A groundbreaking study reveals that red-footed tortoises experience long-term mood states.
Researchers specializing in animal behavior and cognition at the University of Lincoln have uncovered new evidence about reptile sentience that could lead to major changes in how these animals are managed in captive environments.
Their groundbreaking study presents strong evidence that red-footed tortoises (Chelonoidis carbonaria) are capable of experiencing lasting mood states, much like mammals and birds. This finding represents a significant advancement in our understanding of reptile subjectivity, challenging traditional beliefs and carrying important consequences for animal welfare practices.
Testing optimism and pessimism in tortoises
The researchers worked with 15 red-footed tortoises, applying a cognitive bias test originally designed for use in humans. This method helps reveal whether an individual interprets ambiguous situations with optimism or pessimism, depending on their underlying emotional state.
Widely used in studies of mammals and birds, the test offers insight into how animals perceive uncertainty, serving as an indirect measure of mood. The team discovered that tortoises living in enriched environments were more likely to interpret ambiguous cues positively, indicating a more optimistic and possibly happier state of mind.
To further explore this connection, the researchers also assessed the tortoises’ responses to anxiety-inducing situations, such as encountering unfamiliar objects and environments. Tortoises that made more optimistic judgments during the cognitive bias test also showed fewer signs of anxiety, strengthening the evidence for a relationship between emotional state and behavior.
These findings contribute to a growing body of research suggesting that reptiles may possess a more sophisticated emotional life than previously assumed. While reptiles are already recognized for their learning and problem-solving skills, this study offers the clearest indication yet that they can experience enduring mood states—a central feature of sentience.
Implications for animal welfare laws
Understanding whether animals can experience moods and emotions is crucial for informing welfare standards. In the UK, the Animal Welfare (Sentience) Act 2022 recognizes the capacity of animals to feel, which directly influences how they are treated under the law.
Anna Wilkinson, Professor of Animal Cognition at the University of Lincoln, explained: “Animal welfare concerns are reliant upon evidence that a given species has the capacity to experience affective states. With reptiles becoming increasingly common as pets, it is essential for us to study their moods and emotions to try to understand how captivity may impact them.”
Oliver Burman, Professor of Animal Behavior and Welfare at the University of Lincoln, added: “This is an exciting finding that represents a significant shift in our understanding of what reptiles can experience, with important implications for how we care for these animals in captivity and interact with them in the wild.”
The findings also offer new insights into the evolution of affective states, i.e. emotions and moods, across species. If reptiles, a group that diverged from mammals and birds hundreds of millions of years ago, can experience moods, it suggests that affective states may be more widespread in the animal kingdom than previously believed.
Reference: “Evidence of mood states in reptiles” by Tatjana Hoehfurtner, Anna Wilkinson, Sophie A. Moszuti and Oliver H.P. Burman, 28 June 2025, Animal Cognition.
DOI: 10.1007/s10071-025-01973-y
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12 Comments
Thank you for your contributions! What’s the news for learning open mindset!
I am always welcome for learning news scitech daily, thank you.
It always surprises me that people are surprised that animals have feelings and emotions, as if humans are so unique, that we’re the only ones that have them đź‘€ it should be assumed that all animals have them–pretty sure even insects do. Anything that has behaviour, has cognition and emotions.
Human exceptionalism is likely a function of culture. Some cultures show more respect towards animals. Other cultures believe that animals were put on earth by the good lord to serve humans. At least we have moved away from the idea that some humans were put on earth to serve some other humans as slaves – though that change happened only a short time ago relative to the length of human history.
Animals are living things, everything alive feels.
Ridiculous! There’s a reason that elephants are widely called “soft-shelled turtles.” We’ve known for hundreds of years that neither animal has emotions, feelings or nervous systems capable of experiencing pain. Can’t believe people will entertain such rubbish!
I’m pretty sure that none of that is true…
My apologies, it seems you’re correct!
So quick to dismiss, suggests arrogant ignorance !
What you’re saying absolutely isn’t true. Elephants, for example, have been seen grieving the dead. Though they do travel they’ve been observed being saddened when they come back to the spot where the elephant died.
Also to say tortoises have no emotions is clearly false. I have had two tortoises and have talked to others in my tortoise group. They can be scared, relaxed, curious, even angry. They can also feel pain. I remember once when someone trimmed their tortoise’s beak too short in one spot. That tortoise was wary of anyone touching their face and had trouble eating.
Is the sentence in last paragraph correct: “If reptiles, a group that diverged from mammals and birds hundreds of millions of years ago…”? Birds and mammals originates from reptiles. Maybe the sentence should be: “If reptiles, [a group much older than / predecessors of] mammals and birds …” Correct me if I’m wrong.
We know some human and other mammals emotions originate in the reptilian complex of the brain. Those emotions are then rendered to consciousness which exists in the mammalian complex. Reptiles, and lower on the tree of life organisms, lack the mammalian complex and are thus unable to experience emotions the same way mammals do.
Think in terms of a frog having a leg bitten of by a predator and then several minutes later is sitting on the lily pad catching insects. Clearly it isn’t experiencing pain like a mammal. Or a mammal having extensive surgery and totally unaware of the experience as the mammalian parts of the brain were chemically turned off.