(1) This description helps to explain why both the dugong and the manatee have given rise to tales about mermaids, marine creatures with breasts and a forked tail.(2) Like its relative the manatee, the dugong 's numbers are declining, with hunting, oil pollution, land reclamation and other human activities the causes.(3) A modern analog for this is the dugong from the Pacific Ocean.(4) Dugongs and manatees make up the order Sirenia, so-named because dugongs and manatees are thought to have given rise to the myth of the mermaids or sirens of the sea.(5) Genetic evidence suggests that the elephant's closest relatives in evolutionary terms are manatees and dugongs , herbivorous sea cows that live full-time in the water.