Final answer:
Barbara McClintock was the first scientist to discover transposable elements, also known as transposons, while studying maize genetics.
Step-by-step explanation:
The scientist who was the first to discover transposable elements in any system and coined the term 'transposition' was Barbara McClintock. This groundbreaking discovery was made while she was working on maize genetics during the 1940s and 1950s. McClintock identified a breakage event on chromosome 9 in maize, which she referred to as the dissociation locus (Ds). She also discovered the activator locus (Ac), which could trigger the Ds chromosome to break. The elements that could change their position within the genome are now known as transposons or 'jumping genes.' McClintock's findings were initially met with skepticism, but were later confirmed with the discovery of transposons in other organisms like bacteriophages, bacteria, and Drosophila, highlighting the existence and importance of these genetic elements in various forms of life.