Are mermaids/mermans real?What is the truth.Do they really exist?

They are known worldwide.When technology started evolving people started sailing the seas,and about 30,000 years ago they found a cave where painting of mermaids and mermens were drawn.In different religions and cultures they are described in a different way.In some cultures mermaids and mermens are said to be handsome,,beautiful,half body human like up to waist and down the waist look like fish with a fishy tail.And in some cultures they are said to be ugly,have large teeths,green in colour,pig like eyes and a red nose.But the similarity in there religions is that they are said to be immortal and are legendary creatures,or you can say god like creatures possessing magical powers.

Why only mermaids are well known and mermens are less popular? What if aren't immortal.How do they reproduce? How does there digestive system works? No one have the answer to this questions.And if they have half human like body then how do they survive in such a cold place like oceans.

So if they exists they have to be immortal to survive.According to me they exists because if they dont exist then why they are popular worldwide,how their paintings are drawn in those ancient caves.So they are like gods.If you believe they exists and if you dont believe then they dont exists.That depends on you because until now nobody has provide a solid proof for mermaids and mermen.