Definition

1. Proper noun:
   • A German biologist and a key founder of modern genetics: August Friedrich Leopold Weismann was a 19th and early 20th-century scientist whose work fundamentally shaped the field of heredity. He is best known for his theory of the germ plasm, which proposed that genetic information is transmitted only via germ cells (eggs and sperm), not through somatic (body) cells. This theory explicitly ruled out the inheritance of characteristics acquired during an organism's lifetime.

Usage Examples

• Proper noun:
  • The work of August Friedrich Leopold Weismann provided a crucial argument against Lamarckian ideas of inheritance.
  • In the history of biology, August Friedrich Leopold Weismann is celebrated for his germ-plasm theory.

Advanced Usage

• "Weismann's barrier": A concept in biology derived from his theories, describing the separation between the germline (cells that give rise to gametes) and the soma (the rest of the body's cells). This barrier implies that genetic changes in somatic cells cannot be passed to offspring.

  • The principle of Weismann's barrier is a foundational concept in modern evolutionary biology.

• "Weismannian" (adjective): Pertaining to the theories or ideas of August Weismann.

  • The experiment provided Weismannian evidence against the inheritance of acquired traits.

Variants and Related Words

• Weismann (noun): A common shortened reference to August Friedrich Leopold Weismann.
  • Weismann's influence on genetics is profound.

Synonyms

• Biologist: A scientist who studies living organisms.
• Geneticist: A specialist in genetics (though this term post-dates much of his work, his contributions are foundational to the field).

Related Terms and Concepts

• Germ-plasm theory: Weismann's specific theory of heredity.
• Neo-Darwinism: The modern synthesis of Darwin's theory of evolution by natural selection with Mendelian genetics; Weismann's work is a key pillar of this synthesis.
• Lamarckism: The theory of inheritance of acquired characteristics, which Weismann's work directly contested.

Noun

1. German biologist who was one of the founders of modern genetics; his theory of genetic transmission ruled out the possibility of transmitting acquired characteristics (1834-1914)