Mutation Theory Short Note | Evolution Class 12 Notes

In this article we will discuss about Mutation Theory of evolution :- Experiments of hugo de vries
and Evidence of mutation theory

• Hugo de Vries proposed the mutation theory of evolution in 1901
• Mutation is sudden change occurring in the genetic material
• According to him, new species are not formed by continuous variations but by sudden appearance of variations

Experiments of Hugo de vries

• He conducted his experiments on Oenothera lamarckiana plant
• He self-pollinated O.lamarckiana and seeds were allowed to grow
• F1 Generation: Majority similar to parents but a few were different plants
• Different plants were also self-pollinated and seeds were allowed to grow
• Next generation majority similar to parents but a few were still more different plants
• It happened generation after generation
• These plants appeared to be new species
• He suggested from his experiments that new species are formed in single step suddenly without any intermediate stage

Evidence of Mutation Theory

• ANCON SHEEP: Short legged variety of sheep which appeared suddenly in England in 1791.
  The breed was artificially selected and maintained for its desirable inability to jump over fences.
• Hornless Cattle developed as mutation from the homed cattle in 1889
• Hairless cats have developed through mutations