The year was 1799. George Shaw, eminent English zoologist of the British Museum, had just received a dried and most unusual animal specimen from Australia. This creature seemed to have so many strange qualities about it – the tail of a beaver, the bill of a duck, the body of an otter – that the British scientists quickly dismissed it as a hoax. Surely, they claimed, it was just the end result of various animal body parts being sewn together, and they weren’t best pleased at being sent what they assumed was an obvious fake.
To be fair to the scientists, their scepticism wasn’t unfounded. At the time, hoax animals were being created at an alarming rate – one of the more popular fake animals was a mermaid, which people could make by sewing the top half of a monkey onto the lower half of a fish. But George Shaw thoroughly searched the specimen for any signs of stitches and, after finding none whatsoever, he was forced to admit that this creature – whatever it might be – was indeed a real animal.
Shaw gave the animal a name: Platypus anatinus. The word ‘platypus’ was derived from the Greek words platys, ‘flat, broad’ and pous, ‘feet’, which probably referred to its webbed feet; its species name, anatinus, is Latin for ‘duck-like’. (Its name was later changed from Platypus to Ornithorhynchus – ‘bird snout’ – because it turned out that the genus Platypus already belonged to a wood-boring beetle, so platypus became the animal’s common name instead.)
Mysteries of the Egg
Even though the scientists now (begrudgingly) admitted that the platypus was a real animal, it took another thirty years before they accepted it was a mammal. True, it had fur – a defining mammalian characteristic – but no one could find those all-important mammary glands (it just seemed to ooze milk from its skin) and it had a single, all-purpose rear vent, a cloaca, like that of a reptile.
Then came more news from Australia. Apparently, some small, spherical eggs had been found in a burrow beside a river bank that was lived in by a platypus. Had the platypus been responsible for laying these eggs? That was absurd, the naturalists firmly claimed; no mammals laid eggs. They speculated that another animal, perhaps a reptile, had deposited them there. The native Aborigines insisted that the eggs did indeed belong to the platypus, but the Europeans ignored them and the argument raged for nearly a century.
The debate was only solved when Scottish embryologist William Caldwell found a platypus nest and discovered not only an egg already there but that another one was on the verge of being extruded by the female. Now there could be no doubt.
We now know that the platypus sits, along with that other egg-laying mammal, the echidna, in the monotreme order (from the Greek monos, ‘single’ and trema, ‘hole’, referring to its cloaca). These creatures represent a very early lineage of mammals. One man, John Price, saw the platypus in 1880 and, clearly unimpressed, he described it as ‘helpless, deformed and monstrous.’ Admittedly, the animal has kept some of its ‘reptilian’ features – a low body temperature, a lizard-like gait and, of course, its ability to lay eggs – but that is only because it has had no need to change them. Living as they do on the once-isolated island continent of Australia, and with few other animals to compete against, the platypus has had no pressure to evolve further.
To call the platypus an ancient mammalian prototype that was later abandoned in favour of more ‘mainstream’ mammals is disparaging to the animal. It’s not so much an evolutionary freak as it is a biological rebel. And for that it should be applauded.