The Red Notebook

I’ll have a starling shall be taught to speak
Nothing but ‘Mortimer,’ and give it him
To keep his anger still in motion.
     —Shakespeare, Henry IV, part 1

The other week, I came up with a frankly ridiculous hypothesis (I won’t dignify it with the description theory) about starlings [Sturnus vulgaris]. Ridiculous and fanciful though it undoubtedly is, I record it here, in the unlikely event that it turns out to be true, so that nobody else can take credit for thinking it up. It’s a priority issue:

A starling on my chimney pot

Starlings (or European starlings, to give them their international name, as we’re supposed to these days) are reasonably accomplished mimics. Not as accomplished, it must be said, as their close cousins the mynahs, but they have been known to imitate the sounds of other birds—and, indeed, man-made objects. As a child in the 70s, I well remember the local starlings’ occasionally imitating a neighbour’s Trimphone. In later years, as technology advanced, their descendants took to calling out like car alarms—a habit which seems to have died out as car alarms became more reliable, emitting false alarms much less frequently.

The collective noun for starlings is a murmuration. Indeed, when the birds congregate in the winter months and settle to roost, they do murmur incessantly to each other. But in amongst the murmurs, there are subdued snap, crackle and popping noises. The overall effect is uncannily like the noise made by Dr Frankenstein’s electrical apparatus just before he throws the master switch, or, less fancifully, a high-tension electrical transmission line.

Which is where my ridiculous hypothesis comes in. I am wondering whether the modern-day murmuration of starlings incorporates elements of electrical snap, crackle and pop, picked up by these semi-accomplished mimics as they gather for a murmur on electrical transmission lines.

No, I don’t think so either.

While clearing away yet more molehills from my front lawn the other day, I made an observation which is almost certainly pure coincidence, but which I record here for posterity, in case it turns out to be remarkably profound:

The holes in the middle of molehills almost invariably appear right underneath or immediately adjacent to dandelion plants. I wonder if moles deliberately choose to make their tunnel entrances next to dandelions. Perhaps dandelion roots are a good indication of where it is sensible/safe to surface.

That is all.

[T]he great tragedy of Science—the slaying of a beautiful hypothesis by an ugly fact…

Thomas Henry Huxley
Biogenesis and Abiogenesis (1870)

Back in 2002, I wrote an essay entitled (in tribute to Huxley) …So Let’s All Be Scientists! It was my contribution to Darwin Day Collection One: The Single Best Idea Ever [ISBN: 0972384405, Amazon.com], a collection of articles, reviews and cartoons in celebration of Darwin and science. In the essay, I observed:

…for all the thousands of slugs I have found, I have never come across a single snail in my garden. Why is that? Is it too cold (I live in the Pennines)? Do the slugs eat them […], or out-compete them? Am I just not looking hard enough? Or is there simply not enough calcium in the area to allow snails to make shells (possibly because the soil is too acidic)?

Well, it would appear that the not looking hard enough hypothesis had some merit. The other weekend, I was moving a rockery in my garden (don’t ask), when I came across this:

A very small snail!

OK, as snails go, it wasn’t exactly the biggest (or, indeed, the alivest), but a snail is a snail, and an ugly fact (no matter how small) is an ugly fact: my no snails in my garden hypothesis is well and truly falsified. So now I have had to modify it slightly:

There are no big snails in my garden.

Actually, I have been keeping an active look-out for snails ever since I wrote my essay, and I can confidently say that I believe my modified hypothesis is correct. Which is odd, because I have observed large snails a couple of hundred yards away from my garden, albeit at a significantly lower altitude (I live on a very steep hill).

But, despite this stark evidence to the contrary, I still like my acidic soil explanation for the (near) absence of snails in my garden. In fact, until last week, I was growing increasingly confident that it was the correct explanation, having first confirmed that the soil in my garden is indeed acidic, and having recently come across the following in the New Scientist subscribers’ archive:

Acid attack

Acid rain has progressively thinned the shells of eggs laid by British thrushes over the past 150 years, a new study suggests. Ornithologists fear that the trend could make thrush eggs less likely to hatch…

[Rhys Green of the Royal Society for the Protection of Birds] thinks that acid rain, caused by sulphur emissions from the burning of fossil fuels, is the most likely cause. This would reduce both the calcium content of leaf litter consumed by worms and the abundance of snails, which together make up a large part of the birds’ diets.

So maybe there is still enough calcium in my garden for some very small snails, but not enough for any snails bigger than a couple of millimetres across.

I will get to the bottom of this one! Eventually.

Postscript [18-Jun-2007]: Hypothesis well and truly falsified!