Introgression, hominin dispersal and megafaunal survival in Late Pleistocene Island Southeast Asia

Teixeira, J. C.; Jacobs, G. S.; Stringer, C.; Tuke, J.; Hudjashov, G.; Purnomo, G. A.; Sudoyo, H.; Cox, M. P.; Tobler, R.; Turney, C. S.; Cooper, A.; Helgen, K. M.

doi:10.1101/2020.07.24.219048

bioRxiv · 10.1101/2020.07.24.219048

Introgression, hominin dispersal and megafaunal survival in Late Pleistocene Island Southeast Asia

Teixeira, J. C.·Jacobs, G. S.·Stringer, C.·Tuke, J.·Hudjashov, G.·Purnomo, G. A.·Sudoyo, H.·Cox, M. P.·Tobler, R.·Turney, C. S.·Cooper, A.·Helgen, K. M.

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Abstract

The hominin fossil record of Island Southeast Asia (ISEA) indicates that at least two endemic super-archaic species - Homo luzonensis and H. floresiensis - were present around the time anatomically modern humans (AMH) arrived in the region >50,000 years ago. Contemporary human populations carry signals consistent with interbreeding events with Denisovans in ISEA - a species that is thought to be more closely related to AMH than the super-archaic endemic ISEA hominins. To query this disparity between fossil and genetic evidence, we performed a comprehensive search for super-archaic introgression in >400 modern human genomes. Our results corroborate widespread Denisovan ancestry in ISEA populations but fail to detect any super-archaic admixture signals. By highlighting local megafaunal survival east of the Wallace Line as a potential signature of deep, pre-H. sapiens hominin-faunal interaction, we propose that this understudied region may hold the key to unlocking significant chapters in Denisovan prehistory.

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Teixeira, J. C., Jacobs, G. S., Stringer, C., Tuke, J., Hudjashov, G., Purnomo, G. A., Sudoyo, H., Cox, M. P., Tobler, R., Turney, C. S., Cooper, A., Helgen, K. M.. 2020-07-24. Introgression, hominin dispersal and megafaunal survival in Late Pleistocene Island Southeast Asia. https://doi.org/10.1101/2020.07.24.219048

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