Evolution Commons^™

Disentangling Sentience From Developmental Plasticity, Jonathan Birch

Animal Sentience

Plants, like animals, display remarkable developmental plasticity, inviting the metaphorical use of terms like “decision” and “choice”. In the animal case, this is not taken to be evidence of sentience, because sentience is a complex product of development, not something that guides it. We should apply the same standards when evaluating the evidence in plants. It is hard to overstate the contrast with the case of invertebrates such as octopuses, where pain markers that were originally developed for use in mammals have been clearly demonstrated and plausible neural substrates for sentience have been identified.

Plant Sentience: "Feeling" Or Biological Automatism?, Andrea Mastinu

Animal Sentience

Sentience refers to the ability of an organism to have subjective experiences such as sensations, emotions and awareness. Whereas some animals, including humans, are widely recognized as sentient, the question of whether plants are sentient is still debated among scientists, philosophers, and ethicists. Over the past 20 years, many scientists such as Trewavas, Baluška, Mancuso, Gagliano, and Calvo have reported interesting discussions about memory, behavior, communication, and intelligence in plants. However, the reported conclusions have not convinced the entire scientific community. In this commentary, I would like to focus on two critical aspects related to sentience: cognition and emotion

"In The Beginning, God Created Atoms", Samiya L. Henry

Undergraduate Research and Scholarship Symposium

Genesis 1:1 states “In the beginning, God created the heavens and the earth.” This is the defining statement in the Bible and acts as the foundation of creation and God’s power in the Christian faith. On the other hand, many scientists believe the Big Bang Theory and the discoveries made in other fields of science solely define the creation of the universe and explain life as we know it, also disproving the Christian creation story and the overall existence of God. However, the exact opposite is true; God is science.

Alone, neither of these concepts (faith and science) fully solve …

What Can Plant Science Learn From Animal Nervous Systems?, Luiz Pessoa

Animal Sentience

I welcome Segundo-Ortin & Calvo’s (2023) call for a rigorous science of plant behavior and physiology. My commentary addresses three points drawn from the literature on animal brains that could help elucidate the possibility of cognition and sentience in plants: (1) the presumed requirement of a centralized brain; (2) centralization of control versus heterarchical organization; and (3) connecting plant research with research on animal nervous systems.

Plants Detect And Adapt, But Do Not Feel, Paul C. Struik

Animal Sentience

Plant sentience is a hot topic in scientific and popular media. There are moral reasons to respect both the service of plants to humanity and their natural integrity as creatures playing their own significant role in a complex ecosystem. However, to infer that plants have certain cognitive capacities that are present also in certain human and nonhuman animals calls for scientific rigor beyond mere analogy. The unique capacities of plants identified by Segundo-Ortin & Calvo are not necessarily linked to sentience. Nor is it likely that sentience is an evolutionary trait that is present to some extent in all living …

Insentient “Cognition”?, Stevan Harnad

Animal Sentience

A sentient state is a state that it feels like something to be in. Cows have them, cars don’t. Cognitive capacities are a subset of behavioral capacities. Not all behavioral capacities are cognitive (but the distinction is fuzzy). Might the difference have something to do with whether the behaver is sentient?

Between Choice And Compulsion: An Examination And Critique Of The Evolution Of 'Original Sin', Matthew James Wynn

Graduate Theses/Dissertations

“Why are we the way that we are?” is one of the hardest questions to answer because it requires grasping the origin of human beings. This has left philosophers and theologians in century-long debates on forming a “cosmogony of ontology” (i.e., how the origin of the universe informs the human condition). The concept, “original sin” was developed by a North African theologian named Augustine (354 – 430 CE). Augustine’s reading of Genesis 3, and inaccurate translation of Romans 5:12, taught that a person is born morally culpable for a fault antecedent to their existence. This way of thinking about the …

Plant Sentience Revisited: Sifting Through The Thicket Of Perspectives, Paco Calvo, Miguel Segundo-Ortin

Animal Sentience

In our target article (Segundo-Ortin & Calvo 2023), we proposed the intriguing possibility of plant sentience, drawing parallels with non-human animal studies. This response aims to sift through the rich thicket of perspectives offered by our commentators. To do so, we assess the risks of employing double standards, as well as the tendencies of anthropomorphizing and zoomorphizing in plant studies. We also emphasize the need for clarity in linguistic and conceptual terms, examine the neurophysiological evidence for plant sentience, and discuss the ethical implications of such recognition.

