We know the ocean is 关键字1strange. Even so, it still surprises us.

Biologists aboard a University of Auckland vessel spotted a large mako shark in December 2023. But there was something orange on top of it, which they filmed and recently posted on YouTube. It's a stunning sight.

"We launched the drone, put the GoPro in the water, and saw something unforgettable: an octopus perched atop the shark’s head, clinging on with its tentacles," Rochelle Constantine, a professor in the School of Biological Sciences at the University of Auckland, wrote online.

"This 'sharktopus' was a mysterious find indeed — octopus are mostly on the seabed while short-fin mako sharks don’t favour the deep," Constantine added. (What's more, octopi are often solitary creatures.)

As you can see in the clip below, both creatures appear perfectly comfortable with the transport situation. Perhaps some sort of symbiotic relationship?

Mystifying sightings like this, however, require allowing the ocean wilderness to thrive. But sharks are having a hard time. The global abundance of sharks and rays has dropped by a whopping 71 percent over the last half-century, largely due to overfishing and by-catch. Sustaining these wilds means managing Earth's fisheries to vastly reduce the chances of shark bycatch, protecting their habitats, and cutting the amount of pollution flowing into their homes.

"The sharktopus encounter is a reminder of the wonders of the ocean," Constantine said. "One of the best things about being a marine scientist is that you never know what you might see next in the sea. By supporting conservation initiatives, we can help to ensure that such extraordinary moments keep happening."

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Biologists also underscore the importance of protecting the ocean realms we can't often observe — the dark, deep sea.

Ocean research organizations are now vigilantly documenting and mapping these depths, thousands to tens of thousands of feet underwater. Scientists want to shine a light — literally and figuratively — on what's down there. The implications of knowing are incalculable, particularly as deep sea mineral prospectors prepare to run tank-like industrial equipment across parts of the seafloor. For example, research expeditions have found that ocean life carries great potential for novel medicines. "Systematic searches for new drugs have shown that marine invertebrates produce more antibiotic, anti-cancer, and anti-inflammatory substances than any group of terrestrial organisms," notes the National Oceanic and Atmospheric Administration.

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