Chapter 15-16 Note-Taking Guide
Evolution: Evidence and Theory and Speciation
What is evolution by natural selection?
Evidence for Evolution
The Fossil Record
A fossil is a ______________________________.
Fossils are often found in layers of ______________________________________.
Sedimentary rock is formed when ______________________________ like dust, sand or
mud is deposited and turns to _________________________ over many years.
A _______________________________ is an imprint in rock in the shape of an
A _________________________ is when a mold fills in with hard
Sometimes a fossil can form when a whole animal is preserved in
What can Fossils Tell Us?
Law of Superposition states that successive layers of rock or soil were deposited
The lowest layer is the _____________________________because it was deposited
Any ____________________________________ found in those layers would be around
the same age as the layers.
______________________________________ is not exact but can only determine if a
fossil is older or younger than another fossil.
___________________________________________is determined using chemical
processes which can show a number of years for the age of the fossil or rock layer.
Succession of Forms
___________________________ indicate that species of organisms appeared, existed
for a while and then _________________________________ or became
__________________________________________ occur when large amounts of
Mass extinctions can be caused by the ______________________________ like volcanic
activity or from asteroid impacts.
Current extinctions are being caused by ______________________________.
____________________________________________ is the study of the comparison of
fossils to living organisms.
Biogeography shows that new organisms arise in areas where
______________________________ forms once lived.
Theories of Evolution (Change)
French scientist Jean Baptiste de Lamarck formed some of the first theories of change by
observing animals with webbed feet and other animals like giraffes.
He thought that ____________________________________________ like ones that are
earned through life were passed down to offspring.
His idea was easily __________________________________ but Lamarck was one of
the first thinkers of change of his time.
Darwin’s Dangerous Idea
In the mid-1800’s, Charles Darwin and Alfred Wallace independently developed an idea
that species were _____________________________ by
In the process of natural selection, organisms best __________________________ to
their _______________________________ reproduced more successfully than other
Over generations, the ____________________________ increase in the population.
Voyage of the Beagle
Darwin rode aboard the ship the H.M.S Beagle as the ship’s
_________________________________ so he could learn about all the plants and
animals he found.
Darwin based some of his work on the research of ____________________________
who said that many of the Earth’s geologic processes took a long time to complete and
the Earth must be quite ____________________________.
Darwin observed high in the Andes Mountains of South America that fossils of
____________________ creatures were present. How did they get up there?
Darwin reasoned that they ______________________________ must have been
uplifted from the sea bed many years ago.
If the land can change why not the living creatures there?
Darwin collected many _____________________________ and observed thousands of
species on his 5 year journey.
The Galapagos Islands
Darwin visited the _____________________________________________, an isolated
part of South America.
There he observed many animals ________________________ those found on the
mainland of South America.
Each island in the Galapagos had unique animals found nowhere else. Why?
that newer forms appearing in the fossil record are actually the
_______________________________ or slightly changed
_____________________________ of older species.
______________________________________________________________ states that
the __________________________________ may affect individual organisms in
different ways because they are not _________________________
_______________________________________ said populations are limited by adverse
conditions like ____________________,______________________,
and_________________________________ otherwise they would grow unchecked.
Darwin used Malthus’ ideas in his work.
A population of organisms _____________________________________ to their
environment as their proportion of ______________________________ for favorable
A single organism’s genetic contribution to the next generation is termed
A ________________________________ gives an organism an
_________________________ occur in species which can create favorable or
unfavorable traits in certain environments.
Homologous and Analogous Structures
A _____________________________________ structure is a similar feature that
originated in a ________________________________________.
These structures originate from the same areas in ____________________________of
_______________________________________ are features that look similar because
they are used for a _____________________________________ but arise from a
different embryological development like _______________________________ in birds
_________________________________________________ are features that are no
longer _______________________________________ and have no apparent function
in a current animal but had a function in a common ancestor.
Vestigial structures indicate ___________________________________.
Some animals like humans are born with vestigial structures showing like tails.
Whales have 4-chambered stomachs like a cow even though it is not used.
Examples of vestigial structures
Embryology is the study of _________________________ and their
Animals have similar _____________________________ at certain stages of
development indicating a common _________________________.
Macromolecules and DNA
All life on this planet has the same __________________________ bases and the same
types of _____________________.
This indicates that we are all __________________________.
Comparing genes and DNA, comparing amino acids sequences and comparing certain
protein sequences all lead to the same conclusion…
As the number of differences _____________________________, the more related the
two animals are.
Evolution in Action
Anyone can see evolution in action every day.
Entire ___________________________ can evolve into new species.
Larger animals take more time while bacteria and viruses can evolve in a matter of
Examples of Evolution in Action
Patterns of Evolution
__________________________________ is when two species change together in close
Some species cannot live without the other because they are so closely connected.
________________________________________evolution is when the environment
selects certain _____________________________ to be similar even though the two
animals may not closely related;
_____________________________________ evolution is when two or more related
populations over time become more _____________________________. This usually
results in a new species; dogs and wolves.
______________________________ evolution is also called
_____________________________________________, when the animals adapt to a
specific _________________________________and change into new species over time.
________________________________ is when humans select the traits and cause the
Examples of Coevolution
Many ___________________________ have _____________________ counterparts on
The ___________________________ selects an animal to occupy a habitat.
Examples of convergent evolution
What is a species?
A species is a group of animals that can ____________________________ with each
other and produce offspring that that also _________________________.
One species cannot breed with another and create offspring that can also breed.
There are many ______________________________ that can restrict breeding which
can contribute to the formation of a new _________________________.
___________________________ is the formation of a new
Isolating Mechanisms that cause Speciation
Geographic isolation is the
Reproductive isolation creates a barrier to
What do you think is the strongest piece of evidence presented?
What three people influenced Darwin’s work?
How can we see evolution working today?
How are new species being created?