Plant Sentience? Between Romanticism And Denial: Science, Miguel Segundo-Ortin, Paco Calvo

Animal Sentience

A growing number of non-human animal species are being seriously considered as candidates for sentience, but plants are either forgotten or explicitly excluded from these debates. In our view, this is based on the belief that plant behavior is hardwired and inflexible and on an underestimation of the role of plant electrophysiology. We weigh such assumptions against the evidence to suggest that it is time to take seriously the hypothesis that plants, too, might be sentient. We hope this target article will serve as an invitation to investigate sentience in plants with the same rigor as in non-human animals.

The Biological Influence Of Stories & The Importance Of Reading Fiction, Elise N. Good, Katharine Schaab

The Kennesaw Journal of Undergraduate Research

Fictional narratives and stories have persisted throughout human history. However, perhaps due to a bias that stories offered nothing more than entertainment for the reader or perhaps that they are not useful outside of the realm of academia, the research within science academia has been lacking in literature on why these narratives have endured. Unfortunately, due to the lack of conversation across disciplines, particularly those of science and literature, this subject has not been thoroughly investigated through an interdisciplinary lens. Within this paper, the goal is to analyze the benefits of fictional narratives through biological, evolutionary, and neuropsychological perspectives. Research …

Alfred Russel Wallace Notes 21: Wallace & The Doorway To The Universe, Charles H. Smith

Faculty/Staff Personal Papers

An important yet largely unrecognized theme in the thought of Alfred Russel Wallace (1823−1913) was his insistence that all dependably-reported phenomena, even those of aberrant nature, were worthy of a respectful kind of attention: that is, a kind which did not automatically banish difficult subjects to the realm of myth or superstition. In this work, Wallace’s philosophy in this direction is documented, and linked to the world of post-Age-of-Enlightenment revisionism.

Pain Sentience Criteria And Their Grading, Eva Jablonka, Simona Ginsburg

Animal Sentience

On the basis of the target article by Crump and colleagues, we suggest a more parsimonious scheme for evaluating the evidence for sentience. Since some of the criteria used by Crump et al. are not independent and some are uninformative we exclude some criteria and amalgamate others. We propose that evidence of flexible learning and prioritization, in conjunction with relevant data on brain organization, is sufficient for assigning pain-sentience to an animal and we suggest a scoring scheme based on four criteria.

Truly Minimal Criteria For Animal Sentience, Mark Solms

Animal Sentience

The criteria for determining animal sentience proposed in the target article are sensible but they lack an explicit functional justification for the focus on pain. This commentary provides an abbreviated account of the most basic functional principles that underpin animal sentience and articulates some minimal criteria for determining its presence.

Generalizing Frameworks For Sentience Beyond Natural Species, Michael Levin

Animal Sentience

Crump et al. (2022) offer a well-argued example of an essential development: a rigorous framework for assessing sentience from the perspective of moral concern over an agent’s welfare. Current and forthcoming developments in bioengineering, synthetic morphology, artificial intelligence, biorobotics, and exobiology necessitate an expansion and generalization of this effort. Verbal reports (the Turing Test) and homology to human brains are utterly inadequate criteria for assessing the status of novel, unconventional agents that offer no familiar touchstone of phylogeny or anatomy. We must develop principled approaches to evaluating the sentience of (and thus, our responsibility to) beings of unfamiliar provenance and …

Sentience In Decapods: An Open Question, Mark Briffa

Animal Sentience

Crump et al.’s framework is a powerful tool designed to assist decisions on the ethical treatment of decapod crustaceans. However, the question of whether decapods are sentient (i.e., whether they feel), remains open, perhaps indefinitely. More optimistically, we might design experiments that distinguish among different levels of awareness, sometimes viewed as components of sentience. We should strike a balance between assuming that all organisms are sentient and making unnecessary anatomical assumptions about sentience. Refining current experiments may provide concrete insights about awareness in Decapoda and other taxa.

