There is evidence that critiques the use of NHA (Non-Human Animal) studies
Sentience
The ability to perceive or feel things
Self-awareness
The ability to recognize oneself as an individual separate from the environment and other individuals
Animals feel pain but this may not be the same as conscious awareness
Gallup (1970) demonstrated that chimpanzees have self-awareness
Chimpanzees were introduced to mirrors, red marks were placed on their foreheads and ears, and they would touch the marks using the mirror to direct their response
This clearly demonstrates that animals have self-awareness and therefore are sentient
In December 2009 the Treaty of Lisbon, which governs the European Union, declared that all animals are sentient
Some human beings have a lack of sentience, such as brain damaged patients and infants
We would not use them in research without consent, suggesting NHA research is problematic
