Research Highlight - New Giant Stem Tetrapod Discovered in Gondwana's Late Palaeozoic Ice Age

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In a groundbreaking discovery published online in Nature, researchers have unearthed a new giant stem tetrapod, Gaiasia jennyae, in early Permian-aged deposits in Namibia. This finding challenges existing theories on early tetrapod evolution, as Gaiasia was found in high-palaeolatitude regions of Gondwana, indicating a more widespread distribution of tetrapods during the Carboniferous–Permian transition.

Fig. 1: G. jennyae gen. et sp. nov. (From reference)

Gaiasia jennyae is characterized by its unique features, including a weakly ossified skull, enlarged dentary, and coronoid fangs. Phylogenetic analysis places Gaiasia as the sister taxon of Carboniferous Colosteidae from Euramerica, highlighting its significant position in the tetrapod evolutionary tree.

Fig. 2: Time-calibrated phylogeny (majority-rule consensus tree) of major Palaeozoic and Triassic tetrapod lineages illustrating the relationships of G. jennyae and the evolution of body size. (From reference)

The discovery of Gaiasia in the Huab Basin suggests the existence of stable tetrapod communities at high latitudes, challenging the belief that the region was uninhabitable during the late Palaeozoic glaciation. The gap between known and potential geographical ranges of ancient species is addressed. This finding sheds new light on the diversity dynamics of early tetrapods and underscores the importance of exploring diverse geographical regions for a comprehensive understanding of Earth's ancient ecosystems.

This discovery not only expands our knowledge of tetrapod evolution but also prompts a reevaluation of global tetrapod faunal turnover and dispersal dynamics during this critical transitional period. As researchers continue to uncover fossils from different latitudes, our understanding of early tetrapod evolution is poised to undergo significant transformation.

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REFERENCE

Marsicano, C.A., Pardo, J.D., Smith, R.M.H. et al. Giant stem tetrapod was apex predator in Gondwanan late Palaeozoic ice age. Nature (2024). https://doi.org/10.1038/s41586-024-07572-0