Alright, yes – the title of this post does pose the weirdest question ever asked on this blog, so I’ll tell you all how I came round to this hypothesis…
It started as a comment on a blog post about films, asking how The Little Mermaid would reproduce… it was a pretty random question; but one that got me thinking…
You see, if a mermaid has a human top then it would be likely that she would produce milk for her young – technically making her a mammal. On the other hand (or half, you could say), mermaids have fishy tails. This suggests that instead of giving birth to live young, they may lay eggs.
A mammal that lays eggs and lives in water? Sounds like… a platypus!
The platypus is a monotreme.
“The only surviving examples of monotremes are all indigenous to Australia and New Guinea, although there is evidence that they were once more widespread. Among living mammals they include the platypus and four species of echidnas (or spiny anteaters).” – Wikipedia
So, essentially my theory is that a mermaid could also be a type of monotreme; laying eggs and then looking after the young when they hatch… The eggs would have to be laid on land, as platypus eggs are – they would simply drown if they were laid under water. Perhaps there are caves with mermaid nests in. That’s a pretty cool thought!
Of course, this is glossing over the whole ‘ do mermaids breathe underwater?’ issue… If they are able to breathe underwater they must have gills, which means that they would not be mammals at all; gills simply cannot provide enough oxygen from the water to sustain a mammal.
“Cold blooded animals need a lot less oxygen than warm blooded animals do. Imagine that you have a 100-pound human and a 100-pound fish sitting on a couch. A human being needs maybe 15 times more oxygen than the fish does. If the human then gets off the couch and starts swimming, the human needs even more oxygen. So does the fish, but fish are super-efficient in the water… Compared to air, there just is not enough oxygen dissolved in water to keep a warm-blooded animal going.“ – How Stuff Works Express
In most myths of mermaids, they are often seen on rocks – so gills would seem unlikely as they cannot function properly out of the water. This, along with the fact that images of female mermaids pretty much always includes mammary glands (hee hee – boobs! Sorry, couldn’t resist!), seems to suggest that actually the species would be classed as a mammal and thus would have to surface to breathe like a seal or a dolphin.
So there you have it: my theory that mermaids are actually a type of monotreme mammal; living in the water but having to surface to breathe, laying eggs on land and then feeding the young on milk until they can swim and fend for themselves.
I think it’s a good theory. If only mermaids actually existed…