Name:
Per:
Homologous Structures
Use the color key below to color each human bone a different color. Then color all the
homologous structures in the animal bones and identify each limb's name and functions
humerus- red
radius- green
ulna- blue
carpals- yellow
metacarpalsbrown
phalangesorange
Name of Limb:
Arm
Function: lifting, carrying, writing
Name of Limb:
Name of Limb:
Function:
Function:
Name of Limb:
Name of Limb:
Name of Limb:
Function:
Function:
Function:
Homologous structures
1. Look at the hands of the 4 animals above. Explain what might have made these structures so similar.
2. What do the heavy lines below the pictures indicate?
3. What does the line the arrow is pointing to indicate?
Analogous Structures
Examine the wings of a bat (mammal), bird and fly (insect).
4. What functions do these structures share?
5. How do the structures differ?
6. What similar environmental pressures might have led these animals to have wings?
7. Is it likely these organisms had a common ancestor?
Vestigial Structures
Gradual changes have occurred through time that in some cases reduced or removed the function of some body
structures and organs.
Cave fish
Minnow
The cave fish and minnow above are related but the cave fish is blind.
8. Explain why eyesight is not an important adaptation to life in a cave.
9. Why does the appearance of the cave fish and the minnow suggest a common ancestor?
10. The picture to the left shows the hip bone (pelvis) and thigh bone (femur) of a whale. Whales do not walk. Why do
they have these bones?
Complete the table of human vestigial structures below.
Structure
Coccyx (tail bone)
Muscles that move the ears
Muscles that make your hair stand up
Little toe
Wisdom teeth
Probable function
Why did it become vestigial?