Rideau Canal - Fixing A 425-Million-Year-Old Misnomer
An encounter with one of my favourite Ontario critters on Murphy's Point kickstarts a winding road through nomenclature that takes us 425 million years into the past and back by way of Scotland and Australia.
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In August of 2020, without pretty much any fanfare, a 425 million year old misnomer was finally resolved.
Our third campsite on the Rideau was here on the south side of Murphy’s Point. And it was there I found one of my personal favourite Ontario critters - narceus americanus, also known as the American Giant Millipede, Worm Millipede, or best of all, The Iron Worm.
They’re benign, beautiful creatures with maroon and greyish-mauve segments and deep red legs. And as one of their names suggests, they’re big for an Ontario bug - up to four inches long.
Millipedes have been around approximately forever - at least 425 million years, making them among the first land animals, and the first that we have fossil evidence of, courtesy of the island of Kerrera in Scotland.
They’re also an example of an important early evolutionary phenomenon called Metamerization - building a sequence of identical body segments. Our backbones are built on exactly the same principle as the millipede’s many segments… that give them their name.
Along with centipedes, they’re from the subphylum ‘myriapoda’ which means ‘many feet’.
But both ‘millipede’ and ‘centipede’ are technically misnomers.
Centipedes - meaning ‘hundred foot’ - literally cannot have exactly one hundred feet, their legs always grow in odd-numbered pairs.
And in about 12,000 worldwide species of millipede - meaning ‘thousand foot’ - not a single one has had a thousand or more feet. That is, until quite recently - in August of 2020.
During an environmental impact survey for a proposed mine in Australia, leaf litter traps 60 meters down brought up this lanky little guy - Eumilipes persephone, a new species with a whopping 1306 legs. The first millipede we’ve ever found to make it past that thousand-foot threshold. It got that ‘e-u’ at the start of its name as a badge of honour. It means ‘true’ thousand foot.
So, after 425 million years of millipedes, we have finally found one that lives up to its name.