The New York Declaration on Animal Consciousness
A scientific statement outlining evidence for conscious experience in a range of nonhuman animals and encouraging serious consideration where evidence is substantial.
Read the declaration ↗A field guide to living systems
Where does biological responsiveness end—and experience begin?
The Sentience Index is a curated guide to the scientific study of animal consciousness, plant signaling, and the many ways living organisms detect and respond to their environments.
Browse the organism registry →Biological systems · Research collection 01
39Organism profiles
04Research collections
2026Current edition
Explore the catalog
Organism registry
Search familiar foods and explore their taxonomy, biological processes, and current scientific evidence.
Try a food name, “shellfish”, “leaf”, “mammal” or “fungi”.
Evidence & interpretation
Responsiveness is not automatically sentience.
Organisms can detect stimuli, transmit signals, and change their behavior without those observations alone establishing conscious experience. The registry distinguishes established evidence, open scientific questions, and editorial case studies. Index determinations are educational classifications created for this project; they do not replace scientific consensus or peer-reviewed findings.
Comparative overview
Evidence at a glance
A qualitative orientation to the current scientific picture—not a numerical score or ranking of species.
Strong support
Mammals & birds
Converging behavioral, neurological and physiological evidence supports conscious experience.
Serious consideration
Fish, cephalopods & decapods
Evidence is substantial in several groups, while confidence and findings vary across taxa.
Uncertain / developing
Bivalves & insects
Evidence differs substantially by group and species; important questions remain open.
Not established
Plants & fungi
Complex signaling is documented, but subjective experience has not been established scientifically.
This overview is deliberately cautious. “Not established” does not mean every question is settled; “serious consideration” does not mean every species has the same evidence profile.
Selected publications
Research library
Foundational scientific sources and selected conceptual case studies examining biological mechanisms.
Research note: The library distinguishes published scientific literature from conceptual case studies developed for this educational index. Case studies are illustrative and are not peer-reviewed publications. Source links are provided for independent review.
The Cambridge Declaration on Consciousness
An influential declaration concerning neural substrates associated with consciousness in humans and nonhuman animals.
Read the declaration ↗Mechanical Injury Signaling in Apple Fruit Tissue
An illustrative research scenario examining wound-response signaling, electrical variation and biochemical changes in fruit tissue. This is a conceptual case study, not a published experiment.
Conceptual case studyEthylene-Mediated Ripening Coordination in Bananas
An illustrative examination of ethylene-regulated ripening, metabolic coordination and plant signaling. This case study is intended to frame questions for discussion, not report experimental findings.
Conceptual case studyElectrical Response Networks in Carrot Root Tissue
An illustrative overview of electrical signaling and coordinated responses in root tissue, grounded in established plant physiology. Electrical activity alone does not demonstrate subjective experience.
Conceptual case studyPlant Consciousness: A Critical Review
A review examining claims about plant consciousness and the distinction between plant responsiveness and conscious experience.
Find the review ↗Decapod Crustacean Sentience
A review of behavioral and physiological evidence relevant to sentience in decapod crustaceans, including crabs, lobsters and shrimp.
Read the review ↗Scientific Declaration on Insect Sentience and Welfare
A scientific statement outlining evidence and open questions concerning insect sentience and welfare.
Read the declaration ↗Cephalopod Sentience: Current Evidence
A recent review of evidence relevant to sentience in cephalopods, including octopuses, squid and cuttlefish.
Find the review ↗