Download File - IB Psychology Mr Poll

Evolution
A Theory of Charles Darwin
In 1831 ________________ set sail with a crew of 73 men from England with a goal of sailing the world.
Early Ideas about Change
In the ____ and ___ hundreds scientists recognized that living things change over ______. This is broadly
described as the process of __________. Most thought that traits developed or acquired by an organism
during its lifetime are passed on during its __________.
Giraffes during its lifetime stretch its necks to reach ________ on trees. The Giraffes neck would grow
longer as it grew ________. The giraffe would pass on the ________ of a longer neck to its offspring.
Journey of the HMS Beagle
The trip originally planned for __ years turned into a __ year journey around the world. ________ saw a
wide variety of plants and animals and collected hundreds of ___________ to bring back to England.
Darwin began to think that perhaps _______ ________ also change slowly over long periods of time.
Theory of Evolution
Darwin felt that changes in earth’s ________ over long periods of time also influenced ________ and
_________ life.
This information suggested that the __ different types of _______ on the Galapagos Islands descended
from a ________ species of finch that originated on South America.
Over the next 20 years Darwin flushed out what he called the theory of _________ __________.
The Theory of Natural selection
From 1836 to 1859 Darwin ________ a great deal about his journey. In 1859 Darwin published the book
that changed the field of biology. The Origin of _______ by Means of Natural Selection. Darwin’s work laid
the foundation of our modern __________ understanding of evolution. Evolution is the ________ of
________ over a long period of time.
_________ __________ occurs when individual traits within a species survive because they are best
_________ to their environment and ______ these variable traits on to their offspring. For example
_________, _________, and __________. It’s the environment or nature which is the driving _______
influencing the selection of those surviving ___________.
Competition and Natural Selection
______________ of offspring often result in competition. If food is scarce individuals are forced to
_________ for food. Individuals who are successful ___________ are more likely to survive passing on the
traits that made them successful.
Adaptation and Natural Selection
Some _________ may be more helpful than others. ___________ is a variation that makes an organism
better suited to its environment.
The key to Darwin’s theory of evolution is the principal of _________ or as Darwin calls it natural
___________. Darwin proposed that individual organism with an adaptation which gives them an
_____________ is more likely to survive and ____________.
Perhaps you’ve heard the phrase “________ __ ___ _________.” This phrase sums up the idea that those
individuals with helpful ___________ will survive and reproduce.
Speciation
The factors of ____________, competition and adaption are the components for natural selection to occur
and over time can result in the formation of an entirely _____ _________. One of the most important
factors promoting speciation is ____________.