The question is.........

[John Liddle]

...... how do the newly-hatched grubs know which direction to start munching in so as to fan out in a radial pattern where they don't cross each other?



Beetle tracks by John Liddle, on Flickr

[Trev B]

GPS John I have not got a clue, but like I’ve said many time, animals have got a lot more intelligence than we give them credit for.

[Skyelines]

Interesting question. For starters the grubs have only really got one direction to start munching and that is in the living phloem tissue that carries the nutrients around the tree. I would hypothesise that the munching of the grubs causes sound or vibrations that are sensed by the neighbouring grubs which they try to avoid. As the grubs get bigger the vibration/sound gets bigger so the grubs make extra efforts to avoid hence the fan shape develops.

[Farider]

No idea but it was certainly a good spot and a super pic!

Ian

[Daisy M]

Obviously Scottish, one lot taking the high road and the others taking the low.

[El Sid]

Interesting question. For starters the grubs have only really got one direction to start munching and that is in the living phloem tissue that carries the nutrients around the tree. I would hypothesise that the munching of the grubs causes sound or vibrations that are sensed by the neighbouring grubs which they try to avoid. As the grubs get bigger the vibration/sound gets bigger so the grubs make extra efforts to avoid hence the fan shape develops.

Sounds reasonable - might be some scent detection involved too.

Makes for a great shot however it happens...