Variation of in-air female Weddell seal contact calls

From the abstract of the attached paper:Vocal recognition may function as a critical factor in maintaining the phocid mother-pup bond during lactation. For vocal recognition to function, the caller must produce individually distinct calls that are recognised by their intended recipient. Mother-pup vocal recognition has been studied extensively in colonial otariids and appears to be characteristic of this family. Although less numerous, empirical studies of phocid species have revealed a range of recognition abilities. This study investigated whether Weddell seal (Leptonychotes weddellii) females produce individually distinct 'pup contact' calls that function during natural pair reunions. Fifteen calls from each of nine females recorded in the Vestfold Hills, Antarctica were analysed. One temporal, nine fundamental frequency and five spectral characteristics were measured. Results of the cross-validated Discriminant Function Analysis revealed that mothers produce individually distinct calls with 56% of calls assigned to the correct individual. The probability of achieving this level of discrimination on novel data by chance alone is highly improbable. Analysis of eight mother-pup reunions recorded near McMurdo Sound, Antarctica further demonstrated that these 'pup contact' calls function during natural pair reunions. Behavioural analysis also revealed that pups were chiefly responsible for establishing and maintaining close contact throughout the reunion process. Our study therefore demonstrates that Weddell seal females produce calls with sufficient stereotypy to allow pups to identify them during pair reunions, providing evidence of a functioning mother-pup vocal recognition system.Column A - Row 1: Gives the tag number of the female.- Rows 3-33: The list of acoustic measurements recorded from the spectrograms.- Rows 3-5: Temporal measurements recorded in milliseconds.- Rows 7-12: Frequency measurements recorded from the fundamental frequency. Rows 9-11 were measured at the 1/4, 2/4 and 3/4 temporal positions along the fundamental frequency respectively.- Rows 13-17: Give the number of the frequency band with the most energy at the temporal positions stated (i.e. fundamental frequency band=1, first harmonic=2 etc).- Rows 19-29: List the fundamental frequency measurements, taken at the temporal positions stated, used to calculate Mean frequency (Row 31) and the Coefficient of Frequency Modulation (Row 33) using the formula listed in the publication.- Rows 35 and 36: List the cursor error margins of the acoustic analysis program I used.Columns B-P - Give details of the above mentioned acoustic characteristics for 15 replicate calls from each of the 9 females sampled.

以下为所附论文的摘要内容：
声音识别可能是哺乳阶段维持海豹科（Phocidae）母子纽带的关键因素。要实现声音识别功能，发声个体必须发出具备个体特异性的鸣叫声，且能被目标接收者识别。群居海狮科（Otariidae）物种的母子声音识别已被广泛研究，且该特征似乎是海狮科的典型特性。尽管针对海豹科物种的实证研究数量较少，但已有研究揭示了其多样的识别能力。本研究旨在探究威德尔海豹（Leptonychotes weddellii）雌性个体是否会发出具备个体特异性的“幼崽联络鸣叫声”，且该鸣叫声在自然的母子重聚过程中发挥作用。研究分析了在南极洲韦斯特福尔希尔斯（Vestfold Hills）地区录制的9只雌性威德尔海豹的各15次鸣叫声样本，共测量了1项时域特征、9项基频（fundamental frequency）特征以及5项频谱特征。交叉验证判别函数分析（Discriminant Function Analysis）结果显示，雌性个体发出的鸣叫声具备个体特异性，有56%的鸣叫声被正确归类至对应的个体。仅通过随机概率在全新数据上达到该判别准确率的可能性极低。对南极洲麦克默多湾（McMurdo Sound）附近录制的8次母子重聚场景的分析进一步证实，这类“幼崽联络鸣叫声”确实在自然重聚过程中发挥功能。行为分析还显示，在整个重聚过程中，幼崽主要负责建立并维持紧密的身体接触。因此，本研究证明威德尔海豹雌性个体发出的鸣叫声具备足够的刻板性，能够让幼崽在重聚过程中识别出母体，这为运作良好的母子声音识别系统提供了实证依据。

A列第1行：记录雌性个体的标记编号。
第3至33行：从声谱图中提取的声学测量指标列表。
第3至5行：以毫秒为单位记录的时域测量值。
第7至12行：从基频提取的频率测量值。其中第9至11行分别对应基频时域上1/4、2/4和3/4位置的测量结果。
第13至17行：记录指定时域位置上能量最高的频带编号（即基频频带=1，一次谐波=2，依此类推）。
第19至29行：列出在指定时域位置获取的基频测量值，用于按照论文中给出的公式计算平均频率（第31行）和频率调制系数（第33行）。
第35至36行：记录本次研究使用的声学分析软件的光标误差范围。
B至P列：详细记录本次采样的9只雌性个体各15次重复鸣叫声的上述声学特征参数。