The deep sea teems with life. But in the black depths, these organisms remain largely mysterious.

Squids in the deep ocean are rarely observed alive, but scientists on an exploration mission used a deep-sea robot to capture footage of a squid clutching a brood of unusually large eggs — twice the size of typical squid eggs. The new research, aptly titled "Giant eggs in a deep-sea squid," concludes it's an unknown species.

"Our unexpected encounter with a squid brooding giant eggs caught the attention of everyone in the ship’s control room," Steven Haddock, a senior scientist at the Monterey Bay Aquarium Research Institute and an author of the new research, said in a statement. "This remarkable sighting underscores the diversity of ways that animals adapt to the unique challenges of living in the deep."

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SEE ALSO:Giant squid footage shows they're not terrible monsters, after all

The eggs you see in the footage below, numbering 30 to 40, are about half an inch across. That's much bigger than most fish and squid eggs, and why biologists called them relatively "giant." Often, related Gonatus squids brood up to 3,000 eggs at a time, explained the Monterey Bay Aquarium Research Institute, which uses remote controlled vehicles (ROVs) to explore the deep sea. In ocean regions with lots of predators or limited nutrients, unleashing hundreds or thousands of offspring boosts the odds of a few survivors.

But it makes sense for some species to carry large eggs. "Giant eggs may be more beneficial in the more stable and predictable conditions found in the deep sea, allowing for higher investment in fewer offspring that have a better chance of survival," the institute wrote.

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A view of the unusually large eggs seen in the squid species swimming in the Gulf of California.Credit: MBARI

The above footage is from 2015, but the biologists just completed a meticulous review of deep-sea squid ROV footage from different expeditions in an attempt to identify the species. The creature, seen at some 8,419 feet (2566 meters) below the surface in Mexico’s Gulf of California, is indeed new to science.

Aboard a small number of high-tech research vessels around the globe, organizations are now vigilantly documenting and mapping the deep sea. 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.

TopicsAnimals