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Yes. I Googled "Ivan Chase" and found this page:

Here are three of his papers that are accessible there:

*1) VACANCY CHAINS  */Annu. Rev. Sociol. 1991. 17:133-54/

The concept of vacancy chains, originally developed in Harrison White's
pioneering analysis of organizational mobility processes, has been extended
to phenomena as diverse as national labor and housing markets, the
development of professions, gender and ethnic group discrimination in job
and housing markets, organizational demography, and the mobility of hermit
crabs to empty snail shells. In all populations in which they occur--whether
human or animal--vacancy chains appear to organize a variety of social
processes in nearly identical ways......

*2) Vacancy chains: a process of mobility to new
resources in humans and other animals
*Biology and social life, Biologie et vie sociale
Ivan D. Chase and Theodore H. De Witt

/*3) The vacancy chain process: a new mechanism of resource
distribution in animals with application to hermit crabs
*/Anim. Behav/., 1988, *36*, 1265-1274

*Abstract*. A number of resources important to humans such as jobs in
bureaucracies, houses and apartments are allocated through a mechanism
known as a vacancy chain. In a vacancy chain process an initial, vacant
resource unit entering a population of users is taken by a first
individual who leaves his/her previous resource unit behind, which is
taken by a second individual, and so on. In this process an initial
resource unit works both directly and indirectly to provide
opportunities for several individuals to gain new and better resources.
Vacancy chains are hypothesized to be important in resource distribution
for a variety of non-human animals, and it is documented, in particular,
that the hermit crab /Pagurus longicarpus /gets the gastropod shells in
which it lives through this mechanism. The direct and indirect effects
of vacancy chains on hermit crabs and the systematic ways in which
chains flow through groups of crabs and their resources are indicated.
In systems where they occur, it is further hypothesized that vacancy
chains have unique implications for the ecology of resource users.
several of these hypotheses are explored using the example of hermit crabs.

The vacancy chain process is a unique mechanism of resource allocation
that researchers have reported previously only in human populations.
Houses and apartments (e.g. Lansing et al. 1969; Sands & Bower 1976) and
jobs in bureaucracies (e.g. White 1970; Stewman 1975) are allocated
through this mechanism. Although researchers have not yet undertaken
formal studies, we pro- pose that major human consumer goods such as
automobiles (Smith 1941; White 1970), airplanes and boats also move
through vacancy chains. We demonstrate that vacancy chains also describe
the allocation of a vital resource in a non-human population, the
acquisition of gastropod shells by the hermit crab, /Pagurus
longicarpus/. We indicate how vacancy chains order the movement of
shells from one crab to another, and we explore the implications of this
type of resource allocation for the behaviour and fitness of crabs. (See
Chase & DeWitt 1988 for an initial report.)

He has links to related material. I found the one about "Giant Pacific
Octopus/ (octopus dofleini)/  to be especially interesting, perhaps
because this material, including the wonderful photographs, were done in
the waters around Vancouver, British Columbia. You can see how vacancy
chains work if you study them.



Don Steiny wrote:

>        Are any of Ivan Chase's papers on line?

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