Steve Connor: If only we all had an extra couple of digits

Science Notebook: A kilogram, we now know, is the total amount of pasta you can eat in one go

The origin of units of measurement is said to be related to the dimensions and functions of the human body in some way or other. It makes the world more convenient for us, and literally gives it a human scale.

This is why we count to 10 and have a decimal system, for example. We have 10 fingers – well, eight fingers and two thumbs – and so a decimal system is a natural way of counting the world around us.

In fact, as any mathematician will tell you, a duodecimal system based on counting to 12 would be far more useful because we can divide 12 into equal parts so much more easily than 10. This is why the old British currency of pounds, shillings and pence was quite logical. If we had an extra couple of fingers then no doubt the decimal coinage system would never have gained a foothold.

The same is said to be true of other units of measurement that have a basis in the human body. A second in time is supposed to represent the interval between heart beats, the metre or yard the equivalent of a pace of two steps, and a foot represents, well, a foot. But what about a kilogram?

Professor George Efstathiou of Cambridge University offered a possible explanation last week at a presentation in London on the latest European Space Agency mission to study the cosmos. A kilogram is another unit of measurement chosen for our convenience, he suggested. "It's the total amount of pasta you can eat in one go," he said.

Campaign for caterpillars

The Met Office is predicting a hot, dry summer, which is a rare piece of good news in these plague-ridden times. It's also good news for our native butterflies, which have had to cope with two successive years of wet, cold washouts.

Our intrepid Environment Editor has highlighted the plight of our native butterfly species in his excellent coverage of the problem. The insects themselves are monuments of natural beauty and no civilised human being could argue with the need to protect these exquisite creatures.

As part of the campaign, I suggest that we should also see beauty in caterpillars – because it is almost certainly at this stage of their delicate lifecycles that they are at their most vulnerable. Yet so many people view caterpillars as ugly vermin. If only they could be made to realise that without them we wouldn't have the beauty of their adult forms.

Pity the ferret

Everyone's talking about pigs and birds in relation to influenza but no one seems to remember the poor old ferret. This vicious-but-cuddly darling of the northern working man's trouser leg also suffers from flu, just like humans. The trouble is, their symptoms are so similar to ours that they are used as laboratory models of the human disease.