Complex sentence: The course evolved without the help of any one architect for many years, though notable contributions to its design were made by Daw Anderson in the 1850s and Old Tom Morris (1865--1903), who designed the 1st and 18th holes.
Split into simpler sentences: The course evolved without the help of any one architect for many years. However, the more significant people to its design were Daw Anderson in the 1850s and Old Tom Morris (1865--1903) who designed the 1st and 18th holes.