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Lamarck, Jean-Baptiste

Botanist 1744-1829

Jean-Baptiste Lamarck was born on August 1, 1744, in Bazentin-le-Petit, France. He died on December 18, 1829. He is best known for his theory on evolution, which stated that acquired traits can be inherited. Charles Darwin later challenged this theory. Lamarck also was the first scientist to define animals as either vertebrates (having backbones) or invertebrates (those without).

Lamarck came from a long line of military horsemen. At the age of nineteen he left a school run by Jesuits (a religious order) to join the army. While serving he became interested in the plants along the Mediterranean Sea. Resigning from the army after an injury, Lamarck began to study medicine, but then switched his interest to botany. He studied under the French botanist Bernard de Jussieu at the royal botanical gardens in Paris. After years of studying and collecting, he published a three-volume work on the plants of France in 1778. This gained him recognition, and in 1781 he was put in charge of the royal gardens in Paris.

In the 1790s Lamarck changed his interest from plants to animals and soon developed a system for classifying invertebrates. He appears to have been the first scientist to relate fossils to the living creatures to which they are most similar. When the Museum National d'Histoire Naturelle was founded in 1793, Lamarck was placed in charge of the invertebrates. Lamarck was one of the founders of the modern concept of the museum collection.

From his studies on plants and animals, Lamarck developed his theory of evolution. He believed that plants and animals change their forms to adapt to their environment, and that their young inherit these changes. He thus believed, for example, that the forelegs and necks of giraffes have become longer due to the way they eat. These acquired traits would be passed on to following generations. Lamarck presented his ideas in the famous Philosphie Zoologique (1809). His theory, not unreasonable for its time, was later disproved by discoveries in genetics in the early 1900s and rejected by most scientists. However, the Soviet Union embraced Lamarck's theory in the Stalin era. This set that nation back in genetics until the 1960s.

Another area of interest for Lamarck was the weather. He was the first scientist to try to forecast it. He published an annual weather report from 1799 to 1810. He is believed to have named the various types of clouds: cirrus, stratus, cumulus, and nimbus.