Twisting and turning atop the muddy ooze, the acorn worm (class Enteropneusta) is an unassuming worm-like animal that has a surprising connection to Earth’s climate. Named for their acorn-shaped front end, enteropneusts are actually more closely related to humans than to worms. They have a rudimentary nerve cord that is similar to ours, and they breathe oxygen using structures similar to a fish's gills.

A constant rain of particles connects the ocean's surface to deep-sea communities far below. Carbon dioxide from the atmosphere mixes into the ocean at the surface. Tiny plant-like plankton transform carbon dioxide into organic material and are then eaten by larger animals. As these animals eat, poop, and die, they create a flurry of organic material known as marine snow. The sinking snow moves nutrients and carbon all the way down to the deep seafloor, where bottom-dwelling animals, like acorn worms, enjoy a bountiful feast. This cycle is known as the biological pump.

Acorn worms are connected to us through the carbon cycle. They play a significant role in the redistribution of sediment and nutrients in deep-sea communities. As they do their part to help regulate climate, we can do our part by drastically reducing our carbon dioxide emissions. The ocean is a powerful ally that has buffered us from the impacts of climate change—now it is our turn to act on climate change to safeguard the future of the ocean and its inhabitants.

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Script writer: Larissa Lemon
Science advisor: Karen Osborn
Editor: Ted Blanco
Narrator: George Matsumoto
Motion graphics: Madeline Go
Production team: Heidi Cullen, Madeline Go, Larissa Lemon, Raúl Nava, Kyra Schlining, Nancy Jacobsen Stout, Susan von Thun
Music: Spectacular views (soft ambient deep piano) by Coastal Paul