Blank Makes Us Uniquely Human

To answer the question humans as a species would first need to agree on what it is to be human, and that'll never happen. Identities and views of life are too diverse (and often deeply irrational). For all that, googling the phrase "makes us uniquely human" turns up a bunch of answers:

"logical thinking" - Terrence Real

"laughter" - Greg Thomas

"an insatiable thirst to know and explore the unknown" - Yasha Husain

"the ability to reproduce tempo and turn it into music" - Dolora Zajick

"thinking" - Donald C. Storm

"[how] the mind is set up in all kinds of organic and experiential ways to sort and select, edit and remember or discard" - Prokofy Neva

"our dualism: our understanding that there are material objects, or bodies, and people, or souls" - paraphrasing Paul Bloom

"language" - Ian Stewart and Jack Cohen

"the right prefrontal cortex" - Donald Stuss

"our ability to imagine the future" - D T Brookes

"our individuality - the ability to go consciously against the 'herd'" - Geoffrey Falk

"the capacity for thought and collective debate and action." - Eva Cox

"our capacity for self-awareness" - Jim Dryden

"transcendent longing to escape from nature" - Peter Lawler

"capacity for a loving relationship with our Heavenly Father" - Center Point Society

"ability for complex imitation" - Beth Azar

"[revealed by] the small differences between our genome and those of other animals" - Svante Pääbo

"early human prehistory" - Bob Gleichauf

"our ability to communicate" - Jan-Michelle Sawyer

"passion and spirit" - Pb Fisher

"the tension between mind and body" - Laurie Hassold

"our ability to add personal perspective to all things" - Gina Lawton

"poker" - Ask Kate

"[a] complex emotional repertoire" - Professor Solomon