Does The Sentience Framework Imply All Animals Are Sentient?, Kristin Andrews

Animal Sentience

The eight criteria proposed in Crump et al.’s framework for evaluating pain sentience in decapod crustaceans are just the tip of the iceberg when it comes to markers that could increase confidence in an animal’s sentience more generally. Some of the commentaries have already pointed out that pain is only one kind of sentience (Souza Valente). It has also already been pointed out that there are other criteria for pain that could be usefully added to the framework’s eight (Burrell). This expansive thinking about criteria that can be used to increase confidence in sentience raisess the question: in an expansive …

Distinguishing Epistemic And Moral Grounds For Legal Protection, Carlos Montemayor

Animal Sentience

The criteria proposed by Crump et al. are based on various cognitive roles associated with sentience. A subset of them may be sufficient for certain kinds of welfare, but the presence of all of them should be considered as clearly sufficient for substantial kinds of legal protection based on their relation to capacities that we consider essential for moral standing in human beings.

Pain In Pleocyemata, But Not In Dendrobranchiata?, Gary Comstock

Animal Sentience

Crump et al.’s contribution to assessing whether decapods feel pain raises an important question: Is pain distributed unevenly across the order? The case for pain appears stronger in Pleocyemata than in Dendrobranchiata. Some studies report pain avoidance behaviors in Dendrobranchiata (Penaeidae) shrimp, but further studies are needed to determine whether the chemicals used are acting as analgesics to relieve pain, or as soporifics to reduce overall alertness. If the latter, the most farmed shrimp species may not require the same level of protection as crabs, crayfish, and lobsters.

Sentience As Part Of Emotional Lives, Frans B. M. De Waal

Animal Sentience

It is high time to explore the sentience of invertebrate animals, but this topic cannot be discussed without also exploring their emotional lives, including positive emotions. Sentience probably evolved to allow the regulation of emotions by endowing them with feelings.

Decapod Sentience: Promising Framework And Evidence, Jon Mallatt, Todd E. Feinberg Md

Animal Sentience

Strong points of the target article by Crump et al. are that it offers clear criteria for judging whether decapods are sentient, an effective semi-quantitative grading system for this purpose, and an astute, critical review of the literature. It concludes plausibly that major subgroups of decapods are sentient. A minor problem is that it includes classical, Pavlovian learning as a marker of sentience along with the more valid marker of complex (e.g., operant) learning. Another minor problem is that it does not distinguish results that are negative because of likely absence of sentience from results that are negative because they …

Integrating Evolution Into The Study Of Animal Sentience, Walter Veit

Animal Sentience

Like many others, I see Crump et al. (2022) as a milestone for improving upon previous guidelines and for extending their framework to decapod crustaceans. Their proposal would benefit from a firm evolutionary foundation by adding the comparative measurement of life-history complexity as a ninth criterion for attributing sentience to nonhuman animals.

Animal Sentience Research: Synthesis And Proposals, Andrew Crump, Heather Browning, Alex Schnell, Charlotte Burn, Jonathan Birch

Animal Sentience

Most commentaries on our target article broadly support our approach to evaluating evidence of animal sentience. In this Response, we clarify the framework’s purpose and address criticisms of our criteria. A recurring theme is that a framework to synthesise current evidence of sentience is not the same as an agenda for future directions in animal sentience research. Although future directions are valuable, our framework aims to evaluate existing evidence and inform animal welfare legislation.

