The individual known for developing the principles of heredity is Gregor Mendel, an Austrian monk and scientist. In the mid-19th century, Mendel conducted experiments using pea plants to study the inheritance of traits. His work led to the formulation of foundational concepts in genetics, such as the laws of segregation and independent assortment. Although his research went largely unrecognized during his lifetime, it later gained prominence and laid the groundwork for modern genetics. Mendel's principles have had a profound impact on biology, influencing our understanding of heredity, evolution, and the mechanisms behind genetic variation in organisms.