Giving Ecstasy to Octopuses

Edsinger and Dölen have found out how to make the normally shy and retiring octopus into a party animal. They found that MDMA (phenethylamine (+/−)-3,4-methylendioxymethamphetamine, also known as Ecstasy) has prosocial effects, just as it does in humans. The indicates that the role of the serotonergic neurotransmission (that MDMA acts on) in regulating social behaviors has been evolutionarily conserved over 500 million years.

Human and octopus lineages are separated by over 500 million years of evolution and show divergent anatomical patterns of brain organization. Despite these differences, growing evidence suggests that ancient neurotransmitter systems are shared across vertebrate and invertebrate species and in many cases enable overlapping functions. Sociality is widespread across the animal kingdom, with numerous examples in both invertebrate (e.g., bees, ants, termites, and shrimps) and vertebrate (e.g., fishes, birds, rodents, and primates) lineages [6]. Serotonin is an evolutionarily ancient molecule that has been implicated in regulating both invertebrate and vertebrate social behaviors, raising the possibility that this neurotransmitter’s prosocial functions may be conserved across evolution. Members of the order Octopoda are predominantly asocial and solitary. Although at this time it is unknown whether serotonergic signaling systems are functionally conserved in octopuses, ethological studies indicate that agonistic behaviors are suspended during mating, suggesting that neural mechanisms subserving social behaviors exist in octopuses but are suppressed outside the reproductive period. Here we provide evidence that, as in humans, the phenethylamine (+/−)-3,4-methylendioxymethamphetamine (MDMA) enhances acute prosocial behaviors in Octopus bimaculoides. This finding is paralleled by the evolutionary conservation of the serotonin transporter (SERT, encoded by the Slc6A4 gene) binding site of MDMA in the O. bimaculoides genome. Taken together, these data provide evidence that the neural mechanisms subserving social behaviors exist in O. bimaculoides and indicate that the role of serotonergic neurotransmission in regulating social behaviors is evolutionarily conserved.

Deep origins of consciousness

I want to recommend an engaging book by Peter Godfrey-Smith that I have read recently, "Other Minds: The Octopus, theSea, and the Deep Origins of Consciousness." Below are a few clips pointing to some of his core points:

Sentience is brought into being somehow from the evolution of sensing and acting; it involves being a living system with a point of view on the world around it. If we take that approach, though, a perplexity we run into immediately is the fact that those capacities are so widespread— they are found far outside the organisms that are usually thought to have experience of some kind. Even bacteria sense the world and act... A case can be made that responses to stimuli, and the controlled flow of chemicals across boundaries, are an elementary part of life itself. Unless we conclude that all living things have a modicum of subjective experience— a view I don’t regard as insane, but surely one that would need a lot of defense— there must be something about the way animals deal with the world that makes a crucial difference.

The senses can do their basic work, and actions can be produced, with all this happening “in silence” as far as the organism’s experience is concerned. Then, at some stage in evolution, extra capacities appear that do give rise to subjective experience: the sensory streams are brought together, an “internal model” of the world arises, and there’s a recognition of time and self.

What we’ve learned over the last thirty years or so is that there’s a particular style of processing— one that we use to deal especially with time, sequences, and novelty— that brings with it conscious awareness, while a lot of other quite complex activities do not.

Baars suggested that we are conscious of the information that has been brought into a centralized “workspace” in the brain. Dehaene adopted and developed this view. A related family of theories claim that we are conscious of whatever information is being fed into working memory,These views don’t hold that the lights went on in a sudden flash, but they do hold that the “waking up” came late in the history of life and was due to features that are clearly seen only in animals like us.

...certainly there’s an alternative to consider. I’ll call this the transformation view. It holds that a form of subjective experience preceded late-arising things like working memory, workspaces, the integration of the senses, and so on. These complexities, when they came along, transformed what it feels like to be an animal. Experience has been reshaped by these features, but it was not brought into being by them. The best argument I can offer for this alternative view is based on the role in our lives of what seem like old forms of subjective experience that appear as intrusions into more organized and complex mental processes. Consider the intrusion of sudden pain, or of what the physiologist Derek Denton calls the primordial emotions— feelings which register important bodily states and deficiencies, such as thirst or the feeling of not having enough air. As Denton says, these feelings have an “imperious” role when they are present: they press themselves into experience and can’t easily be ignored. Do you think that those things (pain, shortness of breath, etc.) only feel like something because of sophisticated cognitive processing in mammals that has arisen late in evolution? I doubt it. Instead, it seems plausible that an animal might feel pain or thirst without having an “inner model” of the world, or sophisticated forms of memory.

Subjective experience does not arise from the mere running of the system, but from the modulation of its state, from registering things that matter. These need not be external events; they might arise internally. But they are tracked because they matter and require a response. Sentience has some point to it. It’s not just a bathing in living activity.

By the Cambrian, the vertebrates were already on their own path (or their own collection of paths), while arthropods and mollusks were on others. Suppose it’s right that crabs, octopuses, and cats all have subjective experience of some kind. Then there were at least three separate origins for this trait, and perhaps many more than three. Later, as the machinery described by Dehaene, Baars, Milner, and Goodale comes on line, an integrated perspective on the world arises and a more definite sense of self. We then reach something closer to consciousness. I don’t see that as a single definite step. Instead, I see “consciousness” as a mixed-up and overused but useful term for forms of subjective experience that are unified and coherent in various ways. Here, too, it is likely that experience of this kind arose several times on different evolutionary paths: from white noise, through old and simple forms of experience, to consciousness.

The misunderstood sixth mass extