ___________________
 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
__________________
 if the environment changes, something that may have been an __________________ could or could
not be of use
e.g.
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)
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 ________________________
C. Evidence for the Scientific Theory of Evolution
1. Fossils = preserved remains or _______________ of the existence of an organism
e.g.
 This tells us that there have been _______________ 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? ________________________
a. most fossils are found in _______________________ rock
b. other types of fossils include: ________, amber preserved fossils, petrified fossils, imprints, and
_________
c. as ___________________ continues, many missing “links” have been ______________________
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2. Homologous Body Structures = structures that have different _____________ but the same basic
________________
e.g.
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
__________________
 The presence, however, of vestigial organs suggests that several different ____________ could have
evolved from a single __________________
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?
____________________________
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
 pseudogenes = sequences of _______ nucleotides that are no longer _______________
 having similar ___________ reflects a common _________________
6. Biogeography - geographic ______________ of common plants and animals
e.g.
7. Observed Evolutionary Change
e.g.
STUDENT SYNTHESIS
To demonstrate knowledge of the information contained within these notes, within the space below EITHER 1. Create two higher
level test questions and answers based on the information OR 2. Write a comprehensive summary of the information
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