Galaxy Zoo: the dependence of morphology and colour on environment*

We analyse the relationships between galaxy morphology, colour, environment and stellar mass using data for over 10⁵ objects from Galaxy Zoo, the largest sample of visually classified morphologies yet compiled. We conclusively show that colour and morphology fractions are very different functions of environment. Both colour and morphology are sensitive to stellar mass. However, at fixed stellar mass, while colour is also highly sensitive to environment, morphology displays much weaker environmental trends. Only a small part of both the morphology-density and colour-density relations can be attributed to the variation in the stellar-mass function with environment.