Time To Stop Pretending We Don’T Know Other Animals Are Sentient Beings, Marc Bekoff

Animal Sentience

Rowan et al.’s target article is an outstanding review of some of the history of the science of sentience, but one would have liked to see a much stronger “call to action.” We don’t need any more data to know that many other animals are sentient beings whose lives must be protected from harm in a wide variety of contexts. It is not anti-science to want more action on behalf of other animals right now.

Sentience In Decapod Crustaceans: A General Framework And Review Of The Evidence, Andrew Crump, Heather Browning, Alex Schnell, Charlotte Burn, Jonathan Birch

Animal Sentience

We outline a framework for evaluating scientific evidence of sentience, focusing on pain experience. It includes eight neural and cognitive-behavioural criteria, with confidence levels for each criterion reflecting the reliability and quality of the evidence. We outline the rationale for each criterion and apply our framework to a controversial sentience candidate: decapod crustaceans. We have either high or very high confidence that true crabs (infraorder Brachyura) satisfy five criteria, amounting to strong evidence of sentience. Moreover, we have high confidence that both anomuran crabs (infraorder Anomura) and astacid lobsters/crayfish (infraorder Astacidea) meet three criteria—substantial evidence of sentience. The case is, …

Of Course Crustaceans Are Sentient: But There's More To The Story, Arthur S. Reber, Frantisek Baluska, William B. Miller Jr.

Animal Sentience

We are in basic agreement with Crump et al. that animal welfare, particularly with regard to the experience of pain, is a topic of importance. However, we come to the issue from a different perspective, one in which all species are sentient and can feel pain. The implications of this theory are discussed.

Defending Human Difference By Raising The Bar, Joe Gough

Animal Sentience

Chapman & Huffman (C&H) offer a theory of why we humans want to believe that we are different: to justify our cruelty to animals. This commentary offers further supporting evidence of this and examines more closely what the claim that humans are ‘different’ amounts to. It also considers some methodological issues in animal psychology closely related to C&H ‘s theory. These problems result from a common strategy for defending hypotheses about human difference.

Sentience Politics : A Fishy Perspective, Culum Brown

Animal Sentience

The plight of fishes has almost certainly got worse since Bentham (1789) coined the phrase “The question is not Can they reason? nor, Can they talk? but Can they suffer?” Despite the fact that fishes are increasingly recognised as sentient animals worthy of protection under animal welfare legislation in many countries around the world, fishing practices are almost universally exempt activities. The human population continues to grow, and, surprisingly, per capita intake of fish is still increasing (FAO 2020). The source of this fish is not wild stocks (catches of which have remained more or less stagnant for …

Legal Recognition Of Animal Sentience: The Case For Cautious Optimism, Jane Kotzmann

Animal Sentience

Rowan et al.’s target article provides a valuable indication of the work that was required to reach the point where animals are recognised as sentient in various laws. To ensure this work was not in vain, the language of sentience needs to be used as a moral currency to demand further cultural change involving greater human respect for animals.

All Living Organisms Are Sentient, Arthur S. Reber, Frantisek Baluska, William B. Miller Jr.

Animal Sentience

We argue that all living organisms, from the simplest unicellular prokaryotes to Homo sapiens, have valenced experiences—feelings as states of preference—and are capable of cognitive representations. Bacteria can learn, form stable memories, and communicate, hence solve problems. Rowan et al.'s statement that "Subjective feelings are just that — subjective — and are available only to the animal (or human) experiencing them" is true but irrelevant. When we see a fish flopping about in the bottom of a boat we immediately recognize suffering without having a glimpse of the nature of piscine distress. Some controlled anthropomorphism can go a …

The Science Of Animal Sentience And The Politics Of Animal Welfare Should Be Kept Separate, Marian Stamp Dawkins

Animal Sentience

Although linked historically by Rowan et al., the scientific study of animal sentience and political campaigns to improve animal welfare should be kept separate, for at least two reasons. First, the separation makes it clear that standards of evidence acceptable for ethical or political decisions on animal welfare can be lower than those required for a rigorously scientific approach to animal sentience. Second, it helps to avoid confirmatory bias in the form of giving undue weight to results that are in line with pre-conceived ideas and political views.