Category: Curriculum Map

Darwin & Natural Selection

 


Charles Robert Darwin		 Darwin and Evolution

All Materials © Cmassengale

 

History of Evolution:

  • Plato & Aristotle believed species were fixed & could be arranged according to their complexity
  • In the mid eighteenth century, Carolus Linnaeus developed a system of classification that called binomial nomenclature
  • George Cuvier, in the eighteenth century, explained changes in the fossil record by proposing that a whole series of catastrophes (extinctions) and re-populations from other regions had occurred giving the appearance of change over time
  • Prior to Darwin, it was thought that the world was young & species did not change
  • Lamarck (1744-1829) was first to state that descent with modification occurs and that organisms become adapted to their environments
  • Inheritance of acquired characteristics was the Lamarckian belief that organisms become adapted to their environment during their lifetime and pass on these adaptations to their offspring
  • Lamarck believed that the long necks of giraffes evolved as generations of giraffes reached for ever higher leaves; known as the Law of Use & Disuse

Giraffe neck extension

  • Because it is supported by so many lines of evidence, evolution is no longer considered a hypothesis
  • Evolution is one of the great unifying theories of biology

Darwin’s Background & Voyage:

  • His nature was too sensitive to become a doctor like his father so he studied divinity
  • He attended biology and geology lectures and was tutored by the Reverend John Henslow who arranged his trip on the HMS Beagle
  • In 1831, at the age of 22, Charles Darwin accepted a naturalist position aboard the ship HMS Beagle & began a five-year voyage around the world

Map showing Darwin's voyage on the Beagle

  • He read Principles of Geology by Charles Lyell that stated that the observed massive geological changes were caused by slow, continuous processes (erosion, uplifting…)
  • Darwin carried this book with him on his voyage as he witnessed Argentina coast earthquakes raising the earth several feet, & marine shells occurring far inland and at great heights in the Andes
  • Darwin’s many observations led him to the idea that species slowly change over time
  • Darwin’s comparison of the animals of South America and the Galapagos Islands caused him to conclude that adaptation to the environment can cause diversification, including origin of new species
    Examples: Patagonian hares replaced rabbits in the South American grasslands

The Galapagos Islands:

  • Volcanic islands off the South American coast
  • Island species varied from the mainland species, and from island-to-island
  • Each island had either long or short necked tortoises depending on the island’s vegetation

  • Finches on the Galapagos Islands resembled a mainland finch, but there were more types
  • Bill shapes are adaptations to different means of gathering food. Diversity of bill shape in the Hawaiian honey creeper
  • Galapagos finch species varied by nesting site, beak size, and eating habits


Darwin’s Theory of Evolution:

  • An adaptation is a trait that helps an organism be more suited to its environment
  • Darwin decided adaptations develop over time
  • Natural selection was proposed by both Alfred Russell Wallace and Darwin as a driving mechanism of evolution
  • Darwin and Wallace both read an essay by Thomas Malthus that proposed that human populations outgrow resources so there is a constant struggle for existence

mathusianpopulation.gif (10181 bytes)

  • Fitness is a measure of an organism’s reproductive success
  • Organisms most fit to reproduce are selected by environment which results in adaptation of the population
  • Natural selection is also called “survival of the fittest”
  • Conditions for natural selection include:
    a. Variations exist among members of a population
    b. Many more individuals are produced each generation than will survive
    c. Some individuals are better adapted so they survive & reproduce
    d. Members of a population compete for food, space, mates…
  • Variations that make adaptation possible are those that are passed on generation to generation
  • Extinction occurs when previous adaptations are no longer suitable to a changed environment

On the Origin of Species by Darwin:

  • After the HMS Beagle returned to England in 1836, Darwin waited over 20 years to publish
  • Darwin was forced to publish Origin of Species after reading a similar hypothesis by Alfred Russell Wallace
  • Both men concluded that life forms arose by descent from a common ancestor, and       that natural selection is the mechanism by which species change and new species arise

Fossil Evidence:

  • Fossils are relics or impressions of ancient organisms
  • Most fossils are found in layers (strata) of sedimentary rock

  • The fossil record traces history of life and allows us to study history of particular organisms
  • Through radioactive dating, geologists estimate the age of the earth at about 4.6 billion years

 

