The models created by the preparator Alfred Keller (1902-1955, Berlin) remain among the pinnacles of arthropod model-building.
A scientific model-maker, Keller was employed by the Museum from 1930 until his death. During this time, he created a plethora of biological models. His works have remained an international benchmark to this day.
Keller first modelled his objects in clay and then made plaster casts on which he worked meticulously. The final model was a negative cast in paper maché. Early plastic materials (celluloid and galalith/erinoid) were used for wings and bristles and then attached to the model. He finished off his models using gold leaf and painting for the right colour effects. Such meticulous, detailed work was labour and time-intensive and it took nearly a year to complete the fly model.