2. Ch. 6.3 Evidence of Evolution foldable:
• Create 6-tab foldable
• Label front of tabs at top:
– Homologous structures
– Analogous structures
– Vestigial structures
– Developmental biology (embryology)
– Comparing DNA sequences
– Divergence
• On inside of tabs:
– Description
– How it supports theory of evolution
3. • As fossils were discovered, patterns emerged
that showed many different species with
similar body structures.
• Evidence suggests that species change over
time.
• Change over time = Evolution (to evolve)
• Biological evolution is the change over time
in populations of related organisms.
What causes species to change over
time?
4. • Comparative Anatomy – the study of similarities
and differences among structures of living species.
• Homologous Structures – body parts are similar in
structure, but different in function
Comparative Anatomy
5. The forelimbs of these species are different sizes, but
their placement and structure suggest common
ancestry.
Evidence: More similar structures = more related
species (evolved from common ancestor)
8. What term refers to body parts of organisms
that are similar in structure and position but
different in function?
A. B. C. D.
0% 0%0%0%
A. Camouflage
B. Mimicry
C. Analogous structures
D. Homologous structures
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9. Vestigial structures are body parts that
have lost their original function through
evolution.
Comparative Anatomy
10.
11. Section 1 Change over Time
Evidence: shows relation to ancestors who
used the part for a specific purpose
12. Which of the following is NOT evidence that
whales evolved from mammals that once
lived on land?
A. B. C. D.
0 000
A. fossil discoveries that link
whales to mammals
B. the hip bones of whales
C. the fishlike shape of whales
D. the fact that whales are
mammals
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13. Studying the development of embryos can
also provide scientists with evidence that
certain species are related.
Embryology – The science of the
development of embryos from fertilization
to birth
Evidence: similarities in development of
parts show relatedness
Developmental Biology
14. All vertebrate embryos exhibit pharyngeal
pouches at a certain stage of their development.
In reptiles, birds, & humans, pharyngeal pouches
develop into a gland in the neck – in fish, they
form gills. (both glands & gills regulate calcium)
2. How are Earth’s organisms related?
17. What term refers to body parts that perform
a similar function but differ in structure?
A. B. C. D.
0% 0%0%0%
A. Analogous structures
B. Homologous structures
C. Pharyngeal pouches
D. Vestigial pelvis
45
18. • Molecular biology is the study of gene
structure and function.
• Discoveries in molecular biology have
confirmed and extended much of the
data already collected about the theory
of evolution.
• Comparing DNA Sequences: Scientists
compare the similarity of genes (DNA) &
proteins to study the relatedness of living
species.
Molecular Biology
19. Aligned DNA fragment and first chromosome banding patterns for man (Homo
sapiens), chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla), and orangutan
(Pongo pygmaeus).
Evidence: the more similar the DNA is, the
more related the species
20.
21. Divergence: Using the rate
of DNA mutations (“molecular
clock”) to estimate when
species changed
Molecular data indicate that
whales and porpoises are
more closely related to
hippopotamuses than they
are to any other living
species.
Molecular Biology
~55
Evidence: shows how closely related
species are to each other
22. When was the last time Whales and Even-
toed hoofed mammals shared a common
ancestor?
0%
0%
0%
0% A. 35 mya
B. 50 mya
C. 65 mya
D. 75 mya
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23. 2 Views on the rate of natural selection:
A. slowly and steadily
B. change occurs in short bursts after long
periods of stability.
24. • The fossil record is still incomplete, but new fossils
are being discovered all the time.
• For example, the Tiktaalik fossil has both fish and
amphibian features – linking the 2.
• Most evolution research is now done at the molecular
level, but Darwin’s basic principles still hold true after
150+ years.
25. What evidence suggests that humans are
more closely related to chimpanzees than
any other animal?
A. B. C. D.
0% 0%0%0%
A. Analogous structures
B. Homologous structures
C. DNA sequences
D. Vestigial structures
45
Editor's Notes
Tiktaalik roseae, better known as the "fishapod," is a 375 million year old fossil fish which was discovered in the Canadian Arctic in 2004. Its discovery sheds light on a pivotal point in the history of life on Earth: when the very first fish ventured out onto land.
Tiktaalik has a mix of fish and amphibian traits
Tiktaalik looks like a cross between the primitive fish it lived amongst and the first four-legged animals (a group called "tetrapods" from tetra-, meaning four, and -pod, meaning foot. Actually, all animals that descended from these pioneer amphibians, including us, can be called tetrapods). Tiktaalik lived about 12 million years before the first tetrapods (which are approximately 363 million years old). So, the existence of tetrapod features in a fish like Tiktaalik is significant because it marks the earliest appearance of these novel features in the fossil record.
Human genes are 96% similar to chimpanzees and 85% similar to mice. There’s a gene (FOXP2 gene) that controls speech development in people (learning how to move our mouths & tongues to produce speech), song in birds, and learning sequences of rapid movement for mice.
