Complex sentence: Biologists have observed that the sharks usually swallow their prey whole, which if the prey is too large can lead to health problems for the shark such as esophagus, heart, and liver damage.
Split into simpler sentences: Biologists have observed that the sharks usually swallow their prey whole. If prey is too large, swallowing it whole can lead to health problems for the shark such as esophagus, heart, and liver damage.