The fungus capable of mind-control ๐Ÿ„

In June I was down on the Sussex coast at the mouth of the river Cuckmere. During a bioblitz event I was supporting I discovered something I never expected to see. At the foot of either the first or seventh of the Seven Sisters cliffs, the fenceline and surrounding grasslands were alive with invertebrates. One large thistle plant was covered in all kinds of insects. I felt especially drawn to a beautiful orange and black ichneumon wasp clambering over the spiny leaves. But there was something else that caught my eye.

The fly as found

I noticed a dead fly in a quite unnatural position, a bit like an upside down koala. It was clamped onto one of the spines in a way that reminded me of the famous victims of the parasitic ‘zombie fungus’ cordyceps. Luckily I had my macro lens with me and could get a close-up of the fly.

The fly after I had bent the spine tip of the plant over

The body looked an unusual shade for this species and, looking closer, you could see it was kind of mouldy. I showed everyone I could, taking away the images and several questions I needed to answer for myself!

That afternoon I put the photos on Twitter and had a quick reply from Lukas Large, a known fungi expert in the UK. He said it was a species of entomophthora, a group of fungi that kill flies, just as this one had done. It does much more than that beforehand, however.

Somehow, the fungus enters a final stage of mummification where it ‘gains control’ of the fly’s brain and therefore control over its functions. The fungus is then able to make the fly move to a high position in order to disperse its spores from the dead fly. That is mind blowing in more ways than one.

Thanks for reading.

Latest from the Blog

The Sussex Weald: Autumn sunset at Cowdray Park

A new blog post series of single images, maybe, to counteract the decline of Twitter and the TikTok-isation of Instagram? This image was taken at Cowdray Park near Midhurst on Monday 14th November. It was a stunning autumn evening, with trees in shades of gold, yellow and orange all the way to the sumptuous Downs.

The lackey in the Cuckmere valley ๐Ÿ›

I was out and about in the Cuckmere Valley in May and had the chance to learn a little bit about some of the species found there. Here’s a small selection of images, a blend of phone pics and some from my camera.

Once again I was treated to the sight of early spider orchids, a plant I blogged about only recently. This was a big surprise, having spent a lot of time looking for them elsewhere. This is a nationally rare plant and I won’t be giving away its location. I did get the chance to learn that the flower mimics the scent of the buffish mining bee. The male bee is lured in and attempts to mate with the flower, thereby pollinating it. In the photo above you can see the pollen grains that have been helpfully, accidentally, applied by the visiting bee.

The mining bees live in the nearest exposed areas of chalk where they drill their burrows. It’s a short commute to their deceptive orchid neighbours.

The blackthorn hedges were holding populations of moth caterpillars that cover the branches in webs of silk. This is the kind of thing that pops up in local newspapers as some kind of wild clickbait. The moth is known as the lackey in English. What the significance of that name (or any of the number of weird moth names) is unclear to me.

We found this proto-Mesolithic (Stone Age) scene, with a discarded King Alfred’s cakes fungus. The fungus had probably been used to maintain the fire of one or more disposable barbecues. The stones were littered across the scorched earth like the throwaways of some prehistoric stone mason.

On the banks of the Cuckmere’s static meanders are ranks of hoary cress. At first I thought they looked like a type of sedum but in fact they’re in the cabbage family. This is an introduced species.

A view back up the Cuckmere meanders, at very low levels for the time of year. Two little egrets can be seen here.

Thanks for reading.

More macro (my tags/categories seem to be broken at the moment – will try and fix them!)

The South Downs