universetoday.com
Big Galaxies, Older Stars
After examining more than 4,000 galaxies in a recent survey, astronomers have discovered that most large galaxies are filled with old stars, It was expected that these large galaxies would be regularly ingesting smaller galaxies, creating bursts of star formation. Instead, however, it's the smaller, fainter galaxies which seem to have all the hot star formation. The large, red galaxies contain the bulk of the mass in the nearby Universe, but very little is understood about their formation or evolution.
Fraser Cain