1
|
Chen B, Mao T, Liu Y, Dai W, Li X, Rajput AP, Pie MR, Yang J, Gross JB, Meegaskumbura M. Sensory evolution in a cavefish radiation: patterns of neuromast distribution and associated behaviour in Sinocyclocheilus (Cypriniformes: Cyprinidae). Proc Biol Sci 2022; 289:20221641. [PMID: 36476002 PMCID: PMC9554722 DOI: 10.1098/rspb.2022.1641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Accepted: 09/22/2022] [Indexed: 02/07/2023] Open
Abstract
The genus Sinocyclocheilus, comprising a large radiation of freshwater cavefishes, are well known for their presence of regressive features (e.g. variable eye reduction). Fewer constructive features are known, such as the expansion of the lateral line system (LLS), which is involved in detecting water movements. The precise relationship between LLS expansion and cave adaptation is not well understood. Here, we examine morphology and LLS-mediated behaviour in Sinocyclocheilus species characterized by broad variation in eye size, habitat and geographical distribution. Using live-staining techniques and automated behavioural analyses, we examined 26 Sinocyclocheilus species and quantified neuromast organ number, density and asymmetry within a phylogenetic context. We then examined how these morphological features may relate to wall-following, an established cave-associated behaviour mediated by the lateral line. We show that most species demonstrated laterality (i.e. asymmetry) in neuromast organs on the head, often biased to the right. We also found that wall-following behaviour was distinctive, particularly among eyeless species. Patterns of variation in LLS appear to correlate with the degree of eye loss, as well as geographical distribution. This work reveals that constructive LLS evolution is convergent across distant cavefish taxa and may mediate asymmetric behavioural features that enable survival in stark subterranean microenvironments.
Collapse
Affiliation(s)
- Bing Chen
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, People's Republic of China
- Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Institute of Biodiversity Science, Center of Evolutionary Biology, School of Life Sciences, Fudan University, Shanghai 200438, People's Republic of China
| | - Tingru Mao
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, People's Republic of China
| | - Yewei Liu
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, People's Republic of China
| | - Wenzhang Dai
- School of Life Science and Institute of Wetland Ecology, Nanjing University, Nanjing 210000, People's Republic of China
| | - Xianglin Li
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, People's Republic of China
| | - Amrapali P. Rajput
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, People's Republic of China
| | - Marcio R. Pie
- Biology Department, Edge Hill University, Ormskirk, Lancashire L39 4QP, UK
| | - Jian Yang
- Key Laboratory of Environment Change and Resource Use, Beibu Gulf, Nanning Normal University, Nanning, Guangxi, People's Republic of China
| | - Joshua B. Gross
- Department of Biological Sciences, University of Cincinnati, Cincinnati OH 45221, USA
| | - Madhava Meegaskumbura
- Guangxi Key Laboratory for Forest Ecology and Conservation, College of Forestry, Guangxi University, Nanning 530004, People's Republic of China
| |
Collapse
|