Extras

    Video thumbnail: Nature The clever way the tiniest bird warms her nest

    Nature

    The clever way the tiniest bird warms her nest

    This bird may not be big enough to cover all her eggs, but she can still keep them warm.

    The clever way the tiniest bird warms her nest

    Video thumbnail: Nature How an Egg Hatches

    Nature

    How an Egg Hatches

    See the remarkable way hatchlings are able to break out of their eggs.

    How an Egg Hatches

    Video thumbnail: Nature The Egg: Life’s Perfect Invention Preview

    Nature

    The Egg: Life’s Perfect Invention Preview

    Join Sir David Attenborough to reveal the incredible egg, piece by piece.

    The Egg: Life’s Perfect Invention Preview