Paul Sarasin

His dissertation titled "Die Entwicklungsgeschichte der Bithynia tentaculata" was about the developmental history of a small aquatic snail.

[6] The Sarasins conducted research in various fields within the natural sciences, and they amassed a collection of zoological and geological objects (namely Molluscs).

They later developed interests both in anthropology and ethnology; they photographed and interviewed people, noted measurements of the human body, recorded their language, and collected works of art.

[9] Instead of a sharp line, the Sarasins proposed a zone of gradual change and asked to research about the kind of connections of the land which would explain the existing populations.

Since the island was at this time only loosely controlled by the colonial administration of the Netherlands, they had to travel through mostly unknown areas of the nearly independent kingdoms of Luwu, Sidenreng and Bone.

[13] When Fritz Sarasin travelled, 1910-1911, to the islands of the New Caledonia in the South Pacific, he met there with another ethnologist from Basel, Felix Speiser, who at this time did his research on the New Hebrides.

[15] Along with Hermann Fischer-Sigwart, Jakob Heierli, Albert Heim, Hans Schardt, Carl Schroter, Ernest Wiczek, and Friedrich Zschokke, they were the founders of the Schweizerische Naturschutzkommission (the Swiss Nature Conservation Commission).

Fritz Sarasin and Paul Sarasin during their expedition to Celebes .
In Celebes the Sarasins explored the geographical distribution of certain molluscs to support their theory of a gradual change between regions. Illustration from one of their books.