Chapter 15
Review Sheet
How do fossils form?
 Buried in sediment
 Buried on ocean floor, swamp, mud etc…
 Tissue replaced by minerals
 Trapped in tree sap
Where did Darwin collect much of his
information?
 Galapagos Islands
Darwin hypothesized that his finches
probably evolved from:
 A common ancestor
Process by which a population
becomes better suited to its
environment
 adaptation
Evolution occurs because of
 Natural selection
Organisms that are well suited for their
environment that reproduce and pass
on their traits do so by
 Natural selection
What can happen to populations of the
SAME species living in different
places?
 Change as they become adapted to the new
environment
SAME structures are called
 homologous
Example of a homologous structure
from class
 Arm bones
Human tailbone is an example of
________structure
 Vestigial ( a structure we no longer use)
Wing of a bird and the wing of and
insect are _________ structures.
 Analogous (evolve independently but have
the same function)
Accumulated differences in a
population
 Divergent evolution
When two or more species become
more adapted over time to each other’s
presence is
 coevolution
When to species develop some of the
same features even though they are
NOT closely related
 Convergent evolution
Any preserved trace of ancient life
form
 fossil
A species that has disappeared
permanently
 extinct
Short Answer
 You discover 4 new species of birds, each on
a different island. Beaks are different. How
can you explain the differences and
similarities? (2 points)
 Why is competition among individuals of the
same species so intense? (2 points)