Complex sentence: In recent years, fishing for manta rays has been significantly boosted by the price of their gill rakers on the traditional Chinese Medicine market, where pseudo-medicinal virtues have been assigned to them whithout proven scientific basis and a clever marketing strategy has generated significant demand.
Split into simpler sentences: In recent years, fishing for manta rays is significantly boosted by prices of their gill rakers on the market of the traditional Chinese medicine. Pseudo-medicinal virtues assigned to them whithout proven scientific basis and a clever marketing strategy generate significant demand.