Transcript Clues About Evolution

Clues About Evolution
What is a paleontologist?
• A paleontologist is a
scientist that studies
ancient life by looking
for and examining
fossils.
What are the five types of
fossils?
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Imprint fossils
Mineralized fossils
Frozen fossils
Amber fossils
Cast fossils
Why are most fossils found in
sedimentary rock?
• Igneous and
metamorphic rocks are
created by exposure to
heat. This heat would
destroy any pant or
animal tissues before
they could fossilize.
Because new rock forms on top
of old rock, fossils found in the
lower layers of sedimentary rock
will almost always be older.
Of all the plants and animals that
have ever lived on Earth, 99 %
are now extinct.
Various Fossils
Other Supporting Evidence
• The embryos of fish,
birds, reptiles, and
mammals are virtually
indistinguishable from
each other early in
their development.
Homologous Structures
• Body parts that animals have in common
even though they might be different
variations of the same thing.
Vestigial Structures: body parts
that animals have in common
even though they may never used
them.
DNA
• Similar DNA among
species suggest a
common ancestor
somewhere along the
evolutionary line.
More Fossils…