Name __________________________________
NOTES 16.4 EVIDENCE OF EVOLUTION
Period _______ Date ____________ Seat _____
Comparative Embryology: The study of the
similarities and differences among various
organisms during embryonic development.
A.
Rabbit
B.
Human
Homologous Structures:
Structures that are similar
In different species of common ancestry.
C.
Chicken
Different
functions
Pharyngeal pouches
Analogous Structures:
Features (like wings) of
different species that are similar in how they
function (flight), but the structures of the features
are different (covering: skin, feathers, chitin).
Pharyngeal pouches in embryos can develop into
gill arches
____________________
(fish) or straining device
sea squirts
(____________________)
or the jaw, middle ear
Humans
bones, and rings of the trachea (____________).
Sea squirt
5 cm
1
Skin
Feathers
Layers of chitin
Name __________________________________
NOTES 16.4 EVIDENCE OF EVOLUTION
Vestigial Structures:
Period _______ Date ____________ Seat _____
Atavistic Structures: The reappearance of a
trait that has been lost during evolution.
A structure that is reduced
in size and has little or no original function.
Whale hip
Snake hip
Black Vine Weevil
fused wing covers
Skink (useless legs)
Human tail with
vertebrae
Ostrich wings
Dog
Dolphin with
hind fins
Supernumerary
nipples in
humans
DNA
Common Genetic Code: All living cells use _________
and RNA to make _________________
and pass on
Proteins
genetic information. The genetic code is nearly the
same
______________
for all living things.
Human
Nictitating
membrane
2
Name __________________________________
NOTES 16.4 EVIDENCE OF EVOLUTION
Period _______ Date ____________ Seat _____
A molecule found in
Homologous molecules:
different species that has a similar
structure and
estimates
function.
Inherited anomalies:
Mutations and viral insertions
that are inherited from a common ancestor.
Cytochrome C is found in
all living cells. It is involved
in cellular respiration.
Works
fine!
Origin of pseudogene
sweets
All of the cats above cannot taste __________________.
deletion
Each has an identical 247 base-pair _________________
in their Tas1r2 (taste receptor) gene. This causes a
frame-shift
___________________
mutation, which results in a
stop
premature ___________
codon. The cats inherited this
common _____________.
ancestor
condition from a _____________
Yeast
inserted the human Cytochrome C.
Scientists ___________
gene
____________into
other organisms and found
functioned
that the protein ___________________
very well.
100%
The Cytochrome C amino acid sequence is ______
identical in both humans and chimpanzees.
Identical viral insertions appear in different __________
species at
the same locations within their _______.
These animals
DNA
inherited these insertions from a common ancestor.
____________
Hemoglobin is a protein in
the blood that transports
oxygen to cells.
100%
The hemoglobin amino acid sequence is ______
identical in both humans and chimpanzees.
Insertions
3
Name __________________________________
NOTES 16.4 EVIDENCE OF EVOLUTION
Period _______ Date ____________ Seat _____
Age of the Earth: Radiometric dating estimates
the age of the Earth to be about 4.5 billion years old.
Not for dating rocks, but good
for organic artifacts like:
Iceman = 5,300 ya
Kennewick man = 10,000 ya
Cro Magnon fire pit = 28,000 ya
Useful for dating
age of the earth
U =75%
0 half-lives
(rock crystallizes)
U =50%
1 half life
(710 myo)
0.5 half-lives
(355 million years old)
U =12.5%
3 half lifes
(2,130,000,000 myo
Or 2.31 byo)
4
Sea shells are
between
355 – 370
mya
Trilobites are
between
485 – 510
mya
355 mya
Name __________________________________
NOTES 16.4 EVIDENCE OF EVOLUTION
Whale Evolution
ankle
Double pulley ___________
bones called astragalus are found
pronghorn
in 35 myo whales and modern ________________
antelopes.
The same structure can be seen in the hind foot of a 33 myo
Basilosuarus
________________________
whale. This evidence suggests
distantly
whales and pronghorns are _________________
related.
blowhole
The evolution of the _________________
in whale-like
creatures over time to its current position at the top of
dolphin
the head as shown in a modern __________________.
5
Period _______ Date ____________ Seat _____