An evolutionary perspective on laziness

The Science Lite team discover the ultimate excuse for laziness...

You’ll forgive the whiff of smugness this month from the Science lite desk. Above and beyond our regular vainglorious airs that is.

We have, after all, discovered the keystone to our existence. The very bedrock upon which, with out us knowing anything about it, our beings are built. We have, against all the odds, stumbled upon the scientific basis for our laziness.

Or rather, Professor Daniel Goldman has. The physicist and robotics expert at the Georgia Institute of Technology has spent a career mixing his many and varied academic skills trying to understand how organisms cope with locomotion on sand, mud and soil.

Not only that, his is not simply a rarefied academic pursuit. He is interested in nuts and bolts practicality. He reasons that understanding how creepy crawlies move and cooperate could have real-life consequences for robot design. And his lab is exquisitely built to this end with biomechanics experts, roboticists and rheologists rubbing shoulders to get to grips with creeping and crawling of all kinds.

On a go-slow Interesting… incredible even, but it all sounds very energy intensive doesn't it? Nothing much to do with laziness. Yet hidden in their latest paper is the Rosetta stone of laziness. Published in Science, the work set out to understand the group behaviour of fire ant colonies. They had noticed that when groups of interacting insects swarm toward a common goal they can form clusters that hinder the collective. So keen to carry out their tasks are the busy little tykes that they get themselves in a right old muddle. And its not just insects – any confined active systems, such as pedestrians or even traffic jams, can also exhibit this behaviour.

So, reasoned Professor Goldman, there must be evolved strategies to combat this. Evolution does so abhor inefficiency after all. And a mass of scrabbling insects causing a jam is nothing if not inefficient. So after setting around 30 or so ants in a habitat where they would excavate ­– having painted each one beforehand so they could monitor individual behaviour – they discovered something remarkable. It turns out a less busy approach in which some workers are purposely idle can avoid jams.

In a situation where physical constraints play a role – that is to say many ants in combination with small tunnels ­­– it really doesn’t pay to rush in.

“About 30% of the ants in a group did about 70% of the work. These six-legged swats were then hoisted out”

Not only that – those ants that are keen and do the most work get actively removed from the group! By monitoring which ants showed up in the tunnel, Goldman’s team found that in fact about 30% of the ants in a group did about 70% of the work. These six-legged swats were then hoisted out.

Robo-slob Now, team Goldman didn't stop there. They then built excavating robots which mimicked this behaviour and… well, perhaps it’s best to leave the final word to Dr Jeff Aguilar, who tracked and analysed the robots.

"The most interesting thing was this idea that if you are lazy then in certain cases, that is actually better. A ‘lazy’ strategy worked best in terms of energy consumed and rate of digging."

Oh evolution, you peculiar, beautiful thing. Do you know what you have done? You have emboldened us, that’s what. You have armed us for the next fraught editorial conversation in which we ordinarily flounder as we attempt to justify our painfully low word count each month. Thank you. The Editor doesn't stand a chance.