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“zygodactyly”
An arrangement of digits in birds, with two toes facing forward (digits two and three) and two back (digits one and four): Zygodactyly is most common in arboreal species, particularly those that climb tree trunks or clamber through foliage.
Zygodactyly occurs with woodpeckers, flickers, nuthatches, and parrots.
This entry is located in the following units:
dactylo-, dactyl-, dactylio-, -dactyl, -dactyla, -dactylia, -dactylic, -dactylism, -dactyloid, -dactylous, -dactyly
(page 12)
zygo-, zyg-, -zygous; zygomatico- +
(page 3)