Ostriches don’t bury their heads in the sand to hide or for anything else for that matter. It’s a myth than can be traced to Pliny the Elder (23-79AD) the author of Naturalis Historia, which is an attempt to cover all the knowledge to be found in the Roman Empire. In Book 10, Chapter 1, Pliny says “(Ostriches) imagine, when they have thrust their head and neck into a bush, that the whole of their body is concealed”.
The knowledge to be found in the Roman Empire was not always right, but who are we to throw stones?