When pigeons feel heavier they are more confident

Pigeons and seagulls on the South Bank in London opposite Parliament

I’ve used the word “confident” in the title. I need to be a bit more precise in describing what happens to a pigeon’s mentality when you add weights to their legs. It sounds bizarre but this is what researchers did.

Pigeons and seagulls on the South Bank in London opposite Parliament. Photo: Negative Spaces on Pexel.

They wanted to test whether pigeons who were heavier than other pigeons became more confident and dominant and reached the top of the hierarchy where they could bully lighter pigeons who are the weaklings.

The interesting aspect of this research is that you can trick pigeon into believing that they are genuinely heavier and bigger by simply adding weight to them. It is an entirely artificial situation but immediately you add the weights the attitude and character of the pigeon concerned changes according to the research.

The researchers increased the weight of the birds by twelve percent which they decided was an amount which they would accept as occurring naturally. The neurological effect was instantaneous.

Dr Portugal, the lead scientist of the study at Royal Holloway University of London, said that he had noticed that the same birds were in charge and they were always beating up the others. It also became clear to him that they were the heavy ones. He felt sorry for the ones lower down the pecking order. He thought that if he could beef them up a little bit by making them heavier he may be able to improve their prospects in their challenges with the bully boys.

He said that as soon as he put the weights on the pigeons they had a little shuffle. He decided that that was an indication that they felt better immediately. He also decided that the pigeons with the added weight were no longer happy to take any rubbish from other pigeons. They would no longer tolerate it. So what is going on?

His assessment is that if a pigeon feels heavier the body tells a pigeon that they should be at the top of the hierarchal chain. Simply feeling bigger was enough to alter their mentality.

Carrying weights around was a slight handicap but the added self-belief was more important. He found that the top-ranked birds were “quite taken aback”. The hierarchies had been static for about three years. There was a sudden change and therefore an element of surprise.

The heavy boys at the top didn’t give in easily but the lightweights with the added weight kept coming back, persisted and eventually won. He found that the males who were at the bottom of the hierarchy grafting a meagre existence suddenly began to rule the roost.

Knowing this is important for further research because, for instance, when scientists are researching birds they sometimes need to add trackers to their bodies. This may alter their character and therefore the results.

When he removed the weights the old hierarchical order returned but he was glad that he had given the weaklings their moment of glory at the top. The research is published in Biology Letters, a Royal Society journal. Seventeen homing pigeons participated.

Comment: thinking about it, I’m not surprised. I think the same attitude can be found in humans. In humans size matters. Big people may feel more confident that they can dominate little people. There are other factors like intelligence but size is a factor. Of course you can’t trick a human into believing they are genuinely heavier by adding weight to them. But the same basic principles apply.