The closer other animals are to us evolutionarily the better we feel about them.
Figure 1. Experimental procedure. Based on a focused question,
each evaluator had 22 pairs of pictures to evaluate (randomly drawn
from a total of 52 species). The question, also randomly drawn at
the beginning of the test, was intended to assess either empathic or
compassionate prefernces. Photos by A. Miralles; Source: A.
Miralles, Creative Commons
New research answers critical questions in the study of human-nonhuman animal relationships
A recent paper published in Scientific Reports by Aurélien Miralles,
Michel Raymond & Guillaume Lecointre called "Empathy and compassion toward
other species decrease with evolutionary divergence time" caught my
attention, and I'm glad it did. I found it to be fascinating, methodically
sound, and rich in thought. Each time I read it I think of more questions
about future research in the ever-growing transdisciplinary area called
anthrozoology that focuses on the study of human-nonhuman animal (animal)
relationships. I also think many veterinarians will be interested in this
seminal research.
When I saw the title I immediately thought of Melanie Joy's Why We Love
Dogs, Eat Pigs, and Wear Cows: An Introduction to Carnism (in which the
emphasis is on so-called "farmed animals") and Hal Herzog's Some We Love,
Some We Hate, Some We Eat: Why It's So Hard to Think Straight About Animals.
It also reminded me of an interview I conducted with Kristof Dhont and
Gordon Hodson about their unique book titled Why We Love and Exploit
Animals: Bridging Insights from Academia and Advocacy.
The research essay, which is available for free online, provides a much more
detailed evolutionary (ultimate) explanation than the above sources, which
focus more on proximate, or immediate reasons, why we view different animals
differently and make inconsistent choices about how we interact with them
and use them. For example, why do some people "unmind" cows, pigs, sheep,
chickens, and other animals who they choose to eat, while they fully
recognize that dogs and other companion animals are sentient, feeling
beings, who care what happens to themselves? In fact, they're all mammals
who share the same basic neurophysiology and neural anatomical structures
that are important in how they experience the same emotions in similar ways.
It's essential to remember that cows, pigs, and sheep who are unrelentingly
tortured on factory farms are no less sentient than companion dogs or cats.
The evolutionary biology behind the reasons we view different
animals differently
For the most part, "Empathy and compassion toward other species decrease
with evolutionary divergence time" is a pretty easy read and one can get a
lot out of it by reading the introduction, looking at the accompanying
figures (some of which are included below), and reading the discussion.
To introduce their essay, Aurélien Miralles and his colleagues begin,
"Currently the planet is inhabited by several millions of extremely
diversified species. Not all of them arouse emotions of the same nature or
intensity in humans. Little is known about the extent of our affective
responses toward them and the factors that may explain these differences."
To learn more about why differences in compassion and empathy exist, the
researchers conducted an online survey involving 3509 respondents who had to
answer questions about their "empathic perceptions or their compassionate
reactions toward an extended photographic sampling of organisms."
Participants viewed 47 animal species including humans, four plants, and one
fungi. Of the 3509 raters, 2347 were used in the final sample (1134 for the
empathy test and 1213 for the compassion test).
It's important to understand precisely how this research was carried out and the definitions that were used, I quote directly from their essay. To conduct their study, the researchers write, "The notion of empathy is presently referring to the capability to connect with one another at an emotional level14,17. The driven question proposed to the raters to assess their empathic preferences was 'I feel like I’m better able to understand the feelings or the emotions of [choice among a pair of pictures representing different organisms]'. In contrast, the notion of compassion (also termed empathic concern) has been used here to refer to the feeling of concern for the suffering of others, associated with a motivation to help13,18,19. The corresponding question proposed to raters was “If these two individuals were in danger of death, I will spare the life of [choice among a pair of pictures] as a priority” (Fig. 1). (My emphases; numbers refer to references in the essay.)
Figure 2. Empathy and compassion scores attributed to each organisms as
a function of divergence time (Mya) between them and humans. The scores
correspond to the probability that a given species is chosen from a pair of
species that includes it and another randomly selected (n = 52 species). See
SI Appendix, Results S1 for details. (Illustrations by A. Miralles).
Source: A. Miralles, Creative commons
The results of this novel analysis are pretty straightforward (see Figure
2). Concerning empathy, the correlation between empathy scores and the
divergence time separating the animals from humans was strongly negative.
Likewise, compassion scores were highly correlated with empathy scores and
divergence time (see figure 4). However, the correlation with divergence
time was lower for compassion scores when compared with empathy scores, with
the compassion scores being more related to a person's ethical position on
nonhuman animals. They stress, however, that the close relationship between
the two scores is important.
What does this all mean? Evolutionary and neurobiological
explanations of speciesism
To conclude, the researchers title their discussion "Empathy, resemblance,
and relatedness: The anthropomorphic stimuli hypothesis." They write: "Based
on our results, we here hypothesize that our ability, real or supposed, to
connect emotionally with other organisms would mostly depend on the quantity
of external features that can intuitively be perceived as homologous to
those of humans. The closer a species is to us phylogenetically, the more we
would perceive such signals (and treat them as anthropomorphic stimuli), and
the more inclined we would be to adopt a human to human-like empathic
attitude toward it." (For a related discussion, see "Anthropomorphism Favors
Coexistence, Not Deadly Domination.")
I look forward to furthering the discussion of this landmark paper and
future research on this interesting and important topic. Often, people are
hard-pressed to explain why they feel closer to some nonhumans than to
others, and this essay opens the door to learning more about these
differences. In an increasingly human-dominated world, it's essential to
know why humans feel the way they do about the nonhumans with whom we share
our magnificent planet. Research in anthrozoology surely will help to
provide important and relevant information.