Woodlice have personalities, say scientists

It may be small, grey and easy to ignore, but the humble woodlouse is big on personality, according to new research.

Dogs can be friendly or hostile, cats aloof or affectionate, and horses moody - but woodlice? They are individual characters too, scientists claim.

Tests on the way the creatures respond to being prodded, squeezed and dropped show that some are bold and others timid.

Even taking account of influences such as body size, they display behaviours that meet the definition of "personality", said the researchers.

The Czech team observed how the common rough woodlouse, Porcellio scaber, did what woodlice often do when threatened - feign death by curling up their armoured segmented bodies and tucking away legs and antennae.

Different individuals were more or less willing to adopt the "tonic immobility" (TI) strategy, some curling up for longer than others.

The way they differed was consistent across the range of tests, and when the experiment was repeated five times over a three week period.

Writing in the journal ZooKeys, the scientists led by Dr Ivan Hadrian Tuf, from Palacky University, Czech Republic, said: "There were some consistently more 'bold' woodlice (short TI) and some more 'shy' woodlice (long TI) ..

"Besides finding differences in endurance of TI between body size groups, we also identified personal behavioural patterns in all tested individuals, as well as variation within these body size groups."

They concluded: "Porcellio scaber is one of the first species of terrestrial isopods with documented personality traits."