ERA PERIOD EPOCH DATES
MYA		 AGE of Notes
Cenozoic Quaternary Holocene 0-2 Mammals Humans
Pleistocene  Other Mammal Species
Tertiary Pliocene 2-5
Miocene 5-24
Oligocene 24-37
Eocene 37-58
Paleocene 58-66 Extinction of dinosaurs
Mesozoic Cretaceous 66-144 Reptiles Flowering plants
Jurassic 144-208 1st birds & mammals
Triassic 208-245 First Dinosaurs
Paleozoic Permian 245-286 Amphibians End of trilobites
Carboniferous Pennsylvanian 286-320 First reptiles
Mississippian 320-360 Large primitive trees
Devonian 360-408 Fishes First amphibians
Silurian 408-438 First land plant fossils
Ordovician 438-505 Invertebrates First Fish
Cambrian 505-570 1st shells, trilobites dominant

Precambrian

 570-2,500 1st Multi-celled organisms
2,500-3,800 1st one-celled organisms
3,800-4,600

 

 

  • Fossils are at least 10,000 years old and include skeletons, shells, seeds, insects trapped in amber, imprints of organisms, organisms frozen in ice (wooly mammoth),  or trapped in tar pits (saber-toothed tiger)
  • Transitional forms reveal links between groups (Example: Therapsids were mammal-like reptiles and Pterosaurs were bird like reptiles)

pterosaur_flying.gif (50359 bytes)
PTEROSAURS

Biogeographical Evidence:

  • Biogeography is the study of the geographic distribution of life forms on earth
  • Physical factors, such as the location of continents, determine where a population can spread
  • Example: Placental mammals arose after Australia separated from the other continents, so only marsupials diversified in Australia

 

KOALA KANGAROO

 

Anatomical Evidence:

  • Organisms have anatomical similarities when they are closely related because of common descent
  • Homologous structures in different organisms are inherited from a common ancestor have have similar structures
  • Example : Vertebrate forelimbs contain the same sets of bones organized in similar ways, despite their dissimilar functions

  • Analogous structures are inherited from different ancestors and have come to resemble each other because they serve a similar function
  • Example: Bird wing & bat wing are both for flight but they are structurally different
  • Vestigial Structures are remains of a structure that is no longer functional but show common ancestry
  • Example: Humans have a tailbone but no tail

Embryological Evidence:

  • During development, all vertebrates have a post-anal tail and paired pharyngeal pouches
  • Organisms that show similarities in their embryonic development may have a common ancestry

Biochemical Evidence:

  • Almost all living organisms use the same basic biochemical molecules, e.g., DNA, ATP, enzymes …
  • Similarities in amino acid sequences, DNA codes, etc. can be explained by descent from a common ancestor

Examples of Evolution in Modern Times:

  • Peppered moth — light colored vs. dark colored (industrialization influence) Manchester, England
  • Insect resistance to insecticides
  • Bacterial resistance to antibiotics

 

Darwin Events AP

 

Darwin Day Events
CHARLES DARWIN

 

Darwin Trivia Game Questions:

 

When was Charles Darwin born?
What was the name of the ship on which he was the naturalist?
What islands were the main source of his findings?
What was the complete title of his original book?
What famous American president shares the same birth date?
How long was his voyage scheduled to last?
“Darwin Trivia Game”
The Galapagos Islands

Adaptations of the Galapagos Finches
  The “Missing” Link

Darwin “Fortune” CookiesDarwin only took with him a simple microscope on the Beagle to observe microscopic organisms.
When Darwin was sixteen, his father took him out of school because he felt that Charles was wasting time, and he sent him to Edinburgh University.
Charles Darwin was born on February 12, 1809 in Shrewsbury, England.
Darwin transferred to Cambridge to study the theology of the Church of England wanting to become an Anglican priest.
“Changes From Within”

Lyrics & music by:  Nicole Higham
Sung by:  Brett Rabeneck, Bradley Wise, & Carrie Steves
Changes From Within
Verse 1:
Once I read a book, and this is what it said,
That the Origin of Species, came from Darwin’s head.
He studied all the life, from some islands of the west,
and distinguished adaptations, and who survived the best.
He was much more successful than scientists before,
And his use of common logic, convinced them even more.Chorus:
And it read:
You take two monkeys, and you put them to the test,
Check out their different habitats, and see nature at its best.
According to Darwin, a species can begin,
From an individual that changes from within.

Verse 2:
Natural selection, a theory he derived
Sys the strongest just get stronger while the weakest don’t survive.
So he published his ideas, he was sort of in a bind
There was another man, who wasn’t far behind.
Their ideas were the same, their timing coincided,
But Darwin finished first, and in the glory he delighted.

Verse 3:
About all of his theory, that I choose to sing about
Some people think it’s true, while others have their doubts.
To me it’s quite reasonable, to have either point of view
But think about it carefully, no matter what you do.
For starters think about that which, you really do believe
For me this includes a little story about Adam and Eve.

