An inordinate fondness for beetles

Ground beetles, in the garden pitfall trap during a seven day period (nb these are not to scale). There were other kinds of beetles in the trap - several species of Rove beetles for example these are just the Carabidae - Ground Beetles

The biologist J.B.S. Haldane is reputed to have been asked what could be concluded about the nature of god from a study of his creation -  his reply was that he has -  "An inordinate fondness for beetles."

Yes there are a lot of beetle species - nature has got beetles coming out of its ears. I had my own taste of this during my week long 'beetle drive' (fans of pointless stuff your parents used to do should check out the beetle drive). I put a pitfall trap in the garden - this being a glass jar placed into a hole in the ground. Beetles stumble into the trap and can't get out - simple, yet...erm...simple.

Almost every time I inspected the trap - I would see one or two ground beetles scurrying around and bumping into each other like tiny dogem cars. Black and shiny and all the same - until closer inspection revealed them to be mostly different species  - an inordinate fondness indeed.

There are are around 400,000 described species of beetles (and probably over a million in total), compared to 5,487 species of mammal, for example.

Why are there so many species?

A number of suggestions have been put forward:
  • Many beetles are plant feeders and plants provide a large number of ecological niches.
  • As they go through metamorphosis the different stages are able to exploit a range of habitats.
  • As they have a hard exoskeleton they are able to withstand extreme conditions. 
  • Some groups are innately good at speciation.
It has also been suggested that, as beetles are a relatively old group they have had longer to diversify than newer groups such as mammals. There are, however, other orders of a similar vintage which are nowhere near as diverse as beetles.

Recent studies of the fossil record indicate that the key factor is that beetles tend to be extinction proof.  So while they're good at producing new species they're even better at not going extinct - and clearly didn't pass on any tips to the dinosaurs.

Very few beetle families have ever gone extinct through their evolutionary history.

This begs further questions however - why are beetles resistant to extinction? Why are there so many insects per se, and indeed why are there so many species of anything?

In common with the reggae song by Johnny Nash this blog has 'more questions than answers'.
Ruptela maculata
Phyllobius glaucus
Athous haemorrhoidalis
Gastrophysa viridula

Black Sexton Beetle (Nicrophorus humator)

I quite often catch beetles in the moth trap and particularly the carrion eating sexton beetles - these have a fascinating mutual relationship with mites.

Mites of the genus Poecilochirus produce nymphs that crawl on the beetles and are transported to carrion. Once they arrive at the carrion the mites leave the beetle and proceed to feed on nearby fly eggs and immature larvae.

Mites help sexton beetles reduce the amount of competitors on carrion. With less competition the beetles' larvae have a better chance of maturing to adults."

It's win-win - the mites get free transport to sources of carrion - the beetle larvae get more food - hoorah!

Rosemary beetle (Chrysolina americana)

This beetle originates from southern Europe and has been found in Britain since the mid-1990s. It feeds on Rosemary and Lavenda and is now considered a pest

It's a bit of a beauty though!

Scarlet lily beetle (Lilioceris lilii)

Sometimes wildlife should come with a Parental Guidance warning!

Carabus nitens

My blog rule is that I only include wildlife from the patch - I've made an exception for this jewel of a beetle however found in the Bowland Area

Get this


  1. I do like that "an inordinate fondness for beetles" quote. Lots of beautiful examples in your post - we've had a few of the lily beetles here - not that we have lilies - but they like snake's head fritillaries too (I relocated the beetles). The rosemary and 'carabus nitens' are particularly pretty! :)
    Hope you've had a great time away. :)

    1. Yikes that was full of typos should have read through it again.

      Hols great thanks, Nightjars and Chinese water deer from the tent, Dartford warbler as well, saw lots of prehistoric sites as well - Avebury, silbury, Badbury rings etc, also Brownsea Island, New Forest, Jurassic coast


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