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Human/Animal Chimeras and Personhood

Imagine walking down the street and literally bumping into Bugs Bunny, or Buzz Bunny for that matter, not a fictionalized cartoon character, but a living, breathing rabbit with human attributes. Upset at you for running into him, he glares and wags a carrot in your face.

Would Elmer Fudd have the right to hunt down a real chimeric creature? Better research this. Ah, looks like Elmer Fudd is one step ahead of me at Google.

Seriously, thatâ??s not all, folks.

All you Mouseketeer fans out there --

What happens when you cross a human and a mouse? Sounds like the beginning of a bad joke but, in fact, it's a serious experiment recently carried out by a team headed by a distinguished molecular biologist, Irving Weissman, at Stanford University.

Scientists injected human brain cells into mouse foetuses, creating a strain of mice that were approximately 1% human. Weissman is considering a follow-up that would produce mice whose brains are 100% human.

What if the mice escaped the lab and began to proliferate? What might be the ecological consequences of mice who think like human beings, let loose in nature? Weissman says that he would keep a tight rein on the mice, and if they showed any signs of humanness he would kill them. Hardly reassuring. [ â??Are you a man or a mouse?â? by Jeremy Rifkin, The Guardian, March 15, 2005]

Jeremy Rifkin further states:

Fusing a human and chimpanzee embryo - which researchers say is feasible - could produce a creature so human that questions regarding its moral and legal status would throw 4,000 years of ethics into chaos. Would such a creature enjoy human rights? Would it have to pass some kind of "humanness" test to win its freedom? Would it be forced into doing menial labour or be used to perform dangerous activities?

Ethical ramifications regarding animal-human hybrids have been and continue to be examined in legal and religious forums.

Letâ??s consider the â??approximately 1% humanâ? mice that have already been created. How much â??humannessâ? would be required to qualify for â??personhoodâ? to gain legal human rights? Mice with 1% or 100% human brains? Or doesnâ??t the brain alone matter for personhood? Our concept of humanity is being challenged.

If animal-human hybrids at some point should qualify for a predetermined personhood status, they feasibly could be affected by ongoing human issues such as reproductive rights, gay marriage, and Social Security benefits, ... or even the right not to be killed while on the job (laboratory specimens). Farfetched? Maybe.

The National Academy of Sciences, America's most august scientific body, is expected to issue guidelines for chimeric research some time next month, anticipating a flurry of new experiments in the burgeoning field of human-animal chimeric experimentation.

Stay tuned.


There are at least two regards in which "100% human brain [cells]" isn't the same as "thinking like a human":

  1. There's no guarantee (and in fact, I expect the probability is very, very low) that the human brain cells will organize themselves into a human brain. What you'd have is a mouse brain made from human brain cells. It would be like retrofitting a Chrysler engine with GM parts. The result won't be a Chevy in any meaningful sense -- rather, it will be a modified (and most likely compromised) Chrysler.
  2. To paraphrase Wittgenstein: If a mouse-human chimaera spoke, would you understand it?

escoles â??

1. I agree that there is no guarantee that the human brain cells will organize themselves into a human brain.

2. If a mouse-human hybrid were able to speak, but not in understandable language to me perhaps due to its physical limitations, would that be enough indication that it was not thinking like a human?

3. In any case, escoles, whatâ??s your take on a possible human-chimpanzee hybrid?

... ethical, or plausible?

Chimeric hybrids as an ethical matter will be either a terrific problem or very little problem at all. One of the few clear benefits of contemporary capitalist culture is that it takes a liberal view of the "rights of man" -- in no small part thanks to folks like Paine, Franklyn, Jefferson and Madison, but certainly owing to their own forebears as well. It's a thread going back a ways and you're probably better suited to tease it out than I, but I would call out data points at Aquinas and in the ideas of both Stoics and Epicureans. Not to mention in ideas common to Sufism, Hasidism and the various Anabaptist derivatives.

But I digress, as usual; my point is that with major and obvious exceptions, we've drawn the "bright line" (that phrase seems really common right now...) on empathic grounds, rather than on older, more societal concepts of "personhood." And in recent decades, the fact that the world has grown so much smaller (at least in terms of Evans-Pritchard-ian "social distance") and so much more richly interdependent has given many nations moral leverage they didn't have before. So, mainstream "first worlders" -- members of "great" societies -- can essentially enforce some of their most urgent moral ideas on the emerging nations.

Naturally that can have bad consequences as well as good (e.g., our own highly impractical insistence on abstinence as a cornerstone of population- and AIDS-control efforts), but in this case, I think it's likely to have the practical effect of limiting the exploitation of sentient chimerae.

