Max Kleiber (4 January 1893–5 January 1976) was a Swiss agricultural biologist, born and educated in

Zürich Zurich (; ) is the list of cities in Switzerland, largest city in Switzerland and the capital of the canton of Zurich. It is in north-central Switzerland, at the northwestern tip of Lake Zurich. , the municipality had 448,664 inhabitants. The ...

, Switzerland. Kleiber graduated from the Swiss

Federal Institute of Technology ETH Zurich (; ) is a public university in Zurich, Switzerland. Founded in 1854 with the stated mission to educate engineers and scientists, the university focuses primarily on science, technology, engineering, and mathematics. ETH Zurich ran ...

as an Agricultural Chemist in 1920, earned the ScD degree in 1924, and became a '' Privatdozent '' after publishing his thesis, ''The Energy Concept in the Science of Nutrition''. Kleiber joined the Animal Husbandry Department of the

University of California, Davis The University of California, Davis (UC Davis, UCD, or Davis) is a Public university, public Land-grant university, land-grant research university in Davis, California, United States. It is the northernmost of the ten campuses of the University ...

(UC Davis) in 1929 to construct

respiration chambers Respiration may refer to: Biology * Cellular respiration, the process in which nutrients are converted into useful energy in a cell ** Anaerobic respiration, cellular respiration without oxygen ** Maintenance respiration, the amount of cellul ...

and conduct research on energy metabolism in animals. Among his many important achievements, two are especially noteworthy. In 1932, he came to the conclusion that the ¾ power of body weight was the most reliable basis for predicting the

basal metabolic rate Basal metabolic rate (BMR) is the rate of energy expenditure per unit time by endothermic animals at rest.. In other words it is the energy required by body organs to perform normal It is reported in energy units per unit time ranging from watt ( ...

(BMR) of animals and for comparing nutrient requirements among animals of different sizes. He also provided the basis for the conclusion that total efficiency of energy utilization is independent of body size. These concepts and several others fundamental for understanding energy metabolism are discussed in Kleiber's book, ''

The Fire of Life ''The'' is a grammatical article in English, denoting nouns that are already or about to be mentioned, under discussion, implied or otherwise presumed familiar to listeners, readers, or speakers. It is the definite article in English. ''The ...

'', published in 1961 and subsequently translated into German, Polish, Spanish, and Japanese. He is credited with the description of the ratio of metabolism to body mass, which became

Kleiber's law Kleiber's law, named after Max Kleiber for his biology work in the early 1930s, states, after many observations that, for a vast number of animals, an animal's Basal Metabolic Rate scales to the power of the animal's mass. More precisely : posi ...

. Kleiber's law is the observation that, for the vast majority of animals, an animal's

metabolic rate Metabolism (, from ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run cellular processes; the co ...

scales to the power of the animal's mass. More recently, Kleiber's law has also been shown to apply in

plants Plants are the eukaryotes that form the kingdom Plantae; they are predominantly photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars f ...

, suggesting that Kleiber's observation is much more general.

Books

1961: The Fire of Life: An Introduction to Animal Energetics

Awards

1954 Guggenheim Fellowship for Natural Sciences (US & Canada), in

Molecular and Cellular Biology ''Molecular and Cellular Biology'' is a biweekly peer-reviewed scientific journal covering all aspects of molecular and cellular biology. It is published by the American Society for Microbiology and the editor-in-chief is Peter Tontonoz (Universi ...

References

External links

* 1893 births 1976 deaths University of California, Davis faculty 20th-century Swiss biologists ETH Zurich alumni {{biologist-stub