Under MacOS Sierra (10.12.2), I:
(1) installed Anaconda 4.2.0 with its default python 3.5.2 root.environment;
(2) with “condo create -n py27 python-2.7 anaconda spyder” created a python 2.7 environment.
(3) use “source activate py27” so as to use that secondary environment,
(4) in Terminal: "(py27) [me:~]$ spyder”
When spyder opens, it’s using the root python 3.5.2 environment, not the python 2.7 environment.
How use python 2.7 environment from spyder under Anaconda?
I note that if, still having activated the py27 environment, I run Anaconda-Navigator.app, then it does not even show spyder among the available IDEs.