15 December 2009

Man takes another step down from the pinnacle of creation

Man is a tool-using animal.
Thomas Carlyle (1795-1881)
Humans have long ago relinquished their claim to be the only tool-using animals. But now that the octopus, only a lowly mollusk for crying out loud, has been shown to use tools*, we should eat the humble coconut pie and settle down in our spot among our evolutionary relatives.

The octopus Amphioctopus
in its shelter of coconut shells. From Figure 1 in Finn et al.

*Julian K. Finn, Tom Tregenza, Mark D. Norman. Defensive tool use in a coconut-carrying octopus. Current Biology - 15 December 2009 (Vol. 19, Issue 23, pp. R1069-R1070). Abstract & open access pdf. Don't forget to watch the movie!


Anonymous said...

Ah, terrific! They are so very smart! I kept a very small Octopus bimaculatus in a tank in my home for a couple of months, years ago when I lived in Southern California. It was a fascinating animal.

Susan J. Hewitt

Psi Wavefunction said...

Hmmmm...does building a test out of grains of sand qualify as tool use?

In which case caddisfly larvae have already been at it. As have a lot of other things, like some ciliates, various testate amoebae like Difflugia, some forams, etc. Also, if I recall, different species/genera of Difflugia use different materials for their test -- I wonder if anyone checked how context specific it is, or whether they actually pick the material. Would be really interesting if they have ways of sorting what they want their shell to be made of!

After all, instinct and behaviour are, fundamentally, molecular/biochemical, so I'm not too shocked by the idea of single cells having behaviour just like the rest of us!

I need to get back to cramming for biochem... I can feel my life drain out as I look at the course notes again... zzzzZZZ (how one can make a class about HOW LIFE WORKS so painfully boring is beyond me...)


I don't think building a nest or a shell or a case qualifies as a tool use. Read the paper for the authors' arguments along those lines: "A tool provides no benefit until it is used..."

Therefore, following their definition, if a hermit crab carried in its claws a shell bigger than the one it was wearing with the demonstrable intention of moving into it in the future after it had outgrown the present one, it would be using a tool.

Frank Anderson said...

We haven't stepped down -- octopuses have just stepped up! And they've probably been doing this for a very long time, but we only just found out about it. But I love the continued shredding of the supposed chasm between us and the other animals.

Joel VanDerMeulen said...

How very coincidental.

I was just watching Daily Plaent where they showed the footage, and I was going to post about it.

BUT! It seems you've beat me to the punch :P. It's only natural though I suppose.

On the topic though, very cool! One of the scientists that witnessed the event was saying how "It was one of those moments where you spill your tea on your lap", and that the actual divers were laughing so hard they almost blew their respirators out.

Kevin Zelnio said...

I disagree about hermit crabs. They are clever enough to notice the plethora of shells. Being the ultimate minimalists they are, they choose to switch shells when they can. It is still use because they can exist without a shell. In fact, they must exist without a shell until they are big and strong enough to carry one around.

Once again, arthropods FTW.