1979] Haskins & Haskins — Rhytidoponera metallica 303 
#2 X #4 Test #1—Instant attack and seizure (A) 
Test #2—Open-mandibled encounters (B) 
#2 X #5 Test #1—Aggression; open-mandibled encounters (B) 
Test #2—Immediate aggression and attack (A) 
Summary 
Six tests among the Ashton populations were rated 3 each C and 
D. Two tests between Sutherland-location colonies were rated D 
and C. There was thus a notable degree of compatibility among 
colonies drawn from within both study areas, although within the 
Sutherland area collections were made over a fairly wide range 
(about 3 miles apart). 
In marked contrast, among 12 tests made between the Ashton and 
the Sutherland populations 5 were rated A, and 6 B. Incompatibility 
here was the general rule, varying only in the vigor of its expression. 
Tests within a single “colony”: 
As a final test of the adequacy of the method, tests were run on 
the same day between workers taken in the same collection. The 
results were: 
#1 X #1 Entire compatibility (D) 
#2 X #2 Entire compatibility (D) 
#3 X #3 Entire compatibility (D) 
#4 X #4 Entire compatibility (D) 
#5 X #5 Entire compatibility (D) 
It thus seemed clear (a) that the method itself was workable, and 
(b) that compatibility does diminish with distance, though “colo¬ 
nies” situated as much as three miles apart within the same study 
area (far beyond the likely bounds of daily worker encounters) can 
remain reasonably compatible, although at this distance there were 
often signs that workers were briefly “uncomfortable” in proximity, 
though they quickly adjusted. By contrast, members of widely 
separated populations (New South Wales and Queensland) uni¬ 
formly behaved in an antagonistic fashion. 
Is Compatibility a Conditioned or an Innate Perception and 
Reaction? 
This question was approached in two ways: 
(a) By introducing workers which had been eclosed from 
cocoons and had matured away from the parent “colony” (under 
