I would disagree somewhat.
Man is above other earthly creatures. But lower than the angels. What puts us lower than angels is our current organic bodies.
What puts us above the other earthly creatures is the quantum entanglement God imparted upon us and our incorruptible spirit selves.
And that definitely is something which requires a higher intelligence in order to grasp its meaning. However, the actual qualitative difference is not the degree of intelligence, but rather in the possession of knowledge.
We as animals have instincts / learned behaviors / etc. We as humans also possess revealed wisdom regarding good and evil.
More to your point... I say it is a unique characteristic of ours that we do NOT simply do what we do 'for the betterment of the human race'.
But rather for both Higher reasons and lower.
Humans do not have instincts. Humans do have intuition.