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Why amphibian bulldozers are called "bulldozers" even though they scoop mud and soil ?
Amphibian bulldozers have a cover on the blade to prevent the soil from leaking into the water; they scoop and carry mud to the ground. Nevertheless, their main role is to push the mud, and even the ground under the water. Therefore, they are categorized as bulldozers.

Bulldozer which can be used in water (D155W)