Download Evidence of Evolution Fossils Provide Evidence FOSSIL: The

Theory of Evolution
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Evidence of Evolution
Fossils Provide Evidence
• Animal _______________ show a _____________ of development from early ancestors to
their modern descendants.
• There are ______ in the fossil record.
• Fossils are _________.
FOSSIL: The _____________ or mineralized remains (bone, petrified
tree, tooth, or shell) or ______________ of an organism that
lived long ago.
Three Major Points
• Earth is about _________ billion years old.
• Organisms have inhabited the earth for most of its history.
• All organisms living today _____________ from earlier, simpler life-forms.
PALEONTOLOGIST: Scientist who studies ___________________.
Paleontology
• Paleontologists can determine how old ______________ are.
• They use _____________________dating to determine the half-life of the fossil.
Theory of Evolution
Day 2
Biological Molecules Provide Evidence
• Proteins
• Amino acids are building blocks of _____________
• Amino acid + Amino acid + Amino acid = _____________
• The more amino acids two species have in
_______________, the more closely __________
they are.
• Nucleic Acids
• Scientists can determine the number of nucleotide differences among organisms to see how
closely related they are.
• They make _______ comparisons.
Anatomy and Development Suggest Common Ancestry
• Vestigial structures
• __________________ structures
• Development of __________________
VESTIGIAL STRUCTURES: Structures that are present in an organism
but are reduced in size or are no longer
_______________.
*EXAMPLES: Wings of _________________ birds, fingernails on manatee fins, and
________________________ in humans (not a structure but is a vestigial reaction).
HOMOLOGOUS STRUCTURES: Structures that are ____________ in
form but are ________________ in
function.
EXAMPLES: Forelimbs of vertebrates.