Index: invoke/runners.py
--- invoke/runners.py.orig
+++ invoke/runners.py
@@ -320,7 +320,7 @@ class Runner(object):
             Default: ``False``.
 
         :param str shell:
-            Which shell binary to use. Default: ``/bin/bash`` (on Unix;
+            Which shell binary to use. Default: ``/bin/sh`` (on Unix;
             ``COMSPEC`` or ``cmd.exe`` on Windows.)
 
         :param timeout: