Goncharov Denis, Policht Richard, Hambálková Lucie, Salovarov Viktor, Hart Vlastimil
Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences Prague, Kamýcká 129, 165 00 Praha 6, Czech Republic.
Irkutsk State Agrarian University, 59 Timiryazev St, Irkutsk 664038, Russia.
R Soc Open Sci. 2021 Feb 24;8(2):200147. doi: 10.1098/rsos.200147.
Based on their phylogenetic position, Nearctic ground squirrels are closest relatives to the long-tailed ground squirrel even though it has Palaearctic distribution. We aimed to investigate the variability of alarm calls of the long-tailed ground squirrel to test the individual variation in alarm calls. This species is known to produce two types of alarm calls: whistle alarms and wideband calls. Although ground squirrels are a model group for the study of vocal individuality, this phenomenon has not yet been studied in a species producing two such completely different types of alarms. Most of ground squirrel species produce either whistle or wideband alarms and this species represents a unique model for testing the degree of individual variability depending on completely different acoustic structures. We analysed 269 whistle alarms produced by 13 individuals and 591 wideband alarms from 25 individuals at the western part of Lake Baikal. A discriminant function analysis (DFA) assigned 93.5% (88.9%, cross-validated result) of whistle alarms to the correct individual and 91.4% (84%) of wideband alarms. This is the first evidence of individual variation in wideband alarms compared with whistle alarms and occurrence of vocal individuality in two warning signals of a completely different acoustic structure produced by a ground squirrel.
基于它们的系统发育位置，近北极地松鼠是长尾地松鼠的近亲，尽管长尾地松鼠分布于古北区。我们旨在研究长尾地松鼠警报叫声的变异性，以测试警报叫声中的个体差异。已知该物种会发出两种警报叫声：哨声警报和宽带叫声。尽管地松鼠是研究声音个体性的典型群体，但在一个能发出两种如此截然不同警报类型的物种中，这一现象尚未得到研究。大多数地松鼠物种要么发出哨声警报，要么发出宽带警报，而该物种代表了一个独特的模型，用于测试取决于完全不同声学结构的个体变异程度。我们分析了贝加尔湖西部13只个体发出的269次哨声警报和25只个体发出的591次宽带警报。判别函数分析（DFA）将93.5%（交叉验证结果为88.9%）的哨声警报归为正确的个体，将91.4%（84%）的宽带警报归为正确个体。这是与哨声警报相比宽带警报中存在个体变异的首个证据，也是地松鼠发出的两种声学结构完全不同的警报信号中存在声音个体性的首个证据。
