Please explain 'if and how' and how paraphrase it

Question

Please explain 'if' and how paraphrase it.

Now, researchers aim to learn if and how animals can really enjoy their lives.

Answer 1

That form is collapsing two statements into one:

They aim to learn if animals have fun.

They aim to learn how animals have fun.

It is usually expressed as follows, so as not to make the how-clause a foregone conclusion:

They aim to learn if, and if so, how animals have fun.