Then there's the technical aspect: Why would anyone make them? What would they be used for? By the time technology has advanced to a point where clean, viable chimerae are practical, mechanical or nano-mechanical alternatives will be more cost-effective. (A lucky, accidental way that late capitalism might once again serve a moral good.)

But there's a darker moral question with regard to the development of chimerae, and that's that it's a major crap shoot as to whether they'll be viable. Most won't work at all -- they won't get past the developmental stages, for various reasons. But as understanding of auto-immune functions improves, there will be less of that. The next frontier will be whether the chimeric implants will interfere with or conquer or be conquered by the host tissues -- i.e., will things work together? Again, that could be controlled clinically. (But that leads to the next question: If we have a chimeric being whose existence is only possible through the intervention of managing machines, then what happens if those machines break?)

But I'm getting off track again: The point I want to drive at right now is that, in order to make a functioning chimera that can be produced routinely and reliably, you'll have to have killed a shitload of them as part of your experimental process. Whether that process would be militated against by the factors I mention above, I have no idea.

escoles, thank you for your thoughtful answer, as usual. Whether plausible that viable animal-human hybrids could be created through fusing an embryo or by later chimeric implants, there are always going to be ethical and practical issues to consider.

Iâ??ll be interested to see what guidelines the National Academy of Sciences comes up with.

Nicholas Wade of The New York Times discusses chimeras in relation to the recent Guidelines for Human Embryonic Stem Cell Research.

This is a topic that fascinates me, only because it is so horrifying to me. I read through this post and it's comments (including the ones that fall after this level of reply), and hours later (now) I just had this interesting brain pop that I just had to share.

On perspective: It's interesting that we humans assume the role of superior benefactor in the inducing of our brain cells into "lesser" creatures. Could that "lesser" creature begin eventually to extend to envelope "lesser" intelligence from within our own species?

Then, still on persepctive, from another point of view... if you were the subject of experiment where a glop of chimpanzee or gorilla brain cells were induced into your brain, would you become less human? To yourself? To others?

Would the chimpanzee of gorilla recognize you as being more "them"? What would it be like to become more "them", and realize... the human species isn't so superior, after all? ;-)

Understanding DNA makeup is one thing. Inventing new recipes with it is something else entirely. Seriously, we ought not be messin' around with such things, MHO.

There is an excellent article, â??The Other Stem-Cell Debate,â? in yesterdayâ??s New York Times.

The crux of it, for me, comes near the end:

But is there a clear biological distinction between us and the rest of creation, one that should never be confounded by the scuffling of strange new feet in laboratory basements? Deacon has devoted a great deal of thought and research to such questions. While his is hardly the only view, after a career spent comparing the brains of living primates and the skulls of fossilized hominids, he says that there is little evidence for the sudden appearance of some new thing -- a uniquely human gene, a completely novel brain structure in the hominid lineage -- that sets us distinctly apart. Obviously, there has been an overall increase in brain size. But the telling difference is in more subtle shifts in proportion and connections between regions of the brain, ''a gerrymandering of the system'' that corresponds to a growing reliance on the use of language and other symbolic behavior as a means of survival. This shift, which Deacon believes began as long as two and a half million years ago, is reflected most prominently in the swollen human prefrontal cortex.

"We humans have been shaped by the use of symbols," he says. "We are embedded in a world of human creation, where demands for success and reproduction are all powerfully dependent on how well we swim through our symbolic niche."

This raises some fascinating questions, not just about the chimeras we might create with our scalpels and stem cells but also about the ones we may already have fashioned by coaxing humanlike behaviors from animals who have the latent capacity to express them. In the wild, chimpanzees and other apes do not engage in any symbolic behavior remotely comparable to what humans have evolved. But in the laboratory they can learn to communicate with sign language and other means on a par with the skills of a toddler. The difference is that the toddler's symbolic behavior becomes increasingly enriched, while the chimpanzee hits a wall. How much further could a bioengineered chimera go? Could it swim in our symbolic niche well enough to communicate what is going on inside its hybrid mind? What could it teach us about animals? What could it teach us about us? And what is the price of the knowing?

Indeed, this is the most challenging possible interpretation, in my view: what if there is nothing really that special and singular that separates us from "the animals"? What is the nature of our humanness? So many things that we identify as uniquely human (emotions like grief and amusement, language arranged into basic grammars, altruism -- I'm waiting with baited breath for evidence of the construction of narratives) have been shown to exist in other mammals and in birds.

At risk of sounding like a b-movie mad scientist: The real lapse in ethical courage may be among those who indulge their knee-jerk reaction to the "yuck factor."

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