According to the results of Experiments 1 and 2, which of the following factors is (are) related to the dominance of one male grackle over other males?
I. Age
II. Body weight
III. Number of calls
A. I and II only
B. I and III only
C. II only
D. III only

Experiment 1
To determine what factors might affect aggressiveness, the biologists recorded the sequence in which the birds were placed in the cage, their weight, their ages, and the number of calls each grackle made during the experiment. In addition, the birds were ranked according to their aggressiveness toward each other, from most aggressive (1) to least aggressive (5). The results are shown in Table 1.

Experiment 2
The male grackles were placed back into the cage in the same sequence as in Experiment 1. The results of all aggressive encounters (number of calls) between pairs of birds were recorded. A bird was declared a “winner” if it forced the other bird, the “loser,” to flee from the encounter. Table 2 shows the results of the interactions between the birds. There were no draws (ties) observed.

Transcribed Image Text:

Grackle Sequence 1st 2nd 3rd ABCDE 4th 5th Table 1 Body weight (g) 200 325 300 340 350 Age in Number of Aggression months calls (rank) 6 18 12 24 30 17 34 29 12 24 4 1 2 5 3