Consciousness: What is consciousness? Check out my Consciousness: From the Soul to the Abyss for an answer. The following is a reasonable timeline of the likely evolution of the traits needed for consciousness. This view demonstrates how consciousness evolved over billions of years. Since we share these consciousness traits with other animals, with the exception of convergent evolution, we can use Occam’s Razor to determine the ancestral source of traits. For those interested in a step-by-step exploration of this process, “Researching Evolutionary Traits: The Occam Approach” provides an in-depth look at the methodology.
Consciousness
Touch: Life Learns to Feel Force
~3.72 Billion Years Ago (after prokaryotes)
Mechanical sensitivity to pressure and membrane stretch
Presentient Animals Emerge: The Ediacaran Prelude
635-600 Million Years Ago
Proto-brain; Pre-brain memory; Presentient.
Chemoreception: Taste and Smell Emerge
600 Mya
Vision Emerges: The Pre-fish Chordates
540 Mya
Vision Emerges; Proto-Simple Brains; Pre-vertebrate Cord.
Simple Sentience Settles: Haikouichthys
520 Million BCE
Simple Brains; Proto-Short-Term Memory; Simple Sentience.
Long-Term Memory Evolves: Tiktaalik
375 Mya
Complex Brains; Long-Term Memory; Simple Sentience.
Land Hearing Emerges: Amphibians
370 Mya
Land Hearing Emerges; Yet Larger Brains.
Early Complex Sentience Emerges: Dimetrodon
295 Million BCE
Complex Brains; Long-Term Memory; Early Complex Sentience.
Early Play Evolves in Mammals
190 Million Years Ago (+/- 10 million years)
Parental care, brain plasticity, extended juvenile period
Complex Sentience Settles: Eomaia scansoria
circa 125 Million BCE
Complex Brains; Long-Term Memory; Complex Sentience; Likely Proto Self-aware.
Higher Play Evolves in Social Mammals
80 Million Years Ago (+/- 10 million years)
Enlarged neocortex
Early Self-Awareness: Miacis
50 Million BCE
Territory memory, where things are, hippocampus development
Early Intelligence Emerges: Aegyptopithecus zeuxis
30 Million BCE
Complex Brains; Long-Term Memory; Complex Sentience; Semi Self-awareness settles in.
Genus Proconsul (Self-Awareness Settles)
20 Million Year Ago (+/- 2 Million Years)
Complex Brains; Long-Term Memory; Complex Sentience; Maybe Self-aware; Likely Simple EI.
Great Apes: Medicine Emerges
18 Million Years Ago, ± 3 million years
Causal reasoning, Early prefrontal integration
Genus Kenyapithecus: EI Emerges
Lived 16 to 14 Million Years Ago
Prefrontal–limbic integration, Reading others, Modulating reaction
Laughter Emerges
14.5 Million Years Ago (+/- 2 million)
Limbic vocalization pathways, Breath control
Genus Dryopithecus: Cultural Transmission Emerges
Emerged 13 mya, extinct 9 to 7 mya
Cultural Transmission
Collective Learning Emerges
3.3 Million Years Ago
Homo habilis: Our Intelligence Settles.
2.3 Million BCE
First Proto-Containers
2 Million Years Ago
Emergence of Early Hominin Shelters
1.8 Million Years Ago (+/- 500,000 years)
Hyoid Bone: Speach Emerges
700,000 BCE
Full Emotional Intelligence Emerges
700,000 Years Ago
Transcendental Intelligence Emerges
475,000 Years Ago
Homo neanderthalensis: Verified True Symbolic Thought
430,000 BCE
On Earth from 430,000 to 29,000 BCE
Homo Sapiens: Advanced Transcendental Intelligence
315,000 BCE