When a dead whale accidentally gets washed up on the beach, it begins to decompose as it is not eaten up by sharks or other fishes. During decomposition, various gases like methane and carbon dioxide are produced within its body.
But since there is a thick layer of blubber under tha skin of whales, the gases cannot escape out. This, they begin to build up inside the whale’s body, causing it to bloat.
Now, such gases are also produced in other animals after their death. But since the body of whale is large, it produces more gases, thus increasing the pressure in its body.
Eventually, due to the increased pressure, the accumulated gases, tissues, flesh, etc. Forcefully come out through weak spots, thus creating an explosion.
Hence, it is always advised to not stand or sit on a dead whale because it might lead to increased pressure at weak spots, thus causing on explosion.
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