Here's why:

* His groundbreaking experiments: Mendel's work with pea plants in the mid-19th century laid the foundation for our understanding of inheritance. He meticulously tracked traits across generations and formulated the fundamental laws of inheritance: the Law of Segregation and the Law of Independent Assortment.

* His focus on quantitative data: Unlike earlier scientists who observed inheritance patterns qualitatively, Mendel used rigorous quantitative analysis to demonstrate the underlying principles of inheritance.

* His work was largely ignored initially: While Mendel published his findings in 1866, they were not widely recognized until the early 20th century. However, when his work was rediscovered, it revolutionized the field of biology and led to the development of modern genetics.

While Mendel is considered the "father of genetics," it's important to acknowledge that other scientists contributed significantly to the field, both before and after Mendel. These include:

* Charles Darwin: His theory of evolution provided a framework for understanding the role of heredity in the diversification of life.

* Hugo de Vries, Carl Correns, and Erich von Tschermak: These scientists independently rediscovered Mendel's work in the early 1900s, bringing it to the forefront of scientific attention.

* Thomas Hunt Morgan: His work with fruit flies in the early 20th century established the role of chromosomes in heredity.

The development of modern genetics is a complex story with many contributors, but Gregor Mendel's foundational work and the principles he established make him the rightful recipient of the title of "founder."