Video clip – William Bateson and patterns of inheritance

This video clip from the BBC TV series Botany: A Blooming History continues the story of the pioneers of genetic research, showing how William Bateson used logic and patience to explain patterns of inheritance, and the ideas of dominant and recessive genes.

William Bateson had read Mendel’s paper on inheritance in pea plants and wanted to know if the ratios held true for other plants and animals. When his team crossed a black cockerel and a black hen they found that some of the chicks were white. When this was repeated, they always had 3 black to one white offspring. Bateson had no knowledge of genes, but used logic to explain the inheritance patterns. Skittles are used to demonstrate the ideas of genes being in pairs and having different forms, some of which can override the influence of others. Bateson went on to find the same pattern of inheritance in other plants and a wide variety of animals.

Introduce the concept of factors or “genes” in the inheritance of characteristics, and the ideas of dominant and recessive genes. Students can then be given experimental data to interpret and develop the skills of showing simple inheritance patterns using punnet squares. They can then identify dominant and recessive characteristics. Discuss how ideas from different sources can contribute to an accumulation of knowledge in science.