Activity

Opposable thumbs

Summary
Try on gloves that have two or three fingers sewn down, to appreciate how an opposable thumb helps with manipulation.
Science content
Biology: Features, Adaptations of Living Things (K, 1, 3, 7)
Lessons activity is in
Materials
  • three or four gloves with different fingers sewn down (see photo)
  • marbles or other small objects to pick up
Procedure

Students choose a glove and fold down their fingers, the same ones as the glove, then put their hand into the glove.
With the fingers that remain outstretched, try and pick up a marble. (Make sure that younger students do not use their fingers curled inside the glove to help manipulate.)
Which gloves are easiest to use and which the hardest?

Discussion: usually it is easier to pick up objects when the thumb is involved. The thumb sticks out in another direction from the fingers (it is opposable), so grabs the object from another side, helping pick it up.

Other animals with opposable digits:
Some other animals have opposable digits on their feet and are also dextrous: gorilla, chimp (and other great apes), baboons (and other Old World Monkeys) gibbons, giant pandas and opossums.
Birds also have one digit facing backwards on their feet, making them good at gripping branches.

Raccoons do not have opposable thumbs, but are able to fold their fingers down into their palms, which helps them with dexterity.

Notes

Ks were not able to only use the fingers that were outstretched. Try with older grades.

Grades taught
Gr K
Gr 1
Gr 2