Ernst Heinrich Philipp August Haeckel

Ernst Haeckel was a German biologist and philosopher who popularized Charles Darwin's work in Germany. He was a physician and, later, a professor of comparative anatomy at the University of Jena. He was one of the first to consider psychology as a branch of physiology. He also made significant contributions to the fields of marine biology, embryology, ecology, and systematics. He coined many terms in biology, such as ecology, phylum, phylogeny, and Protista. He was an avid artist who produced hundreds of detailed drawings of living organisms, especially radiolarians, sponges, and other marine invertebrates. His most famous work is Kunstformen der Natur (Art Forms in Nature), a book of lithographic and halftone prints that influenced both science and art. He also formulated the recapitulation theory, which states that an individual organism's development repeats the evolutionary history of its species. This theory is often expressed by the phrase "ontogeny recapitulates phylogeny". Although this theory is now considered erroneous, it had a lasting impact on the development of evolutionary thought. Haeckel was also a proponent of monism, a philosophical view that there is only one kind of substance or reality in the universe. He rejected the dualism of mind and matter and believed that nature and God are identical. He founded the Monist League, a German organization that promoted his worldview and advocated for social reform. He was a controversial figure in his time, as he was accused of scientific fraud, racism, and anti-Semitism. He was also criticized by some religious groups for his naturalistic and materialistic views. However, he was also admired by many scientists, artists, and intellectuals for his originality and creativity. He died in 1919 at the age of 85.