Continued from Part 1 …
Animal rights are arbitrarily granted or assumed
If human rights are arbitrarily assigned, so are animal rights. The argument has been made that animals with certain properties … sentience (the definition of which moves somewhat), phylogenetic closeness to humans, or the ability to feel pain, etc. … should share some protections against painful procedures, death, or being caged because of those properties. Sorry, but no. While it could be argued that the more human a non-human animal is the more like humans they should be treated, that simplistic view in and of itself leaves out the fact that we have only by convention assigned certain expectations to the treatment of our own species. If its arbitrary for us, its arbitrary for them.
In truth, we are not going to be able to avoid some scheme for assigning animal protections, and it is likely to relate to what we do with humans somehow. I just feel that it is important to undermine the power of such arguments. They are arbitrary, post hoc, and and they should not be fetishized.
Although it is arbitrary, the anthropocentric circle is reasonable
In fact, I would argue that an anthropocentric, phylogenetic approach is reasonable because it combines many of the things that people want to see in a set of rules about treatment of non-human animals. (This does not preclude other rights-granting arguments.)
First it should be noted that the fact that humans have no very close relatives that are only barely a different species is an historically contingent fact. I think it is a very meaningful fact, so let’s be very clear about this and take a little digression with a discussion of evolutionary patterns.
Among vertebrates, it is possible to find cases where a close relative is very close phylogenetically. The southern oryx and the northern oryx in Africa, or the different kinds of gazelles, and many pairs of antelope or cervid, for instance, are all very close phylogentically. If you know all about one species, you automatically know almost all about the species that is its closest living relative. In other cases, this is not true. Pick a random persiodactyl and you may have very different results. A white rhino is not that similar to a black rhino, and the southeast Asian rhinos are different still, and the nearest relative to rhinos is nothing at all like a rhino.
So there are sets of species that are like bouquets of similar flowers … a dozen roses of differing color, all roses, also noticeably different in one attribute, but they all smell the same. And, there are sets of species that are like a display rack in a Hello Kitty store. Although one gets the feeling that there is some basic similarity (in this case overwrought cuteness) two items hanging next to each other may be designed for utterly different purposes, made of utterly different materials, and of interest to utterly different people.
Humans are in that second category. Our nearest relative is plenty like us, but also plenty different. The rhinos and their relatives (including horses, etc.) are disparate because they diversified a very long time ago, and since then have taken it in the neck competitively from other clades, mainly the artiodactyls (bovids, deer, antelopes) and have lost a lot of the branches of their evolutionary bush. The artiodactyls, on the other hand, got their shot at diversity more recently, and are in fact in the middle (or near the end) of their adaptive radiation. So, there are a lot of very similar artiodactyls because all these new species just arose. The difference between the two clades has to do with history and competitive exclusion, as well as lots of chance and circumstance, and this is typical in comparing any two vertebrate clades.
Our clade … the great apes … is also the way it is … disparate and devoid of very many close sister species … because of its history.
I think this has to do with human competitive exclusion which is a well documented phenomenon. We have killed off our nearest relatives, typically, throughout prehistory for at least the last two million years. It is a defining feature of our genus, it would seem. It has been such a consistent fact of biogeography for so long and across so much space that it would be foolish to assume that the minimum of 12 million years of evolutionary history that separates us from our nearest relatives is a random fact of phylogeny.
So it is quite possible that our “nearness” to chimpanzees, our nearest relatives, is of no consequence. It is possible, in an alternative world, that our nearest living relative is an amoeba. We would not be granting rights to the amoeba just because they are our nearest living relative.
But our nearest relatives are not amoebas: Some of the salient traits that humans posses that we tend to hold up as special are not found widely among non-human animals, but where they are found, they are found in relatively close relatives.
The Hauser Effect
An animal rights policy that specifies certain traits … the ability to count, the ability to communicate symbolically, the ability to distinguish between the Jerry Springer show and Oprah (regardless of one’s preference), etc … will quickly run aground when applied more broadly in our evolutionary tree. A special human trait might be found in chimps, but no other apes. But then, this trait could pop up in one or more primates much more distantly related.
I sometimes like to jokingly call this the Hauser Effect after my friend and colleague Marc Hauser, who has done a great deal of research with cotton tip tamarins, a kind of New World Monkey. Time and time again, a trait seen only in humans, or only in apes, or only in humans and chimps, a trait that might make a good phylogenetic marker to circumscribe a phylogenetically coherent special class of animals to which we afford a common right, is found in New World Monkeys (or some other group) by experimenters such as Hauser. These are not cases of a trait looking similar between two species by analogy. They are just as likely to be real homologies, and they are probably seen in a New World Monkey and Apes and no other primates for one or more of the following reasons:
1) Mark Hauser and others happen to work only with certain species, the experimental generation time for these species is faster than for some Old World Monkeys or apes, and Hauser and others are better funded than most, so more results emanate from their behavioral research labs;
2) There is a general tendency for certain behaviors … we can call them symbolic behavior perhaps … to arise within primates in general, and they will eventually be shown to appear more or less randomly along the several hundred primate species that exist, more often but not exclusively in apes;
3) There is something about the very small number of Old World Monkeys that have been studied in behavioral research labs (Rhesus macaques, baboons, etc.) that makes them relatively less endowed with these behaviors than the average monkey. So, by chance, we have been comparing brilliant primates (say, bonobos) with the two or three species that are simply not the sharpest knives in the phylogenetic drawer.
