Ants Can Expect the Time of an Event on Basis of Previous Experiences

Table 1

Number of ants of four colonies of Myrmica ruginodis counted on the food site at five successive times during five consecutive days, the food being delivered during 15 min at a given time “” which was delayed for 20 min each day.

Days, food delivery times, and counting times ()	Colonies				Mean
	A	B	C	D
Control 1, no food
	0	15	5	5	6.3
= + 20′	1	0	10	6	4.3
= + 40′	3	2	7	5	4.3
= + 60′	8	2	3	10	5.8
= + 80′	4	4	4	7	4.8
Control 2, food present
	10	0	5	10	6.3
= + 20′	10	0	5	3	4.5
= + 40′	5	0	5	5	3.8
= + 60′	5	4	5	3	4.3
= + 80′	10	0	5	5	5.0
Day 1, food given at and retrieved at the end of
	10	7	6	0	5.8
= + 20′	2	4	22	5	8.3
= + 40′	0	2	3	7	3.0
= + 60′	2	7	5	0	3.5
= + 80′	1	4	7	1	3.3
Day 2, food given at and retrieved at the end of
	5	0	4	2	2.8
= + 20′	11	13	26	6	14.0
= + 40′	5	9	8	8	7.5
= + 60′	0	13	10	0	5.8
= + 80′	0	2	11	5	4.5
Day 3, food given at and retrieved at the end of
	0	9	3	8	5.0
= + 20′	3	4	2	5	3.5
= + 40′	15	11	31	13	17.5
= + 60′	10	7	9	8	8.5
= + 80′	2	7	10	4	5.8
Day 4, food given at and retrieved at the end of
	1	7	7	5	5.0
= + 20′	6	4	5	2	4.5
= + 40′	1	9	11	6	6.8
= + 60′	18	14	18	27	19.3
= + 80′	1	10	4	18	8.3
Day 5, food given at and retrieved at the end of
	7	0	8	3	4.5
= + 20′	5	2	6	6	4.8
= + 40′	1	7	9	2	4.8
= + 60′	6	3	7	12	7.0
= + 80′	15	18	27	27	21.8