So, Tube mice. A topic I’ve been meaning to write about for ages, and after hours of exhausting(!) research, I still have more questions than answers.

Those of you unfamiliar with the London Underground system may not be aware of the variety of fauna that lives in the tunnels – for example, a whole new type of mosquito was discovered not long ago, as reported on BBC news having first gone down in the system when the tunnels were dug in Victorian times, and then breeding in isolation and producing genetically different strains not only different to the ones on the surface, but also between tube lines that never cross.

There appears to be less research done on the mice, however. What I want to know is, why do they only come out at night? No, it can’t be because everything is quieter – they emerge when there is still another 4 or 5 hours of train activity left, and when stations are as busy as they are in the rush hour. Is it because evening people tend to drop more food in the form of kebabs, chips etc than their daytime counterparts? Or is it because tube mice, like any other mice, prefer to come out at night and know it’s night time even though they are in a tunnel deep below the surface of the earth and have never seen natural light in their entire lives?

Similar to the mosquito thing – and this one is somewhat subjective, but I’m pretty certain mice on the Piccadilly Line have longer tails than those on the Northern Line. It’s possible, after all, with tube lines running at different depths, it’s likely that mice as well as mosquitos have thousands of generations between them.

And another strange thing – why are they the exact same colour as the track floors? The photos here are a bit misleading since the floor has come out pale grey and the mouse a deep brown, it must be due to the effects of the flash - but when you look at them in real life they are the exact same very dark, grimy brown. I’ve had pet mice before, brown ones, and they don’t naturally come in that colour. Now the easy answer is that they’re dirty, but I don’t go with that. Mice wash – a lot. I haven’t caught one yet, but I’m pretty much convinced that that is the colour of their fur. But why do they need to camouflage themselves so effectively against the background? Do they have any natural predators round there? Are there as yet undiscovered tube cats on the prowl?

If anyone has any answers, please drop us a line and we’ll put it in Part 2.