Thursday, 26 July 2012

Animal ecology and traps

A Whig history to justify my whacky interest

At the beginning was Charles Sutherland Elton, who established the Bureau of Animal Popultation and defined the field in 1927 with his classic book Animal Ecology. The picture below shows him in 1926 with a sack full of mouse traps setting off for Bagley Wood, the site of the first field study of voles and mice. Unfortunately, I do not know what type of traps he used. Anyone still alive to tell?
Charles Elton with a sack of mouse traps headed for a survey trip (I scanned this from Chitty 1996, p. xvi)

Dennis Chitty, who joined the Bureau of Animal Population later, and the Bureau's technician Denys A. Kempson designed ta small mammal trap (Chitty 1938). It has been produced by the Longworth Scientific Instrument Company Ltd of Abingdon, Oxfordshire. The trap is made of two parts, the larger back part can be provisioned with nesting material and food and taken off of the smaller trapping part in front. The popularity of this trap among researchers was a surprise and (Chitty 1996, p. 80) regretted not having patented it. The trap is still produced, but now has a small escape hole for shrews (voles and mice don't fit through and can't gnaw the chrome plated brass away either).
The Longworth small mammal trap.

During the second world war the researchers of the Bureau of Animal Population turned towards applied research with the aim of protecting the nation’s food supplies. The results of these applied studies were published in the three volumes of Control of Rats and Mice (Chitty 1954). After the war this applied approach was continued by the Rodent Research Department within the Infestation Control Laboratory of the UK’s Ministry of Agriculture located at Tolworth, Surrey. David Drummond joined the staff of this institute in 1953 and retired as chief scientific officer of the Ministry's Central Science Laboratories in 1988. Some time thereafter he began writing up what he had learned about rodent traps during his career and expanded this hobby. 

Eventually, I got interested in mouse traps because I simply did not believe that Michael Behe (1996) had checked the historical records properly, when claiming that mouse traps cannot have precursors functioning with one part less by virtue of being irreducibly complex. 
Behe's example of an irreducibly complex mouse trap consisting of 5 parts (fixtures not counted): spring, striker (hammer), catch-tradel-bait unit, holding bar, and platform (Behe 1996, p. 43), upon which he claimed that no such snap trap could possibly catch mice with only four parts.
It really only took a web search for the terms “animal trap” in a patents search engine and some patience to discover that the very patent (Hooker 1894) on which Behe’s mouse trap example hinged did have one part less, because spring and striker were formed of one wire. 
Drawing from Hooker's patent of 1894 showing clearly how spring (#4) and striker (#8) are made of one wire - two functions carried by one part.
Vintage specimen of the trap called Out O' Sight, produced by Hooker's Animal Trap Company according to his patent and showing the spring-striker unit.
But then I got involved with David Drummond's work, the surprising variety of mouse traps, and all that. 

So, hey, mouse traps have been among the first tools of your trade! It's up to you to reclaim an icon inanely seized upon by intelligent design poponents. 

  • Hooker WC (1894) Animal-Trap. US Patent 528671.
  • Elton CS (1927) Animal Ecology. Reprinted with new introductory material by MA Leibold and JT Wootton, Chicago Univ Press, 2001.
  • Chitty D, ed (1954) Control of Rats and Mice, vols 1-3. Claredon Press, Oxford. 
  • Behe M (1996) Darwin's Black Box. Free Press.
  • Chitty D (1996) Do Lemmings Commit Suicide? Beautiful Hypotheses and  Ugly Facts. Oxford Univ Press.
  • Mouse Trap Books by David Drummond.