Friday, 3 April 2026

CAMBRIAN SUBMARINES: OPABINIA REGALIS

Meet one of the most wonderfully peculiar animals to ever grace our ancient seas. 

This five-eyed marvel swam through the Cambrian oceans some 508 million years ago, its soft body drifting above the seafloor of what is now British Columbia—preserved in exquisite detail within the famed Burgess Shale of Yoho National Park.

At first glance, Opabinia regalis feels almost mischievous in its design. I think of them as Cambrian submarines. Five stalked eyes sit atop its head like a crown of periscopes, scanning a world teeming with early life. 

Along its sides, a series of delicate lobes ripple in coordinated waves, propelling it forward with gentle, undulating grace. But it is the feeding apparatus that truly steals the show—a long, flexible proboscis ending in a tiny claw, perfectly suited for plucking soft prey from the seafloor and delivering it to its backward-facing mouth tucked beneath the head.

Yes—five eyes. And a claw-tipped trunk. Nature was experimenting, and Opabinia was one of her boldest sketches.

When Charles Doolittle Walcott first described this curious creature in 1912, it puzzled generations of paleontologists. At the time, he believed it was an anostracan branchiopod. I don't see the resemblance but I wasn't looking at a fossil mystery with his lived experience of the time.

Walcott named the species Opabinia after Opabin Peak in the Canadian Rockies. While his initial classification as a crustacean was later debated and revised by researchers like Harry Whittington in the 1970s—who identified it as a far more enigmatic "weird wonder"—Walcott's 1912 publication remains the initial scientific description of this marvelous fancy of nature.

For decades, its place on the tree of life remained uncertain, its anatomy so unlike anything alive today that it seemed almost alien. 

Thanks to the careful work of Harry Whittington and colleagues—that Opabinia was understood as part of an early branch of arthropod evolution, a relative—albeit a very strange one—of the lineage that would eventually give rise to insects, crustaceans and spiders.

Soft-bodied and delicate, Opabinia would never have fossilized under ordinary circumstances. It is only through the extraordinary preservation of the Burgess Shale—where rapid burial in fine mud and low-oxygen conditions halted decay—that we are gifted this glimpse into deep time’s more experimental chapters.

In Opabinia, we see evolution not as a straight line, but as a riot of possibilities—forms tried, tested, and sometimes abandoned with countless strange and beautiful designs flickering briefly before fading into the stone. I am truly thrilled that we got a chance to see this one as so many never had the chance to fossilize and we'll never get to know their quirky selves.