Download 15.2 PPT Notes from class

II. Evidence of Evolution
- Evidence comes
from a wide variety
of observations.
Archaeopteryx Fossil
A. The Fossil
Record
- provides
direct
evidence for
evolutionary
relationships
A. The Fossil
Record
- provides
direct
evidence for
evolutionary
relationships
- many ‘missing
links’ have
been found
(a) Pakicetus (terrestrial)
(b) Rhodocetus (predominantly aquatic)
Pelvis and
hind limb
(c) Dorudon (fully aquatic)
Pelvis and
hind limb
(d) Balaena
(recent whale ancestor)
B. Comparative Anatomy
1) Homologous Structures:
- organs in related organisms with a
similar underlying anatomy
- examples: forelimbs of humans,
bats, whales, etc.
Homologous Structures
Flying
Swimming Running
Grasping
2)Vestigial Structures:
- organs with no apparent function
that are homologous to functional
organs in related organisms
- examples: coccyx, appendix, ear
muscles, etc.
Salamander
Vestigial Structures
Gibbon Viper
Gray Whale
C. Comparative Embryology
- Organisms with common ancestors
share similarities in embryonic
development.
Pharyngeal
pouches
Post-anal
tail
Chick embryo
Human embryo
C. Comparative Embryology
Lizard
Tortoise
Pig
Human
D. Comparative Biochemistry
- All organisms contain
DNA, RNA, and
proteins made of the
same 20 amino acids.
- The more recent two
organisms share a
common ancestor, the
more similar their DNA
and proteins.
DNA Differences
in Cytochrome C
E. Biogeography
- Biogeography explains why certain
species are found in certain places.
- Islands have many endemic species
that are often closely related to
species on the nearest mainland or
island.
Biogeogaphy of a Group of
Pacific Island Monarchs
Woolly
Opossum
Marsupial
Mouse
Wombat
Biogeography
of Marsupials
Papua New Guinea
Numbat
Marsupial Mole
Spotted Quoll
Sugar
Glider
Bennett’s
Wallaby
Koala
Australia
New Zealand
Biogeography
of Marsupials
Biogeography
of Marsupials
F. Types of Adaptation
1. Camouflage
Leafy Sea Dragon
F. Types of Adaptation
1. Camouflage
Octopus near
Cayman Island
(1:15)
.
F. Types of Adaptation
1. Camouflage
Octopus
F. Types of Adaptation
1. Camouflage
Scorpionfish
Dead Leaf Butterfly
Walking Stick
Cheetah
Mantis
2. Mimicry
- A harmless species may imitate a
harmful species.
Milk Snake
Coral Snake
2. Mimicry
- A harmless species may imitate a
harmful species.
Hawkmoth larva
Green parrot snake
- 2 harmful species may reinforce each
other’s warning colors.
Spring Salamander
Red Salamander
Gyrinophilus porphyriticus
Pseudotriton ruber
Müllerian vs. Batesian Mimicry
Median
Wasp
Hoverfly
Hoverfly
Paper Wasp
Hoverfly
Longhorn
Beetle