Imagine you’re an octopus.
You can’t talk or even emit sound.
So what would you do to show you’re grateful?
Being an octopus, you’re all limbs — eight tentacles in all. Would you show your gratitude by getting near and use a tentacle to touch your benefactor?
That’s what a tiny octopus did.
A man named Pei Yan Heng found an octopus stranded in the sand of Cyrene Reef, Singapore. He saves the octopus’s life by scooping it into a cup, then releasing the little creature into the water. The octopus takes some time to recover, then swims over to the man (who is many, many times bigger), and gently places a tentacle on the man’s foot to show its gratitude.
Here’s Heng’s account of what happened:
Cyrene Reef 2013
Released a stranded octopus that got stuck on the sand when the tide went out in the shallow water. After recovering, the octopus moved towards my left booties and placed one of its tentacles on my booties for some time before moving off.
Note how the octopus changed color (got darker) when it was touching the man’s foot (1:28 mark), and that it rested its tentacle on the man’s foot for a full 23 seconds.
The video on YouTube elicited two comments about similar experiences:
Marc Johnson: “I know of another person who had the same experience. She worked at the Monterey Bay aquarium and was releasing an octopus in the bay that they had held captive for several years. As she released it, it came over to her and put one tentacle on her arm and looked straight at her for a long moment before swimming off.”
Terranaut157: “I witnessed identical behaviour in January this year (2018). A rescued, similar size octopus was put back into the water by hand. It swam off and then came back to embrace with one tentacle the hand that freed it – as if to say thanks – and then swam off again.”
Octopuses are highly intelligent creatures. From Wikipedia:
Octopuses are highly intelligent; the extent of their intelligence and learning capability are not well defined. Maze and problem-solving experiments have shown evidence of a memory system that can store both short- and long-term memory. It is not known precisely what contribution learning makes to adult octopus behaviour. Young octopuses learn nothing from their parents, as adults provide no parental care beyond tending to their eggs until the young octopuses hatch.:75
In laboratory experiments, octopuses can be readily trained to distinguish between different shapes and patterns. They have been reported to practise observational learning, although the validity of these findings is contested. Octopuses have also been observed in what has been described as play: repeatedly releasing bottles or toys into a circular current in their aquariums and then catching them. Octopuses often break out of their aquariums and sometimes into others in search of food. They have even boarded fishing boats and opened holds to eat crabs. The veined octopus collects discarded coconut shells, then uses them to build a shelter, an example of tool use.