I agree that history looks only at modern man, ignoring evidence which points to any previous cycles of humanity.
The giant men with animal parts is a hotly contested subject. Gods or depictions of living beings? The Sumerians describe the existence of beings from the sky who messed with the DNA of humans to create modern man. So could these strange creatures be a result of their tests leading up the subservient being they were looking for? Or are we simply looking at our ancient masters?
Without solid evidence all we can do is feel our way into this subject with an open mind.
Thanks for including your link.