There is a typically telling and intelligent Pixar moment in the film A Bug’s Life in which an already well-lubricated mosquito goes up to a bar and orders a ‘Bloody Mary, O Positive’. The barman plonks a droplet of blood down on the bar. The mosquito sinks his proboscis into it, sucks it down in one go and promptly falls over. The main point is that the mosquito doesn’t need a glass because that is for animals that have a problem with gravity. For insects the major force in their lives isn’t gravity at all, but surface tension.

The cleverness of the illustrators lies in them seeing this from the perspective of an insect when most of us ignore this kind of thing because our day to day lives are completely dominated by the invisible forces that define not only how we function but the form of our bodies and how we look and behave. Or, as the evolutionary biologist Stephen Jay Gould put it, “we are prisoners of the perceptions of our size”.

The link between form, scale and size is one that defines the natural world. The reason insects don’t grow as large as cows is because then they couldn’t be insects. They are constrained because they have evolved to meet the challenges of the world and the forces that act on them. Surface tension is as great a threat to insects as gravity is to larger animals such as humans because while a human covered in a film of water merely has to carry a pound of extra weight, a fly would have to carry many times its own weight. Conversely an insect falling from the top of a house won’t suffer at all while a person would have a big problem if gravity took hold of them.

The link between size and function

This fundamental law even applies to much bigger animals. For example, if the gazelle were to evolve into a much larger and heavier creature, its form would change dramatically. If it wanted to maintain its ability to move around quickly, it would need much thicker and shorter legs to support its increased weight. It would become something that looks more like a rhinoceros than a big gazelle. And that is precisely what happened when the common ancestors of gazelles and rhinos went their separate ways.

The culture and behaviour of large private sector organisations have more in common with large public sector organisations than those of small businesses

We can see similar issues arising when it comes to the functioning of businesses. This is perhaps most famously documented in the work of C Nothcote Parkinson, the creator of his eponymous law and also the author of a book which details how an organisation’s size affects its form and function.

This is clearly a problem for organisations themselves because it’s unlikely they can simply get bigger without evolving into a different beast. But it’s also a problem for legislators because they might assume that they are only dealing with large beasts who worry about gravity, when the legislation they introduce also affects those smaller organisations who are most concerned about surface tension. That is perhaps why the culture and behaviour of large private sector organisations have more in common with large public sector organisations than those of small businesses.

A book from the physicist Geoffrey West makes the complex relationship between scale and form evident. In Scale: The Universal Laws of Life and Death in Organisms, Cities and Companies, the author illustrates the point by describing how Godzilla simply couldn’t exist. A 350ft tall monster would simply collapse under its own weight, because an animal’s mass cubes with a doubling of its size. West makes the same point about cities which scale up in a super-linear way. When a city grows, its wealth, innovation and crime levels grow by a factor of 1.15 per head. West again summons terminology from nature to describe this compound growth, referring to it as ‘social metabolism’.