Bichir, Polypterus lapradii

Polypterus, Museum of Zoology Cambridge

Roz Wade, Education and Outreach Officer at the Museum of Zoology, writes:

Throughout my time studying Zoology and working at the Museum I’ve had a fondness for quirky animals. Animals with interesting adaptations, peculiar lifestyles, weird and wonderful morphology, or retaining striking primitive characteristics that are lost in their relatives. Polypterus is a fish that fits the bill, and has fascinated me since watching it “waving” its large, round pectoral fins in a fish tank in a museum years ago.

Polypterus is an air-breathing, freshwater fish from Africa. When it was discovered in the early 19th century, naturalists found its classification a challenge – amphibian or fish? Lobe-fin or ray-fin? It is a ray-finned fish (the most diverse group of vertebrates on the planet. If you have a fish that isn’t a lungfish, coelacanth, or cartilaginous fish, you have an actinopterygian), but one that has retained many primitive traits. Take the scales – a thick, bony armour of interlocking rectangles covered in tough, shiny enamel. Although different in detail, this looks very similar to the shiny, enamel-covered scales of the osteolepidid fishes (a group of long-extinct lobe-finned fishes) I have spent many hours studying. Bony scales like these are found in many fossil ray-finned fishes too. Then take a look at the skull – from certain angles the mouth of Polypterus has the appearance of a faint smile about it compared with the down-turned mouth of most ray-fins. Add to this the unusual fins – a row of finlets along the length of the back, and wonderful, round pectoral fins – and you have, for me, an engaging fish. But the fish itself is not the only thing of note about this specimen, as I have been discovering in researching the new displays for the Museum.

This particular specimen was collected by John Samuel Budgett, a Cambridge zoologist and embryologist working around the turn of the 20th century.  Budgett went on four African expeditions, attempting to find the embryos he wanted to understand this peculiar fish and its position within the vertebrate story. Finally, on what would be his last expedition in 1903, Budgett was able to observe the earliest stages of development of Polypterus, of which he produced elaborate drawings. However, he would never present his findings himself. Budgett tragically died in January 1904 at the age of 31 from blackwater fever, a complication of malaria. He was not the only zoologist to lose their life in pursuit of this fish – Nathan Harrington of Columbia University who was searching the Nile for embryos of Polypterus, contracted what was described as Nile Fever in 1899, a disease that was to take his life in a matter of days at the age of just 29. In the new Museum we hope to tell the stories of the people behind the collections, including the hardships and risks they undertook to further our knowledge of the animal kingdom, as well as the fascinating scientific stories of the animals themselves.

(To find out more about the Museum redevelopment, visit the Museum of Zoology website)