How did the ancient galaxies observed by the HST in deep views differ structurally from modern, well-defined galaxies?

The ancient galaxies captured often appeared irregular, clumpy, and smaller, suggesting ongoing formation or merging.

By observing galaxies at great distances, the HST effectively acts as a time machine, showing objects as they existed billions of years ago when the universe was much younger. A key difference noted by astronomers is structural evolution. While modern galaxies generally appear as well-defined structures, the light collected from these ancient systems shows that they were frequently irregular, clumpy, and relatively smaller. This morphology suggests that these galaxies were still in earlier stages of cosmic history, actively involved in mergers and gravitational interactions that would eventually lead to the more organized structures seen in the present-day universe.