Transcript Evolution PowerPoint Presentation updated

Evolution
ClipBird Lab
Biology
Evolution Unit
Day 5
ClipLand Scene

Here we see a new species called ClipBirds.

They were tragically split into two
populations---the East ClipLand and the
West ClipLand.

How are these birds alike? How are they
different?
http://www.ucmp.berkeley.edu/education/lessons/clipbirds/scene.pdf
Food Values
Food Values in Megacalories
Marblefruit
10
Big Tootfruit
5
Tiny tootfruit
2
Megacalories Needed
To Survive
To Reproduce
Big bill
80
160
Medium bill
50
100
Small Bill
25
50
ClipBird Populations
West Clipland
1st Season 2nd Season
3rd Season
4th Season
3rd Season
4th Season
Big Bill
Medium Bill
Small Bill
East Clipland
1st Season 2nd Season
Big Bill
Medium Bill
Small Bill
Discussion


What happened to these populations?
What factors had an impact on their
lifestyles?
Vocabulary

Adaptation- inherited trait that increases a
population’s chances of survival and
reproduction in a particular environment.
–
What types of adaptations did we see here?
Vocabulary

Niche- habitat and the role a population plays
in that habitat. Includes where organisms
live, what and how they eat, how they raise
their offspring, and what their predators are.
–
What were the examples of the niche that we saw
in this lab?
News Reporters



You are a news reporter and are writing a
story on Charles Darwin and his theory.
Need to answer the 6 questions of Who,
What, When, Where, Why, and How.
Have today during class to find your
information. Hand in by tomorrow.
Background Information

In Mediaeval times, people believed in
Spontaneous Generation.

Idea that living things could come from non-living
things.
Example of Spontaneous Generation

Observation: Every year in the spring, the Nile
River flooded areas of Egypt along the river, leaving
behind nutrient-rich mud that enabled the people to
grow that year’s crop of food. However, along with
the muddy soil, large numbers of frogs appeared
that weren’t around in drier times.

Conclusion: It was perfectly obvious to people back
then that muddy soil gave rise to the frogs.
Redi’s Experiment

In 1668, Francesco
Redi, an Italian
physician, did an
experiment with flies
and wide-mouth jars
containing meat.

One jar was covered
with a stopper, one was
covered with gauze,
and one was left open.
Redi’s Data



In the uncovered jars, flies entered and laid eggs on
the meat. Maggots hatched from these eggs and
grew into more adult flies.
Adult flies laid eggs on the gauze on the gauzecovered jars. These eggs or the maggots from them
dropped through the gauze onto the meat.
In the sealed jars, no flies, maggots, nor eggs could
enter, thus none were seen in those jars. Maggots
arose only where flies were able to lay eggs.
Redi’s Conclusions

Only flies can make more flies

This experiment disproved the idea of
spontaneous generation for larger
organisms.
Louis Pasteur

In1864 Louis Pasteur,
disproved spontaneous
generation in microscopic
organisms.

Pasteur boiled broth in
various-shaped flasks to
sterilize it, then let it cool. As
the broth and air in the
containers cooled, fresh room
air was drawn into the
containers. None of the flasks
were sealed — all were
exposed to the outside air in
one way or another.
Louis Pasteur’s Findings

Broth in flasks with necks opening straight
up spoiled while broth in swan-neck flasks
did not, even though fresh air could get it.

Broth in flasks with cotton plugs did not
spoil, even though air could get through the
cotton. If the neck of a swan-neck flask was
broken off short, allowing bacteria to enter,
then the broth became contaminated.
Who is Jean-Baptiste Lamarck?


1809- French Scientist who reasoned that
fossils of extinct animals were the ancestors
of those living today.
Developed a theory of evolution



Organisms are constantly striving to improve
themselves.
Use it or lose it! Most-used body structures are
maintained, while others waste away.
Inheritance of acquired characteristics.
Discussion—So What Are the Important
Aspects of Darwin’s Theory?

Natural Selection

Sexual reproduction causes variation within a species,
some of which are favorable.

There is a struggle for exsistance.

Not all young produced in each generation can survive.
(Nature overproduces)

Individuals that survive and reproduce are those with
favorable variations.
Discussion—So What Are the Important
Aspects of Darwin’s Theory?

Geological Change is slow.



