order an array of animal names by animal size

function orderBySize($animals)
{
    $sizes = [
        'elephant' => 'large',
        'mouse' => 'small',
        'rabbit' => 'small',
        'dog' => 'medium',
        'leopard' => 'medium',
        'cheetah' => 'medium',
        'lion' => 'large',
        'tiger' => 'large',
        'giraffe' => 'large',
        'rhino' => 'large',
        'hippo' => 'large',
        'zebra' => 'large',
        'wolverine' => 'medium',
        'baboon' => 'medium',
        'cow' => 'large',
        'pig' => 'large',
        'sheep' => 'medium',
        'goat' => 'medium',
        'horse' => 'large',
        'donkey' => 'large',
        'ostrich' => 'large',
        'kangaroo' => 'medium',
        'crocodile' =>