Mr Mawson's fossils

Abstract

Abstract Joseph Mawson, a nineteenth-century British railway engineer and businessman in Brazil, discovered fossils from the Cretaceous of Bahia that were described by E. D. Cope and Arthur Smith Woodward. A biographical outline of Mawson is presented. Mawson's discoveries (especially the giant coelacanth fish Mawsonia , named after him by ASW) are interpreted today in the light of modern geological investigations. Mawsonia apparently lived in fluvial, lacustrine and brackish-water habitats in western Gondwana at the time South America separated from Africa. From the Late Jurassic until the Barremian, Mawsonia was widespread across western Gondwana, but its Aptian–Cenomanian records in South America are restricted to northeastern Brazil (including the Borborema tectonic province and adjacent areas to its north). In contrast, Mawsonia remained widespread in the Aptian–Cenomanian of Africa. Recently published data suggest that northeastern Brazil was still contiguous with Africa in the Aptian/Albian, although it was probably separated from the rest of South America by an epicontinental seaway that apparently followed an unconventional course across the Brazilian interior rather than along the present-day coastline. Aptian–Cenomanian records of Mawsonia and other non-marine taxa (including tetrapods) in northeastern Brazil may therefore represent ‘African’ rather than ‘South American’ biotas.