Ministry of Education Key Laboratory for Ecology of Tropical Islands, Key Laboratory of Tropical Animal and Plant Ecology of Hainan Province, College of Life Sciences, Hainan Normal University, Haikou 571158, China.
Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
J Acoust Soc Am. 2021 Feb;149(2):819. doi: 10.1121/10.0003359.
Ontogenetic development of hearing sensitivity has been verified in many groups of vertebrates, but not turtles. Turtles exhibit sexual dimorphism in hearing. To examine the development of hearing in female turtles, auditory brainstem responses (ABR) were compared by assessing the hearing-sensitivity bandwidth, ABR threshold, and latency of female Trachemys scripta elegans aged 1 week, 1 month, 1 yr, and 5 yr. The hearing-sensitivity bandwidths were 0.2-1.1, 0.2-1.1, 0.2-1.3, and 0.2-1.4 kHz in each age group, respectively. Below 0.6 kHz, the ABR threshold decreased from the 1-week to 1-yr age group, with a significant difference between age groups. No significant difference was detected between the 1- and 5-yr age groups (within a stimulus frequency of 0.2-0.6 kHz). Above 0.6 kHz, ABR thresholds decreased significantly from the 1-yr to 5-yr age group (within a stimulus frequency of 0.7-1.0 kHz). There was no significant difference between the 1-month and 1-yr age groups (within a stimulus frequency of 0.7-1.0 kHz), or between the 1-week and 1-month age groups (within a stimulus frequency of 0.7-1.0 kHz, except 0.9 kHz). Thus, female turtle hearing shows frequency-segmented development.
听觉敏感性的个体发生发育在许多脊椎动物群体中得到了验证，但海龟除外。海龟的听觉存在性别二态性。为了研究雌性海龟的听觉发育，通过评估拟穴青龟的听觉脑干反应（ABR），比较了 1 周龄、1 月龄、1 龄和 5 龄雌性拟穴青龟的听力敏感性带宽、ABR 阈值和潜伏期。在每个年龄组中，听力敏感性带宽分别为 0.2-1.1、0.2-1.1、0.2-1.3 和 0.2-1.4 kHz。在 0.6 kHz 以下，ABR 阈值从 1 周龄到 1 龄龄组降低，年龄组之间存在显著差异。在 1 龄和 5 龄年龄组之间未检测到差异（在 0.2-0.6 kHz 的刺激频率内）。在 0.6 kHz 以上，ABR 阈值从 1 龄龄组到 5 龄龄组显著降低（在 0.7-1.0 kHz 的刺激频率内）。在 1 月龄和 1 龄龄组之间（在 0.7-1.0 kHz 的刺激频率内），或在 1 周龄和 1 月龄龄组之间（在 0.7-1.0 kHz 的刺激频率内，除了 0.9 kHz），没有显著差异。因此，雌性海龟的听觉表现出频率分段发育。
