Octopuses have alien brains and three hearts

These smarties have blue blood and brains that work totally unlike ours

By Smartasaurus· 1 min read Curious

Picture a creature gliding through the dark ocean, carrying three separate beating hearts

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The short version

These smarties have blue blood and brains that work totally unlike ours
The blood itself takes on a striking blue hue due to hemocyanin, a copper-based protein.
Octopus blood can lose 90% of its oxygen and still sustain the animal.

A single heartbeat pulses, strong and steady, through most of the animal kingdom. But beneath the ocean's sun-dappled surface, an octopus moves with three. Each beat propels a cerulean current, a visible divergence from the crimson flow of terrestrial life.

Two hearts, aptly named branchial hearts, dedicate their rhythm to driving blood through the octopus's gills, optimizing oxygen uptake from the water. A third, larger systemic heart, then circulates this richly oxygenated blood to the body's tissues. This triple-pump system becomes particularly crucial when the octopus swims, as its systemic heart must pause, leaving the body reliant on the branchial hearts alone for gill perfusion.

The blood itself takes on a striking blue hue due to hemocyanin, a copper-based protein. Unlike the iron in hemoglobin that binds oxygen in vertebrates, copper proves more efficient at low temperatures and reduced oxygen concentrations, conditions common in many marine environments.

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