Reptile Sentience And Why It Matters

One class of animal is largely overlooked by the modern animal advocacy movement and by animal welfare legislation in the western world is reptiles. Though not used frequently for food, some are used for their skins or kept as pets or in zoos. Very little research has been done on the mental faculties of reptiles, who are commonly thought of as less sentient than birds or mammals – the animals generally protected under animal welfare laws. However, what limited research has been done has cast doubt on this assumption; this study examines the evidence for reptile sentience and advanced cognition.

The paper begins by outlining different “levels” of cognition, from the simplest to the most complex. We generally afford all vertebrates some degree of awareness – they are able to modify their behavior in a way that signifies they are aware of their environment and the effects of different phenomena. A smaller subset of animals is known to have some kind of self-awareness: they are aware of themselves as individuals. This can be studied through many methods, such as the famous “mirror test” in which an animal is presented with a mirror and given a mark on a part of their body that they can only see in the mirror. If the animal sees the mark in the mirror and attempts to remove it from their body, they are said to be self-aware.  Only a few species have done this: humans, great apes, bottlenose dolphins, Asian elephants, and European magpies. Other mirror tests, such as using mirrors to find food, have been completed with varying degrees of success by pigs, dogs, octopuses, parrots, and crows. The various species that complete these tests have many things in common. Specifically, they are social animals that also display evidence of empathy, which does not describe the vast majority of reptiles.

Theory of mind — recognizing what you know and how you know it — is a higher level of cognition that is not afforded to many animals. One indicator of this is gaze-following – seeing another being look in a direction and realizing that we should look in that direction as well.  The list of animals that display gaze-following is similar to those who pass the mirror test, with one notable inclusion: the red-footed tortoise. Red-footed tortoises are able to recognize pictures of food as food, as well as solve a novel puzzle after observing a trained tortoise solve it. 

Many people, including reptile breeders and keepers, believe reptiles to be little more than biological machines, incapable of positive experiences like affection and friendship. This belief has led to many people and institutions, from pet owners to zoos, keeping reptiles in habitats that simply have the bare minimum for survival: water, heat, sloughing aids, food, and burrowing material. However, there is some evidence that some reptiles are capable of having emotions and individual personalities. Emydid turtles have demonstrated play behavior, and eastern box turtles, delicate skinks, and Namib rock agamas have all demonstrated various individual levels of boldness, as measured by time spent basking in the open. Three species of tortoises have also demonstrated color preferences, likely based on the colors’ associations with flowering fruit in their native habitat. Experiments with giant tortoises have also found individual preferences in enrichment activities within the population – some prefer shell rubs, others prefer neck rubs, and others prefer food or toys. Clearly, at least some reptiles are capable of having preferences and personalities like other, “higher-order” animals. 

The question, then, is how many species have this capability, and to what extent? The authors do not have the answer to this question and point out that reptiles and amphibians are under-studied animals with regard to cognition and intelligence. They call for more research to be done in this field, as effective animal welfare guidelines depend on having proper information about the capacities and requirements of the animals involved. Preliminary evidence suggests that we are vastly underestimating these animals, and perhaps our welfare guidelines should treat them with more respect. When considering questions of sentience and cognition, it’s important that animal advocates push for research in this area which doesn’t use captive animals or put animals in distress in the wild to draw its conclusions.