Shahandeh Michael P, Brock Cameryn, Turner Thomas L
Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, Santa Barbara, CA, United States of America.
PeerJ. 2020 Jul 16;8:e9499. doi: 10.7717/peerj.9499. eCollection 2020.
Differences in courtship signals and perception are well-known among species. One such described difference is the dependency on light, and thus presumably vision, for copulation success. Many studies have described a difference in light-dependent copulation success between and , identifying as a light-dependent species, and as a light-independent one. However, many of these studies use assays of varying design and few strains to represent the entire species. Here, we attempt to better characterize this purported difference using 11 strains of each species, paired by collection location, in behavioral assays conducted at two different exposure times. We show that, while there is a species-wide difference in magnitude of light-dependent copulation success, copulation success is, on average, still impaired in the dark at both exposure times we measured. Additionally, there is significant variation in strain-specific ability to copulate in the dark in both species across two different exposure times. We find that this variation correlates strongly with longitude in , but not in . We hypothesize that differences in species history and demography may explain behavioral variation. Finally, we use courtship assays to show that light-dependent copulation success in one strain is driven in part by both males and females. We discuss potential differences in courtship signals and/or signal importance between these species and potential for further comparative studies for functional characterization.
求偶信号和感知方面的差异在物种间是众所周知的。一种已被描述的差异是交配成功对光的依赖性，因此推测也依赖视觉。许多研究描述了[物种A]和[物种B]在光依赖性交配成功方面的差异，将[物种A]鉴定为光依赖性物种，[物种B]为非光依赖性物种。然而，这些研究中有许多使用了不同设计的试验，且仅用少数菌株来代表整个物种。在这里，我们试图通过对每个物种的11个菌株进行更好的特征描述，这些菌株按采集地点配对，在两个不同的光照时间进行行为试验。我们表明，虽然在光依赖性交配成功的程度上存在全物种差异，但在我们测量的两个光照时间下，[物种A]的交配成功率在黑暗中平均仍会受损。此外，在两个不同光照时间下，两个物种在黑暗中交配的菌株特异性能力都存在显著差异。我们发现这种差异在[物种A]中与经度密切相关，但在[物种B]中并非如此。我们推测物种历史和种群统计学的差异可能解释行为上的变化。最后，我们使用求偶试验表明，一个[物种A]菌株的光依赖性交配成功部分是由雄性和雌性共同驱动的。我们讨论了这些物种在求偶信号和/或信号重要性方面的潜在差异，以及进行功能特征进一步比较研究的潜力。
