Transcript BiodiversityClassification - Ms. Nakamura`s Biology Class Wiki

D.N.A (LET’S CLASSIFY) ROOT WORD – DI (apart/away)
Objective: SWBAT explain how phylogenetic trees and
cladograms are graphical representations of evolution
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Organize/ group the following ice cream flavors in any
way that makes sense to you.
Example: Start broad (how are they all related) to
more specific
Vanilla
Chocolate
Rocky Road
Mint Chocolate Chip
Cookies and Cream
Rainbow
D.N.A please write on a separate sheet of
paper
Reflection Questions
(Use Complete Sentences!)
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How do you believe you performed on the unit exam?
What came easy to you? What parts were more
difficult?
How did you prepare for the exam?
What can you improve on when preparing for the next
exam?
What can Ms. Nakamura do to improve?
Unit 2: Diversity of Organisms
CLASSIFYING LIFE’S DIVERSITY –
BUILDING DARWIN’S TREE OF LIFE
Phylogeny & Systematics
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Phylogeny
 evolutionary
history of a species
 based on common ancestries inferred from
 fossil
record
 morphological & biochemical resemblances
 molecular evidence (DNA)
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Systematics
 Using
phylogeny as an analytical approach to the
study of the diversity of life and relationships
between organisms
2004-2005
Fossil record
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Sedimentary rock are richest source of fossils
 fossil
record is a substantial, but incomplete, chronicle
of evolutionary history
 incomplete
historical documents of biology
 history
of life on Earth
is punctuated by
mass extinctions
5000 year old ice mummy found on an Alpine
ridge dividing Austria from Italy at 10,5002004-2005
feet
above sea level.
Two approaches
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1) Linnean system of groups
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2) Phylogenic Trees/Cladistics
Systematics
 Connecting
classification to
phylogeny
hierarchical system
 Carolus Linnaeas
(taxonomist who
named and classified
species)
 latin binomial
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 genus (Homo)
 Species (sapiens)
2004-2005
#1 – Linneaus and taxa
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Taxa – group names that we create to classify
organisms
domain  kingdom  phylum  class  order 
family  genus  species
Keep Pond Clean Or Froggy Gets Sick!
Early systems primarily based on structural analysis
(anatomy – dissections by surgeons)
Binomial nomenclature rules
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Organism’s scientific name: Felix catus
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Genus = Felix, species =catus
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Humans: Homo sapiens
Problems with Linnean system
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Analogous structures result in mis-classifying
Transitional organisms strain the definitions of
groups
 Ex:
Platypus – the egg-laying mammal (or should that
be mammary-gland containing reptile?)
A challenge for biologists
Analogy
Homology
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Shows deep relatedness,
common ancestry
Similar components or
materials – may now
serve different functions
Shows divergence from
ancestry
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Superficial relatedness
Components or structure
significantly different
Shows convergence from
separate ancestries
Example of analogy
European mole
(mammal)
Australian mole
(marsupial)
similar adaptations to live in
current environment (underground), but very
different ancestries
Homology
Divergent evolution
modern related species
Analogy
Convergent evolution
superficially related
species (may live in
similar environment)
common
ancestor
different
ancestries
Building
phylogentic
trees
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Connection
between
classification &
phylogeny
Tracing possible evolutionary
relationships between some
of the taxa of the order
Carnivora, a branch of the
class Mammalia.
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•Each branch point
–Represents the divergence of two species
Leopard
Domestic
cat
Common ancestor
•“Deeper” branch points
–Represent progressively greater amounts of
divergence
Wolf
Leopard
Common ancestor
Domestic
cat
Cladistics
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Depiction of patterns of shared characteristics
among taxa (groups)
Organisms at base of cladogram share ancestral
traits of others (primitive character)
Organisms further up cladogram have additional derived
traits
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(present in an organism but not in the previous common
ancestor)
the lung / lung
the mammal clade
the the
jaw
amniote
the
clade
tetrapod
clade
derivative
cladeclade
Cladistics
lamprey
shark
tuna salamander turtle
outgroup – representative
with no further derived traits
in cladogram, but
fundamental similarities to
others
dogs
lampreys
salamanders
sharks
tuna
turtles
total
“no”
4 limbs?
