The evolution and physiology of male pregnancy in syngnathid fishes

@article{Whittington2020TheEA,
  title={The evolution and physiology of male pregnancy in syngnathid fishes},
  author={Camilla M. Whittington and Christopher R. Friesen},
  journal={Biological Reviews},
  year={2020},
  volume={95}
}
The seahorses, pipefishes and seadragons (Syngnathidae) are among the few vertebrates in which pregnant males incubate developing embryos. Syngnathids are popular in studies of sexual selection, sex‐role reversal, and reproductive trade‐offs, and are now emerging as valuable comparative models for the study of the biology and evolution of reproductive complexity. These fish offer the opportunity to examine the physiology, behavioural implications, and evolutionary origins of embryo incubation… 
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TLDR
Understanding the changes associated with the parallel evolution of male pregnancy in the two major syngnathid lineages will help to identify key innovations that facilitated the development of this unique form of reproduction and, through comparison with other forms of live bearing, may allow the identification of a common set of characteristics shared by all viviparous organisms.
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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