Name ___________________________________
Darwin’s Natural Selection Worksheet
Read the following situations below and identify the 5 points of Darwin’s natural selection.
1) There are 2 types of worms: worms that eat at night (nocturnal) and worms that eat during the day (diurnal).
The birds eat during the day and seem to be eating ONLY the diurnal worms. The nocturnal worms are in their
burrows during this time. Each spring when the worms reproduce, they have about 500 babies but only 100 of
these 500 ever become old enough to reproduce.
a. What type will survive natural selection? _______________________________
b. Which type wont survive natural selection?_______________________________
c. What are the two variations in this population?
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d. Which variation is favorable?
_________________________________________________________________________
e. How does this example show that more offspring are produced that survive?
_________________________________________________________________________
f. What will happen to the populations over time?
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2) There are 3 types of polar bears: ones with thick coats, ones with thin coats and ones with medium coats. It is
fall, soon to be winter. The temperatures are dropping rapidly and the bears must be kept warm, or they will
freeze to death. Many of the bears have had 3 cubs each but due to the extreme temperatures, many mothers
only have one cub left.
a. What type will survive natural selection? ______________________________
b. Which type wont survive natural selection?____________________________
c. What are the two variations in this population?
_________________________________________________________________________
d. Which variation is favorable?
_________________________________________________________________________
e. How does this example show that more offspring are produced that survive?
_________________________________________________________________________
f. What will happen to the populations over time?
_________________________________________________________________________
