2 april 2010

Here's that famous passage from Darwin's last and best-selling book,

Worms do not possess any sense of hearing. They took not the least notice of the shrill notes from a metal whistle, which was repeatedly sounded near them; nor did they of the deepest and loudest tones of a bassoon. They were indifferent to shouts, if care was taken that the breath did not strike them. When placed on a table close to the keys of a piano, which was played as loudly as possible, they remained perfectly quiet.

- Darwin, The Formation of Vegetable Mould through the Action of Worms, with Observation on their Habits, 1881

and now the southern charm and whimsy of Fabre:

Of my experiments in this matter, I will mention only one, the most memorable.

I borrow the municipal artillery, that is to say the mortars which are made to thunder forth on local feast days. The gunner is delighted to load them for the benefit of the Cicadae and to come and fire them off at my place. There are two of them, crammed as though for the most solemn of rejoicings. No politician making the circuit of his constituency in search of re-election was ever honoured with so much powder. We are careful to leave the windows open, to save the panes from breaking. The two thundering engines are set at the foot of the plane-trees in front of my door. No precautions are taken to hide them: the Cicadas singing in the branches overhead cannot see what is happening below.

We are an audience of six. We wait for a moment of comparative quiet. The number of singers is assessed by each of us, as are the strength and rhythm of the song. We are now ready, with ears pricked up to hear what will happen in the aerial orchestra. The mortar is let off, with a noise like a genuine thunder-clap . . .

No consternation whatever up above. The number of performers is the same, the rhythm is the same, the volume of sound the same. The six witnesses are unanimous: the mighty explosion has in no way affected the song of the Cicadae. And the second mortar gives an exactly similar result.

What conclusion are we to draw from this persistence of the orchestra, which is not at all surprised or put out by the firing of a gun? Am I to infer from it that the Cicada is deaf? I will certainly not venture so far as that; but, if any one else more daring than I were to make the assertion, I really should not know what arguments to employ in contradicting him. I should be obliged at least to concede that the Cicada is extremely hard of hearing and that we may apply to him the familiar saying: to bawl like a deaf man.

- Fabre, Souvenirs Entomologiques, 1897

Two great scientist naturalists, working at the top of their game, and yet we now find it so easy to draw conclusions and make connections that they were sometimes unable to accomplish. To be fair on Darwin, he soon found that worms were sensitive to vibrations through their flowerpot containers when placed on the top of the piano, but Fabre never figured out that the auditory range of cicadas might not include the frequencies generated by cannon fire.

Postscript: White was at it too:

When we call loudly thro' the speaking trumpet to Timothy [White's Aunt's tortoise], he does not seem to regard the noise.

- Gilbert White, Journals, September 17th 1780

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4 april 2010

Now obsessing about cicadas. Wondering whether cicada is superceding worm as the year's totem animal. Reading J.G.Myer's book Insect Singers on the subject:

The adults are devoted wholly to Apollo and Eros . . .

How like my own household this seems!
Various experiments and methods of attracting cicadas using sound are described, including an investigation whereby Lataste (apparently le Roi du Crazy as far as these things go, working in Chile in the 1890s)

. . . made a machine, which, with the aid of a watch movement, produced at will either sounds, more or less like those of the cicada, or silent but visible vibrations. This was designed to ascertain whether the insects were drawn to the sound or to the movement; but unfortunately they remained entirely insensible to this instrument.

Undeterred by this setback, Lataste then tried (with some success) a different approach:

He then had an assistant clad in obscure vestments hide under the bushes and clap his hands, while the author, dressed in white, stood in the open and made the same motions silently. A cicada flew at once to the aide and perched on the bush which hid him. But on the aide ceasing to clap, and Lataste clapping himself, the cicada flew at once to the latter.

Sometimes these things appear to be a matter of tradition:

Annandale (1900) and Skeat (1900) describe a regular practice among the natives of the northern portion of the Malay Peninsula. For half an hour after sunset several men gather round a brightly burning wood fire, one of them holding a lighted torch. The others clap their hands at regular intervals, and the cicadas, Pomponia intemerata (Walk.), apparently attracted by the noise and guided by the light, fly down and settle upon the people as they stand by the fire.

This of course in the days before television. Finally one more extract which makes tears of nostalgia spring to the eyes:

Gadd . . . quotes an oral communication from the well-known Russian Hemipterist, Oshanin, that in Turkestan cicadas are attracted to the post-wagons by the noise of the bells on the horses' harness.

Makes one want to spend the summer reading Pushkin.

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