VR... in 1961 the band marched 180, one line of tubas, one line of drums, no trombones, NO women. I think the band is now marching 240
Some time in the 1970s they added tether (?) drums, that set of four drums hanging around one drummer's neck and the drum section was well on its way to Hell.
Trombones were added in the 80s I believe.
As for the military style of the uniforms, I much prefer that to the flaming gaucho musketeer look, or the U Texas marching Howdy Dowdys, or the many Napolenoic war costumes any of which are preferable to USC's combination of world war two class A's and a Ben Hur hat. Talk about goofy.
The military style was adopted in the early days of the marching band as one of it's functions was to also preform as a band for military reviews. in the 1950s and 1960s the military band was made up of ROTC students and since every male HAD to take two years of ROTC (or 9 hours of upper level math, science or foreign language) there were plenty of candidates, thus the military band was what we military types call "a purple suit outfit" meaning you wore the uniform of your own branch, Army, Navy or Air Force. Some time in the early 60's the military band cut their own album. They often played at basketball games switching off with the pep band and the university concert band.