Shamanism and psychedelics are central to understanding the evolutionary roots of ecopsychology and its basic principles. The ancient ritual roots of shamanism constituted the context within which psychedelic experiences contributed selective influences to the evolution of human neuropsychology. Both shamanic psychology and ecopsychology involve a neuroepistemology that reflects the neurotransmitter effects of psychedelics on cognition. Shamanism contributed to the development of our ecopsychology through influences on psychological, social and cognitive evolution. Shamanism embodies the concept of animism, the notion of the spiritual essence of all nature which is recognized as the core of the oldest of humanity’s religious beliefs. Shamanism provided the context within which this animistic attitude and the sense of the sentience of the many entities of the world were developed, especially in the relationship to animals. Animal species and their variant qualities provided a natural metaphoric system to structure psychological development and the evolution of social organization. Within the context of shamanism, the worlds of animal species and spirits intertwined in the creation of symbolic potentials for the differentiation of self – embodied in animal spirit powers – and the collective identity of society – embodied in totemic animals. This incorporation of the elements of nature into personal powers and social identity made shamanic ecopsychology a basic feature of human nature and culture.