Download Evolution in the Living Environment

“Do Now”
• Take out a sheet of paper and answer the
following:
– What are 3 things that come to mind when
you think of the word “evolution”? Be able to
explain your response.
Evolution
The process of change over time
In this unit we’ll discuss…
•Evidence of evolution
•Theories of evolution
•The Heterotroph Hypothesis
•Natural selection
•Modern evolutionary theory
Evolution Defined
• The process of change over time
Evidence that Supports
Evolution
•
•
•
•
•
Geologic Record
Comparative Anatomy
Embryology
Cytology
Biochemistry
Geologic Record
History in Rocks
• Rocks provide clues to the past through
fossils
• About 95% of the species found in ancient
fossils are now extinct
Formation of Fossils
The remains or traces of organisms
Fossils
• Relative Dating
– Looking at layers of rocks to
determine the age of a fossil
• Doesn’t determine exact age of
fossil
• Absolute Dating (Radioactive)
(Radiometric)
– Using C14 to determine the
age of a fossil.
• Shows exact age by looking at
radioactive chemicals in the
fossil
History in Rocks
• Types of fossils include:
– Trace fossils
– Casts
– Molds
– Petrified / Permineralized fossils
– Amber-preserved / Frozen fossils
Fossils
• Amber – plant resin (tree
sap) that contains tissues of
an organism
• Petrification – tissues of an
organism are replaced by
minerals (turn to stone)
• Imprints, casts, molds –
found in sedimentary rock
• Sedimentary rock – layered
rock
– Strata – layers
– Oldest layers on bottom
– Extinction can be easily
seen in sedimentary rock
What can you infer about this
habitat based on this picture?
Studying Evolution
• Comparative Anatomy
– Comparing structures of organisms
Have similar bone structures,
but different functions.
Analogous Structures
• Have similar functions, but different
structures
– Example – bird and butterfly wings
Structures
that exist, but
are no longer
used in an
organism.
Studying Evolution
• Embryology
– Comparing embryonic
structures
Studying Evolution
• Cytology
– Comparing cell
structures
Studying Evolution
• Biochemistry
– Comparing chemical makeup
Evidence of Evolution
End of Day 1