Why is man a special creature? what two worlds does he share in?

Some would argue that man is not so special; but it's important to realise that as human beings we have a tendency to improve on and dominate a lot of nature and other creatures. This question is (if answered according to the question) is very philosophical and there is no definite way of answering it. 
Man also shares a world with humanity and a world according to the other creatures who inhabit the planet. Some people believe humans to be different from animals and others would say that a human is nothing but a more conscious animal. So the 'worlds' are not necessarily a physical thing, but they do allow us to compare life as an animal and life according to how the majority of humans live it.