For decades, a tiny crustacean was believed to be a recent invader of Canada, but it arrived more than 350 years ago.

A recent scientific study indicates that the spiny water flea, a tiny crustacean previously thought to be a recent invasive species in Canada, likely arrived in North America over 350 years ago. Researchers reached this conclusion after analyzing sediment samples collected from Three Mile Lake in Muskoka, Ontario.

The findings suggest that the organism may have reached the region through natural processes centuries earlier than previously estimated. This discovery challenges long-standing assumptions regarding the timeline and introduction of the species in the Canadian ecosystem.