Is there any default transpiler and bundler used by node package manager? - reactjs

Question

I'm new to reactJs. I'm using node package manager (NPM) for release, build and hosting process. I first ran npm install -g create-react-app command to install the command whose template helped me in creating a basic reactJs application. Now my package.json file looks like this:
{
"name": "my-react-app",
"version": "0.1.0",
"private": true,
"dependencies": {
"react": "^15.5.4",
"react-dom": "^15.5.4"
},
"devDependencies": {
"react-scripts": "0.9.5"
},
"scripts": {
"start": "react-scripts start",
"build": "react-scripts build",
"test": "react-scripts test --env=jsdom",
"eject": "react-scripts eject"
}
}
If you closely look at both dependencies and devDependencies section you will not be able to find anything like Babel (a transpiler) or webpack (a bundler). So I'm wondering that when I run my website using npn run start command then how my reactJs class files are getting transpiled and bundled. Is there any default transpiler and bundler used by NPM or I'm missing something in my observation?
[Update After Nicholas's comment]:
On a contrary, in a live project code base in which I work in my office, I see that these dependencies like babel-core, babel-cli, webpack etc are mentioned in devDependencies section. They are absent from dependencies section. If react-scripts already have an implicit dependency on babel-core, babel-cli, webpack etc then why do they have to be mentioned explicitly in devDependencies section? Even devDependencies can also simply do so by mentioning react-scripts they way it is happening in my test project. Isn't it? But my fellow developers aren't doing so.

Answer 1

react-scripts, which get's called when you run $ npm start has those transpilers/bundlers as it's own dependencies.
You won't see the dependencies of an explicitly installed module, react-scripts in your example, within your package.json. They would exist as dependencies in react-scripts module's package.json instead.
For example, have a look at the package.json of this subfolder, of that react-scripts module.
It contains a bunch of dependencies, some of them being Babel and Webpack.