I’m betting on number three as a pattern overlain on number two, which is almost certainly also true. Certain species of monkey seen to be exceptionally “smart” (human-like) and “symbolic” in their behavior, and when studies on that species start, fascinating results spew into the literature. Cotton top tamarins and capuchin monkeys, both New World Monkeys, are examples of this. Among the great apes, there is probably not a lot of difference between chimps, gorillas, and orangs in overall smartosity, but there are very few behavioral lab results showing sub-linguistic, symbolic, or other human-esque behavior for orangs (most of the indicative data comes from the field). Gorillas seem to be lousy research subjects. Koko the gorilla failed the Gallup test again and again, but one day while being led back to her enclosure after once again failing the test, stopped at a randomly placed mirror in a hallway and used it to adjust the hair on her head, which amounts to passing the Gallup test that otherwise is only passed by humans and chimps. And Hauser’s cotton tops. Chimps seem like over-eager teacher-pleasing suck-ups when it comes to behavioral research. Especially bonobos.
When a human like trait is seen in another animal, it may or may not really be the same trait. It might be something that looks like the human like trait but underlying it, neurologically, is a very different process. elephants have evolved certain very human like traits with very non-human brains. The fact that they treat their dead with what looks to us like reverence, including returning to the remains, burial of the remains, and other behaviors, does not mean that their brains have crossed some phylogentic/anatomical chasm to be more like humans. Rather, it means that similar behaviors have arisen, in this case probably for similar evolutionary reasons. Intergenerational longevity of knowledge is probably critical for elephants in the wild, as is the case with humans, and perhaps in both cases reverence for the elderly and the dead emerges as an effect.
This does not make elephants more human. It does, however, make the special human trait of treatment of the dead more mundane. Perhaps reverence for the dead and the concept of post-life sentience is a more general mammalian trait than we thought, or even a widespread organism-with-brain trait, that happens to be highly developed in humans. In other words, asserting that this trait, or any other trait that is seen as “human like” and special to humans found in a distant relative is not evidence that those distant related animals should be treated like humans, but rather, that humans should not be treated so differently from those distantly related animals.
Elephants, honey bees and parrots all show human like traits with different evolutionary histories and different neurological substrates. This is not earth shattering. Behavioral scientists have understood for decades that analogy is not homology, and behavioral biologists reasonably assume that if there are phylogenetic gaps between instances of specific traits, that analogy is more likely, and if there are no or few gaps, homology is more likely. Furthermore, if the basic neurological system and sensory modalities underlying the traits is similar, homology is more likely and analogy less likely.
An example is the trait of facial contact to indicate warmth, love, closeness. Mothers touch their face to their baby’s face, lovers mush each others faces together, and so on. So, when your cat is all over your face with her face, that’s love, right? Well, it probably is in some way, but it is also said to be marking by the cat of part of its territory. If you watch the cat long enough, you will observe it “lovingly” rubbing its face on other cats, on the legs of chairs, on the ground, on a bush, on a book, or a can of soup. Cats live in an olfactory world and they have scent glands used for contact marking on their heads. It may well be that your cat is not simply marking you as territory. House cats are social. They may be using the face marking as a social signal of solidarity kinda, sorta, like how humans mush their faces together. But while face mushing “means” love and attachment in humans, it probably “signifies” (no symbolically) a state of association in cats that means “Don’t eat this one. Yet.” It only looks like the human act, which is a combination of sensory and cerebral symbolic activity.
But when chimpanzees kiss, that is likely different. Chimpanzees have human like brains, and humans and chimps share cerebral and limbic systems and syndromes that are distinct from cats and other carnivores. The list of “emotions” one would see in a cat is not the same as the list one would seen in a chimp, but human and chimp emotions are very much overlapping. Chimps seem to do “kissing” in similar contexts to humans outside of pair bonding. (Chimps don’t have pair bonding.)
The reason the chimpanzee and human kisses are probably similar is because of the similarity of the underlying neurological substrate, the similarity of sensory modalities (and thus of communicative process), the contextual similarity, and a likely evolutionary commonality. And these things are all true for one reason: Phylogentic propinquity.
Therefore, even though each and every right assigned to animals or to humans, or even to aliens, might be arbitrary, if we assign a right to humans, it seems reasonable to suggest that this right should be considered more seriously for those closely related to humans than it should be for those distantly related. So, although the underpinnings of this idea may be arbitrary, it’s implementation is not.
As a result, it can be asserted that in the absence of mitigating circumstances or other effects, the following concentric circles exist: Humans; The Great Apes, possibly ordered phylogenetically but for many reasons left as a unary group; The Old World Monkeys and New World Primates possibly ordered but, again, arguably left as a unary group; prosimians; mammals … dot-dot-dot … amoebas.