Erinjery Joseph J, Kavana Theethira S, Singh Mewa
Biopsychology Laboratory and Institute of Excellence, University of Mysore, Mysore, India.
Folia Primatol (Basel). 2017;88(3):293-306. doi: 10.1159/000480010. Epub 2017 Sep 22.
Studies that compare differences in the behavioural variability across species and genera are rare among south Asian primates. Such studies are important for understanding within-group feeding competition in primates as interindividual difference in frequency of behaviour is a good indicator of feeding competition. We compared the variability in individual activities of lion-tailed macaques, bonnet macaques, Nilgiri langurs, and black-footed grey langurs. Both macaque species showed variability in their activities, with bonnet macaques showing higher variability than lion-tailed macaques. This indicated higher within-group competition in bonnet macaques than in lion-tailed macaques. Folivorous Nilgiri langurs and black-footed grey langurs did not show variability in any behaviour, indicating weak or negligible within-group competition. Except in the bonnet macaque, the interindividual differences in activities in the other species were potentially due to the differences between lactating and non-lactating females. We observed that langurs were less variable than macaques, indicating higher within-group competition in macaques than in langurs. We also observed a higher frequency of aggressive interactions during feeding among macaques than langurs, substantiating higher within-group competition in macaques than in langurs. We further discuss the different possibilities of within-group contest and scramble competition in these species.
在南亚灵长类动物中，比较不同物种和属之间行为变异性差异的研究很少。这类研究对于理解灵长类动物群体内的觅食竞争很重要，因为行为频率的个体差异是觅食竞争的一个良好指标。我们比较了狮尾猕猴、冠毛猕猴、尼尔吉里叶猴和黑足灰叶猴个体活动的变异性。两种猕猴在活动中都表现出变异性，冠毛猕猴的变异性高于狮尾猕猴。这表明冠毛猕猴群体内的竞争比狮尾猕猴更强。食叶的尼尔吉里叶猴和黑足灰叶猴在任何行为中都没有表现出变异性，表明群体内竞争较弱或可忽略不计。除了冠毛猕猴外，其他物种活动的个体差异可能是由于哺乳期和非哺乳期雌性之间的差异。我们观察到叶猴的变异性比猕猴小，这表明猕猴群体内的竞争比叶猴更强。我们还观察到猕猴在进食期间的攻击性互动频率高于叶猴，这证实了猕猴群体内的竞争比叶猴更强。我们进一步讨论了这些物种群体内争斗和争夺竞争的不同可能性。
