Abstract
Young Formica rufa L. workers of the same age were kept in complete absence of cocoons during their first 23 days after hatching. Given subsequently a choice between homo- and heterospecific (Formica lugubris Zett.) cocoons, these workers showed no recognition nor nursing behaviour for any cocoon-type. It has however been possible to evoke an indiscriminate cocoon-nursing behaviour in F. rufa workers raised, during their whole sensitive period, in complete absence of cocoons which nevertheless, just prior to the choice-test, had been allowed to observe the nursing procedures performed by adult workers (of the same colony) with “normal” adoption behaviour towards homo-specific cocoons. The results are tentatively interpreted and the possible role of social transmission in the nursing behaviour of cocoons in F. rufa is stressed.