TOPIC: Evolution
AIM: Explain the theory of Natural
Selection.
Do Now: Root Word Organizer:
Homozygous and Heterozygous
Take out the Genetic Engineering ISN
HW: Selective Breeding ISN
Punnett Square Lab due tomorrow
CL Genetics due Monday
Human gene for insulin
Bacterial DNA
Bacterial that
produce insulin
Mitosis
1. According to this
evolutionary tree, which
species is the common
ancestor?
Protists
2. Which 2 species are most
closely related?
a. Flatworms and Sponges
b. Mollusks and Annelids
c. Annelids and Arthropods
d. Rotifers and Cnidarians
3. Which species is more
complex?
a. Protists
b. Rotifers
c. Echinoderms d. Mollusks
Lamarck
• First person to
propose a theory of
evolution.
–Inheritance of
acquired traits.
–Theory of use and
disuse.
(because of a
need)
Weismann
• Acquired
characteristics are
NOT passed on to
offspring
• Cut off the tails of
mice for 22
generations
– Offspring born with
tails
Charles
Darwin
• 1830’s
• Studies on Galapagos
Islands
Darwin’s Model of Evolution
Darwin observed a 13 species of finches
that were all similar except for differences in
body size, beak shape and eating habits.
• Adaptation:
A variation (inherited trait) that
makes an organism better suited
to its environment
• Ex: Camouflage
Leaf-tailed gecko
Ducks are birds that have waterproof
feathers. They live on a pond and on land.
Kangaroos
Habitat: Dry inland Australia,
including deserts and grasslands
Adaptations:
•They are able to go with out
drinking as long as green grass is
available and it adapts well to
drought.
•They can hop as fast as 40 mph
(64 km). They use this as their first
line of defense.
•The tail serves as a balance when
the animal leaps and as a prop
when it stands.
1. The 5
points to
Darwin’s
Theory of
natural
Selection.
Write the
name of
each point
in the
spaces
provided.
1. One of the prime motives for all species is to
reproduce and survive, passing on the genetic
information of the species from generation to
generation. When species do this they tend to
produce more offspring than the environment
can support.
OVERPRODUCTION
2. Darwin noted many differences in the species
he observed on his trip to the Galapagos Islands.
VARIATION
• Ex: Polar bears with thicker fur
• Darwin wasn’t able to explain
where variations came from
TOPIC: Evolution
AIM: Explain the theory of Natural
Selection.
Do Now: Pass up your Punnett Square Lab
HW: Selective Breeding ISN
CL Genetics due Monday
Genetics Exam Tuesday
1. The letter X most likely represents
(1.) bacterial cells that are unable to synthesize insulin
(2.) human cells that are able to synthesize antibodies
(3.) bacterial cells that are able to synthesize insulin
(4.) human cells that are unable to resist antibiotics
2. What is this process an example of?
Genetic engineering
Which sequence shows the largest
structure to the smallest
structure?
1.gene – DNA – chromosome
2.DNA – gene – chromosome
3.gene – chromosome – DNA
4.chromosome – gene – DNA
White short-horned cattle and Black
Angus cattle have been crossed to
produce offspring with superior beef and
rapid growth qualities.
Identify technique used. Support your
answer.
3. The lack of resources to nourish these individuals
places pressure on the size of the species population,
and the lack of resources means increased
competition and as a consequence, some organisms
will not survive.
COMPETITION
4. The organisms that die as a consequence of this
competition were not totally random. Darwin found that
those organisms more suited to their environment
were more likely to survive.
SURVIVAL OF THE FITTEST
5. Overtime, the offspring of individuals with
helpful variations make up more of a population
and eventually may become a separate species.
SPECIATION
2. Describe • Not suited for the environment.
the reason • Not able to compete
why
organisms
do not
survive,
according to
Darwin.
3. Identify
an
example of
variation
you have
observed
in a
species.
4. Why
does
Darwin
believe
organisms
“evolve?”
• They evolve to suit their
environment.
5. State
Darwin’s
Theory of
natural
Selection.
• Organisms with favorable
adaptations survive, reproduce,
and pass on the trait to offspring.
• Organisms with unfavorable
adaptations do not survive.
TOPIC: Evolution
AIM: Explain the theory of Natural
Selection.
Do Now: Take out your Selective Breeding
ISN.
Pedigree chart Ditto #’s 1 and 2
HW: Right side of genetics ditto.
1. Beth does not have green hair. Is she a
carrier? Explain.
Yes she is a carrier.
All of her offspring have green hair, so she is
carrying one recessive allele.
2. Bunny, who has blond hair, is a carrier of the green hair
gene. She claims to be the long lost child of Great Grandma
and Great Grandpa Berg. Should they include her as a
daughter in their will? Explain.
No. Great Grandma and Great Grandpa Berg are
homozygous recessive so Bunny should have green hair if
she is their daughter.
1. What are the genotypes of the individuals
from generation 1?
2. Could generation 2 have any carriers?
3. What are the genotypes of the parents in
generation 3?
Y
1. What process is represented in the diagram?
Genetic engineering.
2. Identify structure Y.
Recombinant DNA
3.What does X represent?
Bacteria that produce insulin
4. Identify the cell division occurring in this process.
Mitosis
1. Identify the finch that
lives on an island with
fruit as the main source
of food.
2. Identify the finch that
lives on an island with
cacti as the main
source of food.
3. Describe what occurs
on an island inhabiting
small ground finches
and medium ground
finches.
4. Can vegetarian finch
and large ground
finches inhabit the
same island? Support
your answer.
1. Identify the finch
that lives on an
island with fruit
as the main
source of food.
Support your
answer.
Vegetarian finch
They have parrotlike beaks.
2. Identify the finch
that lives on an
island with cacti as
the main source of
food. Support your
answer.
Cactus ground
finch
They have
probing bills.
3. Describe what occurs
on an island inhabiting
small ground finches and
medium ground finches.
The finches will
compete for food.
4. Can vegetarian finch
and large ground finches
inhabit the same island?
Support your answer.
Yes.
They eat different types
of food.
Overproduction
Competition
Survival of the
Fittest
Speciation
6. There are 2 types of worms: worms that eat at night
(nocturnal) and worms that eat during the day (diurnal). Birds
eat during the day and seem to be eating only the diurnal
worms while the nocturnal worms are in their burrows. Each
spring when the worms reproduce, that have about 500
babies but only 100 of these ever become old enough
become old enough to reproduce.
a. Identify the worm that natural selection selected
AGAINST and support your answer.
Diurnal worms.
Birds come to eat the worms during the day.
The nocturnal worms are in the soil during the
day.
6. There are 2 types of worms: worms that eat at night
(nocturnal) and worms that eat during the day (diurnal). Birds
eat during the day and seem to be eating only the diurnal
worms while the nocturnal worms are in their burrows. Each
spring when the worms reproduce, that have about 500 babies
but only 100 of these ever become old enough become old
enough to reproduce.
b. Identify the points of Darwin’s theory of Natural
Selection below from the scenario above.
• Variation: Two types of worms (Nocturnal and diurnal)
• Overproduction: Worms produce 500 babies, but only 100 become
old enough to reproduce.
• Competition: Worms competing for food
• Survival of the fittest:
Nocturnal worms have the favorable adaptation.
c. If speciation were to occur, identify the
characteristic that the species would have.
Worms would be nocturnal because they were
not eaten by the birds.
8. There are 2 types of rabbits: those that strictly eat grass and
those that strictly eat berries and flowers. A drought occurs one
year, and the plants have difficulty producing any extras
(flowers, berries, etc.) and remain green. The rabbits have
reproduced all year, but many are eaten by foxes or hawks.
Due to the drought, many rabbits have starved to death.
a. Identify the rabbits that natural selection selected AGAINST
and support your answer.
The rabbits that strictly eat berries and flowers were
selected against. Because of the drought, berries and
flowers were not produced. Therefore, these flowers did
not have food to eat,
8. There are 2 types of rabbits: those that strictly eat grass and
those that strictly eat berries and flowers. A drought occurs one
year, and the plants have difficulty producing any extras
(flowers, berries, etc.) and remain green. The rabbits have
reproduced all year, but many are eaten by foxes or hawks.
Due to the drought, many rabbits have starved to death.
b. Identify the points of Darwin’s theory of Natural
Selection below from the scenario above.
Rabbits that eat grass and rabbits that eat berries
• Variation: and fruit
• Overproduction: Rabbits have reproduced all year.
• Competition: Rabbits compete for food
• Survival of the fittest:
Rabbits that eat grass had the favorable adaptation
and, as a result, survived and passed on their trait to
offspring.
c. Describe which rabbits would have greater
population during the drought. Support your
answer.
The rabbits that eat grass will have a greater
population during the drought because they
have food to eat.
Let’s summarize…
1. According to Darwin’s theory of Natural
Selection, which organisms survive?
2. Identify the main points to Darwin’s Theory
of Natural Selection.
The diversity within the wild bird species in
the diagram below can best be explained by
which process?
(1) natural selection
(3) ecological succession
(2) asexual reproduction (4) mitotic cell division
Which concept would be correctly placed in
box X?
(1) use and disuse
(2) variation
(3) transmission of acquired traits
(4) changes in nucleic acids
Which statement is not part of the
concept of natural selection?
(1) Individuals that possess the most
favorable variations will have the best
chance of reproducing.
(2) Variation occurs among individuals in a
population.
(3) More individuals are produced than will
survive.
(4) Genes of an individual adapt to a
changing environment
According to the theory of natural selection,
why are some individuals more likely than
others to survive and reproduce?
(1)Some individuals pass on to their offspring new
characteristics they have acquired during their
lifetimes.
(2)Some individuals are better adapted to exist in
their environment than others are.
(3)Some individuals do not pass on to their
offspring new characteristics they have acquired
during their lifetimes.
(4)Some individuals tend to produce fewer
offspring than others in the same environment.
Charles Darwin proposed that organisms
produce many more offspring than can
possible survive on the limited amount of
resources available to them. According to
Darwin, the offspring that are most likely
to survive are those that
(1.) are born first and grow fastest
(2.) are largest and most aggressive
(3.) have no natural predators
(4.) are best adapted to the
environment
Darwin's studies of finches on the Galapagos
Islands suggest that the finches' differences
in beak structure were most directly due to
(1.) acquired characteristics in the
parent finches
(2.) the size of the island where the
finches live
(3.) mating behaviors of the
different finch species
(4.) adaptations of the finches to
different environments
According to Charles Darwin, one
factor that affects the evolution of
a species is
(1.) variation due to genetic mutations
(2.) rapid fossil formation
(3.) survival of the fittest
(4.) exposure to environmental pollutants
1. How many people in this pedigree chart have the
recessive trait?
2. How many people in this pedigree chart are carriers?
3. How many offspring are found in generation 2?
4. What is the chance of the individuals in generation 1
having a child with the recessive trait?
1. How many individuals
make up generation
2?
2. What are the
genotypes of the
individuals in
generation 1?
3. How many individuals
make up generation
3?
Gorillas
Habitat: Tropical forest
Adaptations:
•Opposable thumb enables
manipulation of objects; big toe
also opposable for grasping.
•Large and powerful arms used to
break stalks or uproot vegetation
while foraging.
•High intelligence probably an
adaptation for finding scarce or
isolated fruit plants in the rain
forest.
Cactus
Habitat: Dry deserts
Adaptations:
•The spines serve a number of
purposes in addition to protection
from hungry and thirsty animals.
•They provide shade, serve as a
windbreak to prevent dehydration
from dry winds, and help trap warm
air close to the plant.
•The root systems of cacti are very
close to the surface of the soil,
making it possible for them to take
advantage of the slightest rain
shower.