Live birth in the Devonian period

@article{Long2008LiveBI,
  title={Live birth in the Devonian period},
  author={John A. Long and Kate Trinajstic and Gavin Young and Timothy John Senden},
  journal={Nature},
  year={2008},
  volume={453},
  pages={650-652}
}
The extinct placoderm fishes were the dominant group of vertebrates throughout the Middle Palaeozoic era, yet controversy about their relationships within the gnathostomes (jawed vertebrates) is partly due to different interpretations of their reproductive biology. Here we document the oldest record of a live-bearing vertebrate in a new ptyctodontid placoderm, Materpiscis attenboroughi gen. et sp. nov., from the Late Devonian Gogo Formation of Australia (approximately 380 million years ago… 

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TLDR
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TLDR
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ABSTRACT A full description of a complete and articulated, three-dimensionally preserved, placoderm fish, Materpiscis attenboroughi (Ptyctodontida), from the Late Devonian Gogo Formation is

The characters of Palaeozoic jawed vertebrates

TLDR
A clearly stated hierarchy of synapomorphies covering the jaw-bearing stem gnathostomes and osteichthyan and chondrichthyan stem groups is provided and a proposed synapomorphy scheme is used to evaluate the status of the problematic fossil groups Acanthodii and Placodermi.

Terrestrial Origin of Viviparity in Mesozoic Marine Reptiles Indicated by Early Triassic Embryonic Fossils

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The new specimen contains the oldest fossil embryos of Mesozoic marine reptile that are about 10 million years older than previous such records and strongly indicates a terrestrial origin of viviparity, in contrast to the traditional view.

Exceptional preservation of organs in Devonian placoderms from the Gogo lagerstätte.

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Arthrodires show the earliest phylogenetic evidence for repositioning of the gnathostome heart associated with the evolution of the complex neck region in jawed vertebrates.
...

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