The Rhea:
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The Emu:
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The Moa (extinct 1500 CE):
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The Elephant Bird (extinct 1500 CE):
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(Elephant Bird Egg (left) compared to ostrich egg (right) compared to hand):
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The Kiwi:
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All the preceding were related to the beloved Struthio Camelus (Ostrich).
This has been your daily dose of ostrich education.