Use npm ls to list installed packages and see the dependency graph of a given package eg:
> npm ls core-js
my_module /path/to/my_module>
└─┬ pug@2.0.4
└─┬ pug-code-gen@2.0.2
└─┬ constantinople@3.1.2
└─┬ babel-types@6.26.0
└─┬ babel-runtime@6.26.0
└── core-js@2.6.10