The human brain is a hefty thing. It makes you wonder: How exactly did we get to the human brain? Image credit: BBC/Furnace Ltd/Andy JacksonThe social brain theoryAnother key contributor to human intelligence is our sociality. If ape society is complex, then humans took it to a whole new level, which is what’s inspired a theory known as “the social brain theory”. <span class="fr-mk" style="display: none;"> </span><span class="fr-mk" style="display: none;"> </span><span class="fr-mk" style="display: none;"> </span><span class="fr-mk" style="display: none;"> </span><span class="fr-mk" style="display: none;"> </span>"So, it’s not the way that other creatures, like birds, think.