In the Holy Quran, God speaks about the stages of man's embryonic development:
{We created man from an extract of clay. Then We made him as a drop in a place of settlement, firmly fixed. Then We made the drop into an alaqah (leech, suspended thing, and blood clot), then We made the alaqah into a mudghah (chewed substance)... }(Quran, 23:12-14)
Literally, the Arabic word alaqah has three meanings: leech, suspended thing, and blood clot.
In comparing a leech to an embryo in the alaqah stage, we find similarity between the two as we can see in picture 1. Also, the embryo at this stage obtains nourishment from the blood of the mother, similar to the leech, which feeds on the blood of others.
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