What mammal has the most complex brain?

While it's difficult to definitively say which mammal has the most complex brain, the human brain is widely considered to be the most complex and sophisticated.

Here's why:

* Size and Structure: The human brain is relatively large compared to body size and has a highly developed neocortex, responsible for higher cognitive functions.

* Neural Density: The human brain has a high density of neurons, allowing for complex neural networks and information processing.

* Cognitive Abilities: Humans exhibit advanced cognitive abilities such as language, abstract thought, problem-solving, and self-awareness, which are supported by the complexity of our brains.

However, it's important to remember that complexity is multifaceted and depends on how you define it. Other mammals, like dolphins and elephants, have large and sophisticated brains with specialized abilities.

Ultimately, measuring and comparing brain complexity across different species is a challenging task, and there's no single metric that can capture all aspects of complexity.