Terra: Platypus

Tail
Like the rest of the platypus body, the tail is covered in hair.  It's less dense than the sea otter (because they are ALL less dense than the sea otter), but is serves a similar purpose.  They have two layers of hair and a bubble of air is captured between them.  That layer air keeps the otter warm when it's maneuvering the Australian/Tasmanian waters.

Their tail isn't really used to propel the animal in swimming.  Instead, it's used as a rudder of sorts.  Even sassier, though, is that the tail is their fat reserve where they can stock up and store the goods for times when fish might be scarce.  Feed these guys a few blueberry pies, and they'll be all tail.


Feet, spurs and legs
Yeah, as you can imagine, the platypuses feet are webbed, because no other mammal's feet are.  (You'll be reading that a lot this post.)  At the end of those toes are giant claws that are used for digging and walking on land.  In a swimming technique unique to the platypus, they only use their front legs to propel themselves.  The back legs kind of tuck up next to the torso and are used, like the tail, for navigation.

Male platypuses have spurs just north of their feet.  These spurs, unlike a dog's dewclaw, is actually poisonous.  Yes.... poisonous.  It's not enough poison to kill a human, but it'll knock a fish or frog silly.  Once again, this poison is unique to the platypus, and it doesn't aim to paralyze the target, just give it insane amounts of pain.  The pain can be so overwhelming, it can incapacitate the target.  That's what I'm talking about.  Spurs!  Poisonous SPURS!  Holy.  Moly.

Another thing is the platypus walks like a reptile, not a mammal, because its legs are affixed to the side of its torso instead of beneath it.  This platypus is impossibly unique.


Torso
Again, this is covered in fur to help maintain their body temperature, which, as you'd imagine, is lower than most warm-blooded mammals.  They keep themselves at 90 degrees Fahrenheit (32 degrees Celsius), which is substantially lower than other mammals ~99F (37C).

Inside this torso, they have their reproductive organs.  They, of course, are also odd.  For example, the female has two ovaries, but only the left one functions.  The eggs it releases are similar to reptile eggs (leathery).  Oh, yeah... the platypus is unique in that it's a mammal that releases eggs instead of giving birth to living baby.  The baby platypuses break out of their eggs blind and hairless.  They feed off their mother's breast milk, but, of course, the platypus has no nipples.  (Breast milk with not breasts!  It's just so platypus!)  Instead, the female releases the milk through pores in the skin and - get this - gathers in groves in their abdomen to form pools of milk that the young lap up.  I mean... this is madness.

Another unique thing is the genetics behind this platypus.  The sex chromosomes of mammals are the simple XY we're all familiar with, but the sexual genes of the platypus are like ZZ/WZ sex chromosomes found in birds.  Holy poopers.  So, while mammals have two sex chromosomes, the platypus has ten.

Bill
Large, rubbery snout.  Unlike a bird, though, where a beak splits to reveal a mouth, the platypus' bill is a sensory organ and the mouth is actually beneath it.  That blows my mind.  Of all the things the platypus has in its repertoire of strangeness, a giant (and I mean GIANT) sensory organ that dominates the middle of the face is the hardest for me to wrap my head around.  The eyes and mouth are tucked away on the edges of the bill.

The bill is a giant organ-that-sits-in-middle-of-face for a good reason.  The thing uses freaking electrolocation, people.  It's as sassy as it sounds.  Again, it's unique to the platypuses animal group (which also includes the odd echidna.)  What the bill does is... and this sounds like a superhero skill... is that it can locate its prey by detecting slight electric fields generated by muscular contractions.  The bill is so sensitive, it can actually pinpoint the electric field, like stereo vision or stereo sound.  So, the platypus will get to the bottom of the river and start swimming by the muddy bottom.  They'll usually close their ears, nose and eyes and just use the bill to navigate.  Once it detects the electric result of muscle contraction, it would dig, pushing away the muck with its bill, then snagging the little guy in it odd.... mouth.


Mouth
Once again, the platypus has a mouth structure unlike any other mammal.  (It has something to do with the shape and how the muscles open the mouth.) 

Even more odd, though, is that only baby platypuses have teeth.  Three molars keep them eating until they leave the home to head out on their own.  Then the teeth fall out and they use keratinized pads to monch their food.  Keratinized pads?  Yeah... think... dog's paw pads, but in the mouth.  Oh, and they are carnivores, these bad boys.  They'll throw down fish, worms, shrimps and crayfish.  In fact, they need to eat 20% of their weight every day, which requires them to forage for food 12 hours a day.  That's an insane amount of time when you consider that lions sleep for 18-20 hours a day.

One final note about this mouth: they have been known to produce a low growl, which is adorable.  It's like when an ant throws its head and front legs in the air to be intimidating.


Ears and Nose
The ear opening is beneath the jaw bone... Again, the only mammal to have this.  The nose?  It's the top of the rubbery bill so they can breathe while swimming. 


The basic info:

• 1.5-5.3 pounds (0.7-2.4 kg)
• Males average 20 inches (50 cm) in legth
• Females average 17 inches (43 cm)
• They live 11 years in natural habitat and 17 in captivity