Updated Origin of Turtles video on YouTube

This update
to the original Origin of Turtles YouTube video documents the dual origin of turtles (PDF avaialble on Resarchgate.net) that was not covered in the earlier video, now deleted. This hypothesis was recovered from the large reptile tree (LRT) which now tests 1612 taxa (subset Fig. 2). Other that the turtles themselves, the rest of the included taxa (from birds to fish) are all competing to be the closest outgroup(s) to the turtles. All other candidate taxa, like Eunotosaurus and Pappochelys, are tested in the LRT and featured in the video.

This is a seven-minute video
unfortunately with another eleven minutes of black soundless screen tacked on at the end. Not sure how that happened, but there you are. I would have attempted a repair, but YouTube does not permit identical or near identical videos to be uploaded.

If you want to learn more
about the dual origin of turtles by reading an academic paper on the subject, click this link to ResearchGate.net.

Figure 3. Subset of the large reptile tree (LRT, 1199 taxa) with the addition of three basal turtles

Figure 2. Subset of the large reptile tree (LRT, 1612 taxa) focusing on basal turtles

Abstract from The Dual Origin of Turtles from Pareiasaurs
“The origin of turtles (traditional clade: Testudines) has been a vexing problem in paleontology. New light was shed with the description of Odontochelys, a transitional specimen with a plastron and teeth, but no carapace. Recent studies nested Owenetta (Late Permian), Eunotosaurus (Middle Permian) and Pappochelys (Middle Triassic) as turtle ancestors with teeth, but without a carapace or plastron. A wider gamut phylogenetic analysis of tetrapods nests Owenetta, Eunotosaurus and Pappochelys far from turtles and far apart from each other. Here dual turtle clades arise from a clade of stem turtle pareiasaurs. Bunostegos (Late Permian) and Elginia (Late Permian) give rise to dome/hard-shell turtles with late-surviving Niolamia (Eocene) at that base, inheriting its Baroque horned skull from Elginia. In parallel, Sclerosaurus (Middle Triassic) and Arganaceras (Late Permian) give rise to flat/soft-shell turtles with Odontochelys (Late Triassic) at that base. In all prior phylogenetic analyses taxon exclusion obscured these relationships. The present study also exposes a long-standing error. The traditional squamosal in turtles is here identified as the supratemporal. The actual squamosal remains anterior to the quadrate in all turtles, whether fused to the quadratojugal or not.”

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