TYMPANIC TANTRUM

Bzzzzap

So I'm reading The Insects: An Outline of Entomology, and its authors (P.J. Gullan and P.S. Cranston) have introduced me to a brilliant little parasitoid of auditory interest.

Meet ormia ochracea, at left, a nocturnal fly who locates prospective hosts (male crickets and katydids), via sound, and then rather coyly uses them as larva hatcheries.

Interesting thing is, according to Penny G. and Peter C., the hearing mechanism in these flies is too small (1.5 mm) for them to determine sound direction via the traditional time-lag-between-ears method à la humans. Uniquely, they only have one auditory chamber containing two bulbae acusticae (basically one ear, two ear drums). These tympana are so close together that the timelag between sounds is only <1-2 microseconds.

To compensate, these flies boast a "cuticular structure" which functions as a sort of leaver between their "ears," magnifying the time and intensity differential between sounds by dampening the vibration from one tympanic membrane to another. So, they get two ears in one, and with hyper-accurate directional hearing. 

I thought this was awesome, and Google makes it look like a lot of other people do too (NPR apparently ran a piece on it in '99). Of course, Wikipedia mentions it, as well as £430,000 grant received by Uni. Strathclyde and MRC/CSO Institute for Hearing Research to develop a hearing aid based on it.

And here's the original (1994) article Penny'n'Pete refer to on the subject, if you happen to have an account at $pringerLink.

COLLECTING BUGS LIKE IT'S 1941

 A good friend of mine shared a little book from 1941 (first print 1936) endearingly entitled How to Know the Insects by Harry Edwin Jaques (who obligingly specifies the pronunciation of his name with a phonetic spelling on the title page: "Ja' - kwis").

In addition to providing a handy introduction to entomology, this miniature masterpiece features a homely guide to the manufacture and use of what Jaques calls "killing bottles." For those collectors who, Jaques says, "fear the deadliness of cyanide," there are other more benign options available: "killing agents such as chloroform, ether, gasoline, benzine, and carbon tetrachloride."

The book's 140-odd pages are fairly evenly divided between quaint 1930s wisdom on collecting/mounting techniques and information on the insects themselves (it's full subtitle is: An Illustrated Key to the More Common Families of Insects, With Suggestions for Collecting, Mounting and Studying Them). The whole is delightfully complemented with naturalistic line-drawings such as exhibit A at right: a hexagenia limbata, or giant mayfly.

 Actually, the book (which is available in full on the Internet Archive if anyone's interested) is worth taking a look at just for the drawings, which I can't find credited. But it takes a true prodigy to produce something of this unparalleled sublimity: