Until recently, not much was known about the relationships between predator and prey in the vastness of the deep-sea food web.
So what did scientists do? For years they did the same old same old: studying the dissected guts and stomach contents of the unfortunate deep-sea creatures they happened to pull up in nets.
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Fast forward. Enter technology. Enter the underwater robots.
A new comprehensive field survey by the Monterey Bay Aquarium Research Institute reviewed 30 years of video footage from remotely operated underwater vehicles (ROVs). The study has revealed information about "who is eating whom underwater."
Yay! You know you wanted to know! But was your money on jellies?
Scientists were surprised. After watching "almost 750 different video observations of animals eating one another" (this is so not Netflix and chill), the MBARI researchers noted that far from being gelatinous good-for-nuthin' food web "dead ends," jellies were really predatory.
Like, super predatory.
It was suspected that the deep-sea food web would be very complex and very active. Down there in the deeps, food is hard to come by. There is fierce competition for the eats. To eat is to win.
It was found that one dinner-plate sized jelly freakishly could eat 22 other species of animals.
Jellies are critical to deep-sea food webs, and we've been totally underestimating these translucent, spineless, preschool-lunch Jell-O-like blobs.
The MBARI scientists even found a helmet jelly (Periphylla periphylla) double-dipping at the deep-sea snack bar, eating a squid and a little medusa.
Forget octopuses' onward-to-human-glory meme; this whole time it's been the jellies like Stygiomedusa gigantea who are the GOAT, giant guardians of the underworld food web.
Watch more footage of these gelatinous predators below.