Die Sammlungen (The Collections)

Hamburger Bahnhof Museum für Gegenwart, Berlin. Until 6 February 2011.

Venturing upstairs in Berlin's Museum für Gegenwart (Museum for Contemporary Art), we enter a darkened space inhabited by alien creatures, eerily spotlit in glass cases.

The specimens in the exhibition, Die Sammlungen (The Collections), exude an air of menace. As we look more carefully, we begin to recognize some of the monsters as familiar insects, most obviously Musca domestica, the common housefly, and Pulex irritans, the flea, immortalized in Robert Hooke's Micrographia of 1665. The models, enlarged by a factor of 100, recall Hooke's comment about the terrible wonder of such magnified insects. He described the flea he viewed down his microscope as “adorn'd with a curiously polish'd suit of sable Armour, neatly jointed, and beset with multitudes of sharp pinns, shap'd almost like Porcupine's Quills, or bright conical Steel-bodkins”.

One of the large models on display is as bizarre a creature as we might ever see. It looks like a cartoon beetle with some ultra-sensitive receiving device of spheres and tendrils mounted on a short mast protruding from its back. It is in fact Bocydium globulare, the most extravagant of the leaf hoppers (pictured). The hollow globes, like the remarkable excrescences exhibited by other leaf hoppers, probably deter predators.

Credit: HWA JA GÖTZ, MFN BERLIN

This model is by the brilliant sculptor, Alfred Keller (1902–55). Keller was trained as a kunstschmied, an 'art blacksmith'. From 1930 until his early death he was employed by the Berlin Museum für Naturkunde (Museum of Natural History), painstakingly labouring over his recreations of insects and their larvae. Each took a year to complete.

Keller worked first in plasticine, from which he cast a model in plaster. This plaster reference model he then recast in papier maché. Some details he added, cast in wax, with wings and bristles in celluloid and galalith (an early plastic material used in jewellery). Finally he coloured the surfaces, sometimes with additional gilding. The levels of patience and manual control Keller exercised were incredible. His fly, for example, boasts 2,653 bristles.

It may surprise some to find that papier maché — a material now associated with messy child's play — was used in such a refined manner for scientific modelling. It was developed as a serious medium by the anatomist Louis Auzoux of Paris. He was looking for a cheap and portable alternative to the wax models that graced only the best funded schools of medicine. During the 1820s Auzoux perfected his technique, mixing powdered stone and flax fibres into his paper pulp. The resulting models of bodies, with removable parts, were light, strong and flexible, and could be coloured and labelled.

Auzoux set up a factory and shop to manufacture and distribute his models worldwide, progressively extending his production to zoological and botanical examples. His large-scale insects proved especially popular. His shop in the Rue du Medecine in Paris survived into the 1990s; its remaining specimens were auctioned in 1998.

Although they used similar media and sometimes the same insect subjects, Keller and Auzoux stood at different ends of the modelling business. Auzoux produced on a commercial scale; Keller was a sculptor of monumental one-off portraits. Each model is a masterpiece, with no effort spared. It is difficult to see how such a skilled artisan could survive in today's museums, with their emphasis on cost analysis. Keller's exacting models may be things of the past, yet they are far from obsolete. Like the great habitat dioramas, they exercise a magnetic attraction.

Are Keller's models art or science? They are truly both. In the Museum für Gegenwart we tend to see their artistry; in the Museum für Naturkunde their scientific dimension. But Keller's artistry is always apparent in his observations of nature — and his scientific observations are central to his art.