In his 60 years of research, Ewald Weibel has published more than 400 articles and multiple books. He is a holder of the "Swiss Nobel Prize" Marcel Benoist Prize, honorary doctor, pioneer in the field of electron microscopy, established the Institute of Anatomy at the University of Bern as the director, acted as the rector, and made the case for bringing science down from the ivory tower. The American Physiological Society has now honoured his significant contribution to the development of physiology in a video interview. In it, Ewald Weibel talks about his career, his proudest scientific achievements and a good many anecdotes.

The pea experiment

His passion for research was awakened at an early age: at the Aarau cantonal school, which Albert Einstein has attended 50 years earlier – and has never been extinguished. "I have always had a broad range of interests," says Weibel. Although he has spent a lifetime teaching anatomy, he considers himself to be more than a physiologist, he is interested in the interaction of vital process in the organism, and in particular in gas exchange in the alveoli. The number of these alveoli in the human lungs was not yet known at the end of the 1950s because these small structures could only be seen under a microscope in thin slices.

Together with a cardiologist, Weibel was able to present a counting method for determining the number of alveoli in such slices thanks to an experiment using peas inlaid in gelatine: there are around 300 million alveoli in the human lungs. The pea experiment was published in the "Journal of Applied Physiology", one of the best-known journals in this field – "and probably the first time that vegetables were represented in it," Weibel remembers.

In the middle of his scientifically very fruitful stay in the USA, he had to leave the States in 1962 because he had become an "illegal immigrant" upon the expiry of a research grant. Back in Switzerland, he constructed the first electron microscope at the University of Zurich. In 1966, he followed a call to Bern in order to take up the position of director of the Institute for Anatomy there at the age of 37. No easy task, since it was a large institute which nonetheless had no infrastructure for modern research. Weibel's extensive development plans were approved by local government, and he was able to modernise the institute.

"Lungs in the heart" 

Across the decades, his research interest focused in particular on one organ: "I had the lungs in my heart," says Weibel. He was particularly interested in gas exchange and the diffusion capacity, so the maximum ability of human and animal lungs to absorb oxygen, and how this is affected by the structure. In order to determine this with different capacities, he started a project in Kenya, together with a physiologist from Harvard University, in which wild animals were trapped and their lungs and muscles were studied while running on a treadmill.

They were thus able to demonstrate, using 27 animals weighing between half a kilo and 250 kilos, that the ability of the lungs to absorb oxygen increases when the muscle cells need more oxygen while working. This resulted in the theory of symmorphosis, which says that human and animal bodies only "build" as much structure as they need for a function.

"Retain independent thinking!"

Alongside his scientific activities, Weibel was also active on a variety of committees, several times as their president, and acted as the rector of the University of Bern in 1984-85. As such, he was committed to bringing science down from the ivory tower and into society, to which end he founded the academic commission, which became the University and Society Forum in 2002, in collaboration with the university establishment in 1986. When asked what advice he would give to young researchers today, Weibel says: "It takes great effort to retain independent thinking in such a rigidly structured teaching system." He recommends seeing that medicine is a service, but also a science which can improve this service. For discoveries, it is important to recognise weaknesses in the existing system and hang onto them – this can result in great successes: "Retain independent thinking!"