Fantastic Patagonia: Ramon Lista's pangolin, Florentino Ameghino's mysterious mammal, and the carnival parade of the wooden plesiosaur

Abstract

The discovery of megafaunal remains in the “Cueva del Milodón” (Última Esperanza Province, Chile) in 1895 marked a milestone in the knowledge of the South American Pleistocene fauna. The arrival at the Museo de La Plata in 1898 of a fragment of mummified sloth hide from this site, brought by Francisco P. Moreno opened a new chapter in the paleontology of the time. Immediately after this discovery, Florentino Ameghino's publication of “Première Notice sur le Neomylodon listai...” unleashed a widespread furor in the scientific community and society at large by proposing the survival of ground sloths in southern Patagonia. Several unsuccessful expeditions followed during the late 19th century to trap the supposed animal (the “mysterious quadruped”). With the signing of the arbitral award with Chile in 1902, the Última Esperanza region became definitively Chilean territory. Ameghino insisted on information about monstrous beings inhabiting Patagonia. Later, in the early 20th century, letters and rumors that reported sightings of mysterious beings associated with bodies of water in southern Patagonia renewed interest in the supposed survival of extinct beings, promoting an expedition organized by Clemente Onelli in 1922 with the participation of the Museo de La Plata. Although for the general public, this expedition was about hunting a supposed marine reptile, Onelli intended to continue the search for the sloth described by Ameghino. Efforts to find extinct animals in Patagonia continued well into the early 21st century. In this work, we document the effects and the reach of Ameghino's claims, from the 19th to the 21st century, about the existence of ground sloths still living in Patagonia. In addition, we discuss the changes in the perception of prehistoric animal survival, both from academic and public perspectives. In conclusion, we highlight the success of Ameghino in persuading the community of most prominent national and international researchers of the time and the broad public, about the existence of a “mysterious quadruped” living in the southern tip of South America.