How to use the reactfire.useFirestoreCollection function in reactfire

const Animals = ({ serverAnimals }) => {
  let initialAnimals = deserialize(serverAnimals);

  let animals = initialAnimals;

  if (firebase.apps.length) {
    animals = useFirestoreCollection(
      firebase.firestore().collection('animals'),
      { startWithValue: initialAnimals }
    );
  }

  return (
    <ul>
      {animals.docs.map(animal =&gt; (
        <li>name: {animal.data().commonName}</li>
      ))}
    </ul>
  );
};