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Mixed Diglossini, May 18, 1965, VI.  (49)

^[[185 186]] least ^[[double checkmarks]] 1CC ^[[3]]  with group. Following. Probably pair has been with group all the time. This is undoubtedly same group seen yesterday.  It seems to be very long untamed!  Now see that there is a single ^[[checkmark]] [[underlined]] cyanocephala [[/underlined]] with group. Also following.  All birds quiet. 2-4 ft up.

On way down hill, get another (very poor) view of same flock. Still includes Whitestarts and [[underlined]] cyanocephala [[/underlined]]. [[underlined]] Cyanocephala [[/underlined]] flies away. No one follows.

Leaving 10:20am

COMMENTS:
^[[Gen]] I. Although I did not see much fighting between Diglossini, and associates or competitors, in the area in which I worked today, this is not necessarily very significant.  As far as I know, the Diglossas and hummingbirds never fight with [[underlined]] Conirostrum [[/underlined]] species at higher altitudes in this region.  And, at least none of the species seen this morning associated with one another in an apparently non-hostile manner, as do (at least occasionally) some of the species at higher altitudes here.

^[[Gen]] II. The "general rules" controlling mutual Song inhibition might be summarized as follows. Any Diglossa species will tend to avoid overlapping the Songs of another species (of any group) when: (a) the Songs of the other species are very similar to its own Songs; (b) and/or the Songs of the other species are uttered very close by; (c) and/or the Songs of the other species are uttered very frequently (i.e. the Diglossa has become thoroughly familiar with them).

^[[Gen]] And all my observations tend to confirm the hypothesis that mutual inhibition of Song works but when species are [[underlined]] moderately [[/underlined]] motivated. At very high intensities, the species cannot "contain" themselves -