In a group of arthropods called radiodonts:
The many species share a similar body layout comprising of a head with a pair of large, segmented appendages for capturing prey, a circular mouth with serrated teeth, and a squid-like body. It now seems likely that some lived at depths down to 1000 metres and had developed large, complex eyes to compensate for the lack of light in this extreme environment.
“When complex visual systems arose, animals could better sense their surroundings,” Professor Paterson explained. “That may have fuelled an evolutionary arms race between predators and prey. Once established, vision became a driving force in evolution and helped shape the biodiversity and ecological interactions we see today.” …
“The predator has the eyes attached to the head on stalks but the filter feeder has them at the surface of the head. The more we learn about these animals the more diverse their body plan and ecology is turning out to be,” Dr Edgecombe said.
“The new samples also show how the eyes changed as the animal grew. The lenses formed at the margin of the eyes, growing bigger and increasing in numbers in large specimens — just as in many living arthropods. The way compound eyes grow has been consistent for more than 500 million years.”University of Adelaide, “Incredible vision in ancient marine creatures drove an evolutionary arms race” at ScienceDaily
Paper. (open access)
Okay, but wait. Just because it would benefit a life form to have sophisticated eyes does not mean that it can just start growing them. That’s where Darwinism begins to shade into magic. There’s a missing factor here: How, exactly, were the prey life forms enabled to participate in the complex business of producing vision in response to the predator’s vision?
By the way, if arthropod eyes grow in a way that has been “consistent” for 500 million years, that’s an example of stasis.
See also: Stasis: Life goes on but evolution does not happen