Dear Dr. Jeal,
Why is it that when a mammal kneels down its legs bend forwards, but when an ostrich bends down its legs bend back?
– Junior Sophs.
The question you ask is quite curious, but I don’t think you’re on the right track,
Saying “knees of a mammal bend forward, while knees of an ostrich bend back.”
But I quite see the cause of your problem, and it’s really quite simple you see,
As the bend in the leg of an ostrich is more like an ankle than knee,
The true knee of an ostrich bends forwards, and it’s quite a remarkable thing,
It’s up at the side of the body, tucked closely under the wing.
The leg is quite similar in all birds, but ostrich proportions are wrong,
As the femur is very foreshortened, while the foot is extraordinarily long.
As the leg is made largely of foot-bones, you’ll ask “What are its feet” I suppose,
I’ve an answer all ready for that one. What you think are its feet are its toes!
Author
Frank Jeal
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