comparable ages for the independent origins of electrogenesis in african and south american weakly electric fishes年龄相仿的独立起源在非洲和南美产电弱电鱼.pdf

Comparable Ages for the Independent Origins of Electrogenesis in African and South American Weakly Electric Fishes ´ ´ 1,2 3 4 5 6 Sebastien Lavoue *, Masaki Miya , Matthew E. Arnegard , John P. Sullivan , Carl D. Hopkins , Mutsumi Nishida2 1 Institute of Oceanography, National Taiwan University, Taipei, Taiwan, 2 Atmosphere and Ocean Research Institute, The University of Tokyo, Chiba, Japan, 3 Department of Zoology, Natural History Museum Institute, Chiba, Japan, 4 Human Biology Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America, 5 Cornell University Museum of Vertebrates, Ithaca, New York, United States of America, 6 Department of Neurobiology and Behavior, Cornell University, Ithaca, New York, United States of America Abstract One of the most remarkable examples of convergent evolution among vertebrates is illustrated by the independent origins of an active electric sense in South American and African weakly electric fishes, the Gymnotiformes and Mormyroidea, respectively. These groups independently evolved similar complex systems for object localization and communication via the generation and reception of weak electric fields. While good estimates of divergence times are critical to understanding the temporal context for the evolution and diversification of these two groups, their respective ages have been difficult to estimate due to the absence of an informative fossil record, use of strict molecular clock models in previous studies, and/or incomplete taxonomic sampling. Here, we examine the timing of the origins of the Gymnotiformes and the Mormyroidea using complete mitogenome sequences and a parametric Bayesian method for divergence time reconstruction. Under two different