Mendel performed an experiment in which he took a tall plant with round seeds and short plant with wrinkled seeds. In $F_1$ progeny all tall with round seeds were produced. Tallness and roundness were thus dominant traits. When he used these $F_1$ progeny to generate $F_2$ progeny by self-pollination, he found that some $F_2$ progeny, were tall plants with round seeds, while others were short, but had round seeds. Thus Mendel's experiment shows that tall or short traits and round or wrinkled seed traits are independently inherited.