air sac?
yes
no
yes
no
no
yes
3
yes
no
yes
no
yes
yes
2
amniotic
egg?
yes
no
no
no
no
yes
4
jaws?
yes
no
yes
yes
yes
yes
1
mammary
glands?
yes
no
no
no
no
no
5
common
amniote
ancestor
dog
common
evolution
ancestorof
amniotic
with 4 egg
legs
evolution
commonof
ancestor
tetrapody
(4sac
legs)
with an air
common
evolution
of ancestor
air sac
withbladder)
a jaw
(swim
evolution
ofancestor to
common
jaws
all these animals
evolution
of
connection
to other
mammary
organisms
on tree
glands
Cladistics
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What is a valid clade?
Any group that includes all modern derived species
and their common ancestor
In many cases, Linnean taxa are valid clades
(ex: vertebrates, mammals)
In some cases, they are NOT valid clades
(ex: protists, prokaryotes, reptiles)
One last misconception
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“Humans evolved from chimpanzees”
No, they are both modern species … BOTH evolved
to their modern forms from a common ancestor more
recent in history than other species
chimpanzees
humans
common
ancestor
the rest of the primates, mammals,
vertebrates, and all other life really
D.N.A
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Take 5 minutes to compare and contrast your
cladogram with a partner
Discuss why you placed the organism the way you
did based off of the derived trait
Cladistics
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Homoplasy: a shared character trait that was
not been inherited from a common ancestor
 Results from convergent evolution
 Results from evolutionary reversal
Cladistics
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Other Phylogenetic Methods
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Evolutionary changes occur in a clock-like fashion
Mutations may build up in any given stretch of DNA
at a reliable rate.
 Ex:
The gene that codes for the protein alpha-globin
(part of hemoglobin) experiences base changes at a rate
of .56 changes per base pair per billion years.
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Molecular clock: rate of evolution of a molecule is
constant through time
D.N.A
- Objective:
SWBAT create and design an AP
Biology FRQ essay IOT receive the maximum points on the AP
exam
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For the hemoglobin protein, the following
information was given about the differences in
amino acid sequences between organisms.
Human
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Baboon
Chimpanzee
Lemur
Gorilla
Dog
Chicken
Frog
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0
9
1
10
13
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Draw a possible cladogram illustrating the
relationship of these organisms to a common
ancestor and summarize what can be obtained from
this specific cladogram in a paragraph.
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GREAT DISCUSSION!
Love,
AYE AYE
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“Winnie the Pooh” – source of
attraction beginning at a young
age
“Yes, I believe that as humans we
tend to show favoritism to things
that are more attractive because
that is how we choose our
mates…”
Importance to the ecosystem
Oleander flower – pretty in
appearance, but poisonous…looks
can be deceiving!
How about a rat?
Writing AP Biology Free Response Essays
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1. READ THE QUESTION
2. OUTLINE the answer
3. Define your terms
 Underline
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your key terms
4. Answer each subject/point in detail!
5. GET TO THE POINT!
 Background
instructed to
information is not necessary unless
REVIEW FROM LAST CLASS
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What are the three hypothesis in regards to the
origin of life?
1) SPECIAL CREATION, 2) EXTRA-TERRESTRIAL ORIGIN, 3) SPONTANEOUS
ABIOTIC ORIGIN
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What were the key events in the origin of life?
1) ORIGIN OF CELL (PROTOBIONTS), 2)ORIGIN OF GENETICS, 3)
ORIGIN OF EUKARYOTES
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How did endosymbiosis affect the origin of life of
eukaryotes?
MUTUAL BENEFICIAL RELATIONSHIP!
REVIEW FROM LAST CLASS
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How are fossils beneficial in evolution?
AGE AND MORPHOLOGIES (APPEARANCES) OF FOSSILES SHOW
PATTERS OF CHANGES THAT HAVE OCCURRED BETWEEN SPECIES
(RELATIONSHIP!)
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What are the two major hypotheses on how
evolution takes place?
GRADUALISM AND PUNCTUATED EQUILIBRIUM
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How are they different from each other?
GRADUALISM – organisms evolve through a slow and constant
change
PUNCTUATED– species evolve very rapidly