Sunday 16 September 2012

How is a Cricket Like a Rat?

The question posed is not intended to be a provoking thought experiment seeped in metaphor and it is not some lesser known Buddhist kōan. It is, in fact, a literal question to which a group of researchers recently attempted to answer.

How is a cricket like a rat? Insights from the application of cybernetics to evasive food protective behaviour (Heather C. Bell, Kevin A. Judge, Erik A. Johnson, William H. Cade, Sergio M):
ABSTRACT: Robbing and dodging is a well-documented food protective behaviour in rats. Recently, we demonstrated that a simple cybernetic rule, gaining and maintaining a preferred interanimal distance, can account for much of the variability in dodging by rats. In this paper, the field cricket, Teleogryllus oceanicus, was used to test whether or not the same or similar cybernetic rules are used by animals of different lineages and body plans. Pairs of female crickets were tested in a circular arena with a clear glass surface. A small food pellet was given to one of the crickets and the attempts to rob the food by the other were videotaped from beneath. The results show that, although crickets, unlike rats, use a variety of defensive strategies, all of the cases in which they use evasion to protect a portable food item conform to the same cybernetic rules used by rats.
There are essentially two interesting aspects to this article. The first, and the more complex of the two, is how the authors use an elaborate methodological design to test what variables were controlling the behavior of their crickets when stealing food. What the authors refer to as a 'cybernetic rule' is the idea that the "robber's" behavior is a result of a basic rule: maintain distance from other animals. The importance of this suggestion is that it proposes a rule that does not depend on an automatic stimulus-response algorithm, which would suggest that as a competing animal moves towards the "robber", there would be a fixed and constant reactive response from the "robber". The authors found this was not the case, and instead the crickets relied on the same rule that had previously been observed in rats, where their behavior was constantly modified through experience and a changing environment - the cybernetic rule. The authors summarise their results as such:
CONCLUSION: Like rats, crickets are able to protect food from being stolen by other crickets by using evasive strategies. The two types of evasion used by crickets (running and dodging) both adhere to the cybernetic ‘gain and maintain the preferred interanimal distance’ rule that is used by rats, despite the large differences in their body morphology and their mechanics of locomotion. Not only does this show that cybernetic rules can be applied to two different organisms, but also to organisms from vastly different evolutionary lineages, supporting the idea that cybernetic rules may be widely, if not universally applicable (Powers 1973). This possibility has wideranging implications, both for understanding the behaviour of organisms and for the development of artificial systems (e.g. robotics).
The second interesting component of this article is how sometimes it is possible to judge a book by its cover; or, in this case, a scientific article by its title.

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