2nd Chorus:
I appreciate your patience, as an audience you’ve been kind
I bet this kind of song, wasn’t what you had in mind
I’ll leave you with this list of things that really matter most,
There’s life and love and happiness, but first the Holy Ghost.
Burying a Darwin Day Time Capsule

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Evolution Quiz 2

Name: 

Theory of Evolution 

 

 

 

True/False
Indicate whether the sentence or statement is true or false.
1.
Within populations, divergence leads to speciation.
2.
Genetic similarities between species is evidence of common ancestry.
3.
Shared common traits are a clue to common ancestry.
4.
The pelvic (hip) bones of a snake are vestigial organs.
5.
Darwin would have explained giraffes having long necks as a trait that allowed the fittest to survive.
6.
Darwin was the first scientist to propose that living things evolve.
7.
Most organisms produce more offspring than can possibly survive.
 

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
8.
The change that results in a species being better suited to its environment is known as
a.
reproduction.
c.
adaptation.
b.
variation.
d.
selection.
9.
New species form
a.
when ecological races diverge more and more.
b.
because of natural selection.
c.
when members of the same species become adapted to new environments.
d.
All of the above
10.
Natural selection causes
a.
changes in the environment.
b.
plants and animals to produce more offspring than can survive.
c.
changes in the frequency of certain alleles in a population.
d.
All of the above
11.
The theory of evolution predicts that
a.
closely related species will show similarities in nucleotide sequences.
b.
if species have changed over time, their genes should have changed.
c.
closely related species will show similarities in amino acid sequences.
d.
All of the above
12.
Mutations are important to the understanding of evolution because they increase the
a.
value of natural selection of animals
c.
use of organs in animals
b.
production of variations in animals
d.
differentiation of animal embryos
13.
The human appendix is an example of a structure that is
a.
homologous
c.
a variation
b.
acquired
d.
vestigial
14.
The modern theory of evolution supports the concept that inheritable variations within a species may result from
a.
recombination of genes during fertilization
c.
changes in autosomes
b.
use and disuse
d.
acquired characteristics
15.
The occurrence of the same blood protein in a group of species provides evidence that these species
a.
evolved in the same habitat
c.
descended from a common ancestor
b.
evolved in different habitats
d.
descended from different ancestors
16.
According to modern ideas of evolution, the fittest individuals are those that
a.
are stronger
c.
are best adapted to their environment
b.
move faster
d.
have the largest brains
17.
After all the grass was eaten, early horses had to stretch for food on trees.  Consequently these horses developed longer legs and necks. This statement is consistent with the views of
a.
Darwin only
c.
both men
b.
Lamarck only
d.
neither man
18.
It has been observed that white mice live in areas with white soil and brown mice live in areas with dark soil.  Which statement best describes the situation?
a.
All organisms tend to increase in numbers at a geometric rate
b.
In each generation, the number of individuals in a species remains constant
c.
There is a struggle to survive
d.
Variations are passed to offspring.  Favorable variations aid survival and reproduction
19.
Squirrels on the north rim of the Grand Canyon differ in many respects from those on the south rim (the river prevents passage from one to the other).  Which statement best describes the situation?
a.
In each generation, the number of individuals in a species remains constant
b.
Variations, which may be inherited, are found among individuals in each species
c.
The inheritance of favorable variations may eventually lead to the development of a new species
d.
All organisms tend to increase in numbers at a geometric rate
20.
The idea of the survival of the fittest is part of the explanation of the theory of evolution called
a.
use and disuse
c.
natural selection
b.
inheritance of acquired characteristics
d.
continuity of the germ plasm
21.
The process of change with time during successive generations among living things is
a.
evolution
c.
extinction
b.
law of use and disuse
d.
none of these
22.
Which of the following is an example of a morphological adaptation?
a.
hibernation
c.
an enzyme
b.
crab’s claws
d.
migration
23.
Competition between individuals of a species occurs primarily because of
a.
a scarcity of resources
c.
low birth rates
b.
advantageous variations
d.
acquired characteristics
24.
The book, Origin of the Species, was written by
a.
Charles Darwin
c.
Jean Baptiste de Lamarck
b.
Alfred Russell Wallace
d.
Thomas Malthus
25.
Variation is most important to Darwin’s theory of evolution because it
a.
provides material on which natural selection acts
b.
allows individuals to explore new habitats
c.
minimizes competition within a species
d.
allows individuals to make the best use of limited resources
26.
Evolutionary change is a(n)
a.
assumption
c.
collection of hypotheses
b.
fact
d.
debatable opinion
27.
Unlike Lamarck’s theory of evolution, Darwin’s theory included the idea
a.
that species change over time
b.
of natural selection
c.
that acquired characteristics are inherited
d.
that organisms change by a desire to better themselves
28.
According to Darwin, the process in which organisms best suited to their environment survive and reproduce is called
a.
convergent evolution
c.
natural selection
b.
divergent evolution
d.
artificial selection
29.
Genes that are active during the early development of fishes, birds, and humans are the shared heritage from a(an)
a.
fish
c.
common ancestor
b.
bird
d.
early human
30.
Darwin began to formulate his concept of evolution by natural selection after
a.
experimentation with animals.
b.
observations of many species and their geographical location.
c.
reading the writings of Wallace.
d.
agreeing with Lamarck about the driving force behind evolution.
31.
Charles Lyell’s work suggests that
a.
Earth is many millions of years old.
b.
Earth is several thousand years old.
c.
all fossils were formed in the last 1000 years.
d.
all rocks on Earth contain fossils.
32.
Which is a major concept included in Lamarck’s theory of evolution?
a.
Change is the result of survival of the fittest.
b.
Body structure can change according to the actions of the organism.
c.
Population size decreases the rate of evolution.
d.
Artificial selection is the basis for evolution.
33.
An adaptation is an inherited characteristic that can be
a.
physical or behavioral.
b.
physical or geographical.
c.
acquired during the organism’s lifetime.
d.
the result of artificial selection.
34.
The hypothesis that species change over time by natural selection was proposed by
a.
James Hutton.
b.
Jean-Baptiste Lamarck.
c.
Thomas Malthus.
d.
Charles Darwin.
35.
Charles Darwin’s theory of evolution explains all of the following EXCEPT
a.
how species become extinct.
b.
how inherited traits are passed from parent to offspring.
c.
how species change over time.
d.
how evolution takes place in the natural world.

 
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Cow Eye Dissection Worksheet

 

Cow Eye Dissection
Worksheet

 

1. Tell three observations you made when you examined the surface of the eye:

  1. ______________________________
  2. ______________________________
  3. ______________________________

2. Identify the following structures:

  1. cornea
  2. tear gland-
  3. optic nerve
  4. iris-
  5. pupil-
  6. retina

3. Name the three layers you sliced through when you cut across the top of the eye:

  1. ______________________________
  2. ______________________________
  3. ______________________________

4. Match the following parts of the eye to their function: (ciliary body, sclera, iris, retina, lens, & tapetum lucidum)

____________________ Contains the photoreceptors for vision.
____________________ The colored portion of the eye.
____________________ This structure changes shape to focus light on the retina.
____________________ The opening in the iris through which light passes.
____________________ The iridescent portion of the choroid layer in nocturnal animals.
____________________Consists of muscles, which control and shape the lens.
____________________ The white of the eye.

4. Use the pictures below to name the parts of the eye:

  1. ________________________________________
  2. ________________________________________
  3. ________________________________________
  4. ________________________________________
  5. ________________________________________
  6. ________________________________________
  7. ________________________________________
  8. ________________________________________
  9. ________________________________________
  10. ________________________________________
  11. ________________________________________
  12. ________________________________________
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Clam Dissection Questions

 

 

  Clam Dissection Questions

 

Pre-lab:
1. Give the kingdom, phylum, and class for the clam.

 

2. Describe the body of bivalves.

3. How do bivalves move?

4. Why are they called bivalves?

5. Is their digestive tract complete or incomplete?  Explain your answer.

 

6. Do bivalves show cephalization?  Explain your answer.

 

7. What are siphons & what is their purpose?

 

8. How can you distinguish a mussel from a clam?

 

9. Adults are usually sessile, but the larva or _________________ is free-swimming.

10. Are bivalves protostomes or deuterostomes?

11. Their body cavity is called the _____________ cavity.

12. Body organs make up the ___________ mass and are protected by the _____________ which secretes the ___________.

13. Is circulation open or closed?

14. Give several examples of bivalves.

Lab Questions:
1. What is the oldest part of a clam’s shell called and how can it be located?

 

2. What do the rings on the clam’s shell indicate?

3. Name the clam’s siphons.

4. What holds the two shells together?

5. What muscles open & close the clam?

6. Describe the inside lining of the shell.

7. What is the function of the tooth-like projections at the dorsal edge of the clam’s valves?

8. Where is the mantle located in the clam?  What is its function?

 

9. Describe the clam’s foot.

 

10. What is the mantle cavity?

 

11. How do clams breathe?

12. What helps direct water over the gills?

13. Where are the palps found and what is their function?

 

14. Describe the movement of food from the current siphon through the digestive system of the clam.

 

 

15. Where is the clam’s heart located?

 

16. What are the parts of the clam’s nervous system?

 

17. Why are clam’s referred to as “filter feeders”?

 

18. Label the internal structures of the clam and draw arrows showing the pathway of food as it travels to the clam’s stomach:

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