Well, Musti you would be surprised, if you studied the history of ancient science, especially when we consider how much the ancient community, also in Arabia was influenced by the Greek, Hellenistic culture, philosophy and science.
Sadly, we are seriously mistaken if we consider the ancient community to be shortminded and ignorant, as a matter of fact, few modern scientists even realise how closely the ancient science resembles the modern.
In case of embryology, there were (if I remember correctly) ten embryology schools scattered over Syria and Arabia prior the time of Muhammad; the studies in these schools elaborated on the embryological predictions made by Aristotles and other ancient scientists, which resembled closesly the Koranic idea on embryology.
So Musti, whether Muhammad plagiarized previous scientific predictions or not, the fact remains, such predictions need not to be revealed by Allah, as a matter of fact Lucretius (1 century BC) was an atheist.
However, it seems obvious that the idea that the moon reflects sun light was a commonly spread idea across the ancient world.
Thus this idea gives not miracolous credit to the Koran.