Mollusk | Chapter 6 | Alone

The tropical coral reefs where many octopuses live are the metropolises of the underwater world: complicated cities of prey, predators, and lurid traffic. Yet the octopus is solitary. It races through the teeming underwater world a stranger, cleans its home alone, gives birth to children it will never see.

Being social has its perks and its perils. Families and communities share resources, protect each other, learn from each other, and make it easier to find a mate. But while humans cooperate, we also compete and spread diseases.

No matter the dangers involved in cooperation, social animals like us need our societies. We evolved to be raised by parents and to learn from those around us. A human alone is not as successful as a community of humans.

The octopus is our opposite: it lives fast and lonely. Every octopus is an orphan born into a mysterious world. They have to grow up fast, teaching themselves to hunt, feed and escape danger. They mature at a breakneck pace, increasing in body weight by as much as 5 percent per day.

Amphioctopus marginatus.  Christian Gloor

Amphioctopus marginatus. Christian Gloor

When a female octopus is mature and ready to mate, she finally abandons her solitary lifestyle for a brief encounter with a male. He doesn’t stick around after mating – he’ll die soon anyway.

She pours all of her energy not into raising children, but into creating them. Once she begins laying her eggs, she stops eating. She might not even sleep. She exhausts herself defending the pearly teardrops, wafting currents of oxygenated water over them until they hatch.

The first thing most baby octopuses see as they hatch from their eggs is their mother’s dead or dying body. The water around them is full of thousands of their siblings also struggling to emerge from their milky films, just a millimeter long.

Predators race overhead in great shadows, sucking down delicious strands of the hatchlings, but some octopuses make it through, drifting away from their siblings to begin their brief, lonely, technicolor bursts through life.


In 2012, biologists proved the existence of the first known social octopus. The Larger Pacific Striped octopus lives with its partner, and shares meals, and mates “beak to beak.” They hang out in groups of forty, but even the social octopus does not raise its children.
While most squid seem to lay their eggs on the seafloor and then leave the babies alone to hatch and develop, the deepwater Gonatus onyx squid broods her eggs. With hooks on her arms, she carries huge sacks of 3,000 eggs as she swims up to 7,000 feet below the ocean.
Off the rugged California coast, the deep-sea octopus Graneledone boreopacifica guards her fragile babies for an epic 53 months, longer than any other animal on earth.
Tiny, fragile baby octopus.  Matt Wilson/Jay Clark, NOAA NMFS AFSC

Tiny, fragile baby octopus. Matt Wilson/Jay Clark, NOAA NMFS AFSC