RICHARD WILLIAMSON: ‘Undertakers’ of insect world worth a look

The sexton beetle
The sexton beetle

A READER sent me a beetle in a box. And here is the beastie, casting its enormous shadow in the photograph I took of it on the kitchen table.

‘What is it?’ asked the reader, who lives in Chichester. She had already asked friends and neighbours. They had never seen anything like it either. Unfortunately the beetle was dead, she said, drowned in a bowl of water used for indoor plants. She could find no picture in any book.

Well, these are the creatures of the underworld, those places we hardly want to know about, the dark caverns best left to these specialists. They belong to what entomologists call a superfamily, in this case the Silphidae: in a word, sextons. Undertakers if you like.

They fly for miles looking for trade. Sometimes they get thirsty on their travels and stop for a drink, which is how this one died accidentally. Where was it going? Somewhere within a mile was a body, waiting to be buried, placed properly underground where it was of no nuisance to society. Maybe the remains of a dead pigeon half-eaten by the peregrines, or a mouse in a meadow which died of old age, or even kitchen waste on a compost heap on someone’s allotment.

Necrophorous vespilloides

was answering the call of nature for which it was designed. Without it and all the other 60 species of burying beetles, we would be plagued with filth which rats and red kites would never be able to deal with.

These gravediggers fight for the job. If a female beetle arrives, she will allow a male to help her, and vice versa. Together, the pair will fight off rivals. They will dig a deep pit under the corpse, tearing away roots with their teeth. Sometimes they will amputate limbs from the body to allow it to sink slowly downwards.

They may even drag it to ground which is easier to dig. I have watched them doing this removal job by turning over on to their backs underneath the load and pushing with their legs.

At last it has disappeared. Now they get to work to raise a family. Or at least she does. He might disappear from the domestic and be off on his travels. On the other hand, he might just dig himself a little burrow in the cemetery as he wonders what to do with himself.

Just resting is quite a favourite occupation for the males. She, however, is busy making food parcels for her babies. They are fat white maggots who wait for mother to give them food in the crèches she has provided underground.

Eventually the family grows up and the youngsters turn into beautiful black and orange adults. Now comes the weird bit in this wonderful story of necrophiles. For some inexplicable reason to us, the parents fight and kill each other off. Since they are surplus to requirements this is just another example of nature tidying up the environment I suppose. We call it recycling.