||Patrol/Marking Motivational System and Its Unity||Page 22|
Territoriality, which is an important aspect of agonistic behavior, depends upon a set of behaviors that have been called "patrol," and which include the locomotor activity of dominant males who periodically and systematically make the rounds of their territories. Since the term was initially used to describe this behavior in M musculus by Crowcroft , it has been applied to comparable behavior of dominant males of D groenlandicus [Brooks and Banks, 1973], A sylvaticus and C glareolus [Brown, 1966], Aethomys chrysophilus [Choate, 1972], Ne florid ana [Kinsey, 1976], and Ps obesus [Daly and Daly, 1975]. Patrol behavior is accompanied by scent-marking, although this is not always noted by observers. It has been documented, however, in Mer unguiculatus [Roper and Polioudakis, 1977], C glareolus [Mironov, 1976], Cr gambianus [Ewer, 1967], and N alexis [Stanley, 1971].
Not only dominant males, but also estrous females engage in behaviors corresponding to patrol and marking. In the rat, this has been observed in field settings [Calhoun, 1962, p 153], and documented in laboratory studies on estrous increases in locomotor activity [Wang, 1923] and scent-marking [Birke, 1978]. In a previous publication [Lehman and Adams, 1977] we referred to these behaviors as "exploration/marking," but in view of the fact that exploration may also be a behavior activated by hunger and other motivational systems, it is more accurate to restrict the term to "patrol/marking" instead.
Unity of Patrol/Marking Motivational System
The initial hypothesis that there is a single motivational system of patrol/marking stems from the behavioral sequence analysis of isolation-induced fighting in rats, in which the motor patterns of approach locomotion, urine-marking, and sniffing of objects and the intruder were found to be temporally related. Therefore, it was hypothesized that all of these motor patterns were activated by a single homogeneous set of neurons which could be called a motivational mechanism [Lehman and Adams, 1977] .
Three types of supporting evidence may be added to the initial temporal-sequencing data: 1) The fact, to be documented below, that all of the various motor patterns of patrol/marking depend upon the same motivating stimuli; 2) the simple and consistent action of the gonadal hormones, androgens, and estrogens (which facilitate the entire motivational system of patrol/marking) suggesting that they may act upon a single set of neurons which integrate the system; and 3) suggestive evidence for the location of a motivational mechanism of patrol/marking in the preoptic hypothalamus. The hormonal and neural data are obviously critical to the ultimate resolution of the question, but cannot be reviewed here and will be considered elsewhere.