caa a22 4500 46578268X CHVBK 20180323111959.0 cr unu---uuuuu 170327e19901001xx s 000 0 eng 10.1007/BF00164894 doi (NATIONALLICENCE)springer-10.1007/BF00164894 Walter Arnold Max-Planck-Institut für Verhaltensphysiologie, Abteilung Wickler, D-8130, Seewiesen, Post Starnberg, Federal Republic of Germany aut The evolution of marmot sociality: I. Why disperse late? [Elektronische Daten] [Arnold Walter] Summary: Prolonged toleration of offspring in marmots was hypothesized to be (1) a means of preventing dispersal of undersized young (Barash 1974 a) or more generally (2) continued parental investment, increasing the probability of descendant survival and reproduction (Armitage 1981, 1987). These hypotheses are tested in this paper for one of the most social of marmot species, the alpine marmot. The animals studied lived in groups within territories defended by a dominant male and female, or as floaters lacking a well-defined home range. Offspring did not disperse before sexual maturity at age 2 (Fig. 1). Only territorial females bred, whereas territorial males were not able to monopolize reproduction likewise (Table 2). Dispersers had similar spring mass to nondispersers (Table 4). Hence, hypothesis 1 is not supported, at least not for adult-sized, > 2 years old animals. During their residency, 19% of subordinates obtained their natal territory or a neighboring one (Fig. 2). Long distance dispersal bore a high mortality risk. Thus, toleration of mature offspring could well represent parental investment. Other results, however, suggest additional influences on the timing of dispersal. (i) Males dispersed later than females (Fig. 3), possibly because of mate sharing by territorial males (see Emlen 1982). (ii) The higher mass loss of dispersers during the previous winter indicates that weak animals were forced to leave (Table 5) despite presumably lower chances of becoming territorial (Table 3). (iii) Subordinate animals which could not be the offspring of both territorials present were not more likely to disperse (Fig. 3). (iv) Lower dispersal rates when immatures lived in the group (Fig. 3) may indicate benefits from the subordinates' presence for rearing young. Springer-Verlag, 1990 Behavioral Ecology and Sociobiology Springer-Verlag 27/4(1990-10-01), 229-237 0340-5443 27:4<229 1990 27 265 https://doi.org/10.1007/BF00164894 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00164894 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Walter Arnold Max-Planck-Institut für Verhaltensphysiologie, Abteilung Wickler, D-8130, Seewiesen, Post Starnberg, Federal Republic of Germany aut NATIONALLICENCE 773 0- Behavioral Ecology and Sociobiology Springer-Verlag 27/4(1990-10-01), 229-237 0340-5443 27:4<229 1990 27 265 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer