Poor White Mouse
What advises us not to do to others what we do not want to happen to ourselves - that means either Kantian morality or compassion. Can unsuspicious fellow creatures also serve with it?
First, it was mirror images that played the main role in man's self-assurance: no being in our world except humans succeeds in recognizing themselves as me in the mirror - more precisely, almost none. It requires self-awareness and self-reflection; the idea that one's identity is something unique, different from similar ones in the big wide world. In this regard, Homo sapiens leaves almost all of their fellow creatures behind - but annoyingly forms a semi-exclusive, self-confident club in which some species of monkeys and dolphins are still members.
So what else is the difference between humans and animals? Intelligence? Yes, but the borderline between humans and animals certainly also runs in the border area between instincts and feelings, which are only moderately controlled by higher brain functions. There must also be typical emotions that can only be felt by people and close relatives - or, if they are observed in more distant relatives, make them appear surprisingly human. An example: pity. Compassion and empathy are the classic human traits; even if, for example – once again! – Chimpanzees also show approaches that can be interpreted as similar emotions.
Classically human? What the Canadian pain researcher Jeffrey Mogil and his team are now proclaiming in this context sounds like a revolution: The researchers looked for and found the ability for "empathy" in their experiments on test animals that had previously been unsuspicious of any emotion - mice.
The common laboratory rodent, remember the mirror self-recognition test, isn't even one of the animals that have an overt self-awareness - now should he be compassionate? After all, mice are definitely social creatures with a sense of family. And therefore, according to the idea of Mogil and Co, they should also be able to react to the condition of their neighbor in a socially differentiated manner. So Mogil's team gave Mus musculus a chance to prove himself emotionally.
His subjects were recruited from related and unrelated nestmates as well as mice who were strangers to each other, two of which were draped in a test box in different combinations. The couple was always separated by a perforated plexiglass pane, which at least ensured visual and olfactory contact between the two rodent candidates. Then the unsavory part began – pain was inflicted on one or both of the involuntary individuals, such as by an injection of diluted acetic acid.
This is quite painful for a single mouse - which researchers determined, incidentally, from the extent of the mice's reflexive abdominal twitching, a commonly used indicator of pain or, in politely scientific terms, "nociception". But what was exciting for Mogil and colleagues was how rodents react to the pain of conspecifics - and that was very different. Pricked mice, which at the same time had to watch a conspecific that they did not personally know suffer, suffered comparatively even less - which from an anthropocentric point of view could now be described as quite pitiless. But: Acid-plagued mice, which also had to watch an injected mouse they knew from their shared cage times suffer, suffered even more.
Shared sorrow, double sorrow - and all out of pity? Mogil thinks so, given the obvious unequal perception of strangers and familiar fellow sufferers. The experiment also works when rodents who are deaf or deprived of their sense of smell see each other suffer - but not when there is a screen between them. In addition, the longer the animals have been raised together, the stronger the effect. Whether they're related or just familiar doesn't matter, by the way.
For Mogil, the case is thus clear – for others, anything but that. Ultimately, it has only been proven that mice perceive the pain of other mice, distinguish between alien and non-alien conspecifics, and can also combine these two abilities in certain situations. Perhaps the mice only copy what they perceive in social partners - for example, to maintain a certain group behavior. This is certainly not empathy in the usual sense of the word, says behavioral researcher Frans de Waal from Emory University - even if the rodents are "attuned to each other" in a certain sense.
Tania Singer, who studied human empathy behavior when looking at someone in pain at University College London, is also skeptical: according to the researcher, philosophers are likely to regard awareness as an indispensable prerequisite for compassion. And physiologists will first want to identify altruistic motivations and behavioral expressions in order to establish empathy. Perhaps, critics Mogil build a bridge, the behavior he perceives is more a behavioral expression of knee-jerk "emotional contagion" - similar do babies who react screaming to crying babies. Real insight into the emotional world of others is not necessary.
Be that as it may: It certainly has a certain charm to discover human impulses and feelings in other fellow creatures - one can only hope that attested humanoid characteristics do not have to provide reasons for considering nature valuable. In any case, confirming empathy for mice – until sufficient evidence is found – does not have any charm, but can simply be sold better with an empathy label. By the way, another real difference between humans, mice and many other species: probably only Homo sapiens will try to expose pity in other species quite mercilessly.