These gradual geological changes can influence
plant and animal life over time.
This Theory is called Gradualism
Artificial Selection


Selective breeding of domestic animals and crops
to gain most desirable characteristics.
How does this affect us now?
Vocabulary to Know

Terms





Natural Selction
Variation
Gradulism
Artificial Selection
Spontaneous Generation

People and Theories




Darwin
Jean-Baptiste Lamark
Louis Pasteur
Francesco Redi
Add all of these terms and people to your evolution foldables!!
Lucy Activity



Where did humans come from?
Who are we related to?
Lucy, ancient hominid fossil, helps us to
bridge the gap in human evolution.
Primate Family Tree
Anthropoids
Hominoids
Hominids
Old World
African Old World
Monkeys Gibbon Orangutans Human
Apes
Monkeys
Lucy
Let’s find out more about Lucy by reading Digging up the Past
Lucy Discussion

Comparing hominids from Lucy’s lifetime to
your own, do you think there have been more
changes in physical characteristics of the
body (such as hands, feet, head, posture) or
more changes in how hominids lived (types
of shelter, ways of getting around, ways of
gathering food)?

Did Lucy use her structures the same way
that we use our own structures today?
Lucy Discussion

Which aspects of your description were
based on evidence?

Which aspects of your description were
inferences related to evidence?

Which aspects of your descriptions were
guesses?
Evidence for Evolution
Evolution of Humans
Wrong—There is no direct lineage!!
So is this correct???
No, there is no direct lineage!!
So what is right??
Anthropoids
Hominoids
Hominids
Old World
African Old World
Monkeys Gibbon Orangutans Human
Apes
Monkeys
We have a common
ancestry!
How do we know this?

Scientists have come up with multiple
ways to show evidence for this theory
of evolution.
1.
2.
3.
4.
Comparative anatomy
Comparative physiology
Fossils
Immunity resistance
Evidence for Evolution: Comparative
Anatomy

Homologous Structures

Structures that have a common origin but
not necessarily a common function.
Evidence for Evolution: Comparative
Anatomy

Vestigial Structures


Structure in an organism that seem to have
little to no obvious purpose.
Examples in humans
Tail bone
 Wisdom teeth

Evidence for Evolution: Comparative
Anatomy

Analogous Structures

Structures are similar in appearance and
function but are different in anatomical
development and origin.
Evidence for Evolution: Comparative
Physiology

DNA Comparison


95 of our DNA genome matches the DNA
genome of chimpanzees
Enzyme Comparison
Evidence for Evolution: Fossils

Fossil Record


More simple organisms appeared first
Carbon Dating
Uses the decay of carbon over time to tell
how long the fossils have been in the
ground.
 allows us to organize once living things by
age and type.


Indicates a change through time
Evidence for Evolution: Resistance
Insects have become resistant to
different types of farm chemicals
 Bacteria has become resistant to
different types of antibiotics


Natural Selection selects towards
mutations that are resistant.
Evidence for Evolution: OOPS!

Comparative Embryology
Similarities in development
= genetic similarities
 This is no longer believed
to be true!!

Population Genetics

Speciation

Evolution of one or more species from a
common ancestor -- New species created
 Species
is a group of similar-looking
organisms that can breed with one another
and produce fertile offspring
Population Genetics

Divergent Evolution (Allopatric Speciation)
 Geological
barrier separates members of the
population
 Two different species evolve
Population Genetics

Convergent Evolution
 Natural
selection produces analogical
adaptations in response to environmental
conditions.
 Two similar species
Population Genetics

Coevolution
 Environmental
factors
cause two species to
evolve together.
 Special relationships
between organisms.
Ex. Flowers and bees.
Population Genetics

Adaptive Radiation
 An
open habitat
creates many different
evolutionary tracts for
one species
 Many diverse species
from one common
ancestor.
So…How Does This Really Happen?

Evolution in Genetic Terms: The change
in allele frequencies over time.
Population Genetics

Mutations: change in
genetic information of
a cell
Population Genetics

Gene Pool: Combined genetic material of
all the members of a given population.

Allele Frequencies: Percentage of
appearance of a single allele in a gene
pool.

What is the Allele Frequency of blue eyes
in this class?
So How Do Adaptations Happen?

Natural selection allows an individual with
desirable traits to live and pass on the
genetic information.
 Person
with correct DNA will pass off their
genes to next generation
Population Genetics

Genetic Equilibrium:
If the allele frequency
is constant the allele
has reached
equilibrium. It will not
change unless
something big
happens to the
population.
Population Genetics

Genetic Drift: random change in allele frequency
in a population due to chance events.