String figure glossary

Cladogram (Evolutionary Tree)

string figure Invented by Martin Probert 2003. Construction time: 25 seconds.

This cladogram might illustrate how fish, reptiles, monkeys, apes and man are grouped in relation to the possession of four limbs, fur, taillessness and bipedalism. The lowest branching point would then divide the fish (at the end of the short branch) from the species with four limbs (reptiles, monkeys, apes and man). And similarly for the other branching points.

  1. Use a loop at least five foot, or 1m 50cm, wide.
  2. Hold the left hand palm down.
Constructing the uppermost branching point:
  1. Hang the loop on the left thumb. Press the thumb against the index to prevent the string slipping.
  2. There are two hanging strings, a near string and a far string. With the right hand take hold of a point on the far string about 4 inches (10 cm) below the left thumb.
  3. Raise the right hand and hang the string over the left index. Press the left index lightly against the left middle finger to prevent the string slipping.
  4. Release the right hand. The string forms an M-shape consisting of the near hanging string, a small central hanging loop, and the far hanging string. The bottom of the central loop should lie about 2 inches (5 cm) below the left hand.
  5. Keep the left hand palm down and point the left thumb to your right.
  6. Pass the right thumb and index from right to left through the hanging loop, take hold of the near hanging string and pull it to the right through the hanging loop.
  7. Keep pulling the right hand loop until the distance from the right hand to the bottom of the central hanging loop of the M is equal to the distance of left hand from the bottom of the central hanging loop of the M.
  8. Place the right hand loop on the left index. Don't let this loop slip during the next step.
  9. Navaho the two loops on the left index. The uppermost branching point of the cladogram appears. The branching point should lie about 2 inches (5 cm) below the left hand. Adjust if necessary.
Constructing the second branching point:
  1. Two strings hang down from the branching point just constructed. With the right hand take hold of a point on one of the strings about 6 inches (15 cm) below the branching point.
  2. Raise the right hand and hang the string over the left middle finger. Press the left middle finger lightly against the left ring finger to prevent the string slipping.
  3. Release the right hand. The string again forms an M-shape consisting of the near hanging string, a central hanging loop, and the far hanging string. The bottom of the central hanging loop of the M should lie about 2 inches (5 cm) below the branching point.
  4. Repeat steps 7 to 9.
  5. Place the right hand loop on the left middle finger. Don't let this loop slip during the next step.
  6. Navaho the two loops on the left middle finger. Another branching point of the cladogram appears. The two branching points should lie about 2 inches (5 cm) apart. Adjust if necessary.
Constructing the third branching point:
  1. Two strings hang down from the lowest branching point. With the right hand take hold of a point on either string about 10 inches (25 cm) below the branching point.
  2. Raise the right hand and hang the string over the left little (not ring) finger. Press the left little finger lightly against the left ring finger to prevent the string slipping.
  3. Release the right hand. The string again forms an M-shape consisting of the near hanging string, a central hanging loop, and the far hanging string. The bottom of the central hanging loop of the M should lie about 2 inches (5 cm) below the branching point above it.
  4. Repeat steps 7 to 9.
  5. Place the right hand loop on the left little finger. Don't let this loop slip during the next step.
  6. Navaho the two loops on the left little finger. Another branching point of the cladogram appears. All branching points should lie about 2 inches (5 cm) apart. Adjust if necessary.
Constructing the lowermost branching point:
  1. Two strings hang down from the branching point just constructed. With the right hand take hold of a point on either string about 14 inches (35 cm) below the branching point.
  2. Raise the right hand and hang the string over the left ring (not little) finger. Press the left little finger lightly against the middle finger to prevent the string slipping.
  3. Release the right hand. The string again forms an M-shape consisting of the near hanging string, a central hanging loop, and the far hanging string. The bottom of the central hanging loop of the M should lie about 2 inches (5 cm) below the branching point above it.
  4. Repeat steps 7 to 9.
  5. Place the right hand loop on the left ring finger. Don't let this loop slip during the next step.
  6. Navaho the two loops on the left ring finger. The final branching point of the cladogram appears. The final branching point should lie about 2 inches (5 cm) below the point above it. Adjust if necessary.
Displaying the cladogram:
  1. Place the foot, or other firm object, into the loop at the base of the cladogram.
  2. Transfer the left ring finger loop to the right little finger.
  3. Transfer the left little finger loop to the right ring finger. Omit this step for a less formal (less wind-swept) looking tree.
  4. Transfer the left middle finger loop to the right index.
  5. Transfer the left index loop to the right thumb.
  6. This is the cladogram.
  7. To dissolve the figure, release all loops except the left thumb loop and the foot loop.

See also the footnote to Spinal Vertebrae.

Copyright © Martin Probert 2003
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