My cats love dichotomous keys too

Toy (Zab.) plaything

An item designed and manufactured for use in play.  Made from numerous materials, including rocks, sticks, clay, fibers, metals, plastics, and others.  Recently, many toys have included electronic components to enhance the play experience.   Some engineers also use them to make design mock-ups.

A. Toys made from cloth and fibers.

B. Round

C. Pink material with iridescent sparkles ……………………………………….. 1) Pink cat ball

C’. Black and white with pink dots ……………………………………………. 2) Striped cat ball

B’.  Not round

D. Mouse-shaped

E. Big, white body …………………………………………………… 3) Big mouse cat toy

E’. Small, white body w/black spots ………………………… 4) Small mouse cat toy

D’. Not mouse-shaped

F. Shaped like Piglet™ from Disney’s “Winnie-the-Pooh” …….. 5) Piglet™ cat toy

A’. Toys made from plastic.

G. Round

H. Blue, with a small silver bell inside …………………………………. 6) Blue plastic cat ball

H’. Black and white, with a small silver bell inside …………………. 7) B&W plastic cat ball

G’.  Not round

J. Rectangular

K. 6-8 pegs

L. 6 pegs, in two linear rows of 3

M. Green………………………… 8) Green 6-pegged building block

M’. Red……………………………… 9) Red 6-pegged building block

L’. 8 pegs, in two linear rows of 4

N. Blue……………………………. 10) Blue 8-pegged building block

N’. Red…………………………….. 11) Red 8-pegged building block

K’. 2-4 pegs

O. 2 linear pegs, in one linear row

P. Yellow ……………… 12) Yellow linear 2-pegged building block

P’. Red ……………………. 13) Red linear 2-pegged building block

O’. 4 linear pegs, in one linear row

Q. Green ………………. 14) Green linear 4-pegged building block

Q’. Blue ………………….. 15) Blue linear 4-pegged building block

J’. Square

R. 1 pegs

S. Green or Blue

T. Green ……………… 16) Green square 1-pegged building block

T’. Blue …………………. 17) Blue square 1-pegged building block

S’. Gray or Red

U. Gray ………………… 18) Gray square 1-pegged building block

U’. Red ………………….. 19) Red square 1-pegged building block

R’. 4 pegs, in two linear rows of 2

V. Green ……………………….. 20) Green square 4-pegged building block

V’. Gray …………………………… 21) Gray square 4-pegged building block

There is a potential variation for J and J’:  the building blocks could have been sorted by single pegs, then organized by linear rows [broken down as one linear row (of 2 and 4 pegs) and two linear rows (of 2, 3 and 4 pegs)].  However, organizing by Rectangular and Square led to a simpler, more straight-forward classification.

No distinction was made between dark gray and light gray building blocks.  This, too, could be broken down further.