Final answer:
Galaxies likely evolved from matter clustering around dark matter 'seeds' in the early universe, with stars forming within these clumps. Spiral galaxies can evolve into elliptical galaxies through interactions and mergers. Elliptical galaxies are often the end result of these evolutionary processes.
Step-by-step explanation:
The evolution of galaxies is a complex and dynamic process, influenced by both the initial conditions present at the galaxy's birth and its subsequent interaction with its environment.
The prevailing view in astronomy suggests that galaxies formed early in the universe's history, following the birth of stars. As fluctuations in the Cosmic Microwave Background Radiation (CMBR) coalesced around dark matter 'seeds', matter began to clump together, eventually leading to star formation and the genesis of galaxies.
One of the more likely evolutionary paths of a galaxy is the transformation of spiral galaxies into elliptical galaxies. This can occur through the merging of smaller galaxies or through interactions that strip away or disrupt the spiral structure, causing the galaxy to become more spherical and less structured over time.
As for the formation from other galaxy types, spiral galaxies can develop from the merger of smaller, irregular galaxies in an environment rich in interstellar gas and matter that can form new stars and galactic disks. A spiral structure forms as the galaxy rotates and the differential gravitational forces create distinct arms.
When considering the most likely result of these processes, an elliptical galaxy is often the end state for many galaxies, particularly in dense galactic clusters where interactions and mergers are more common, resulting in the loss of a defined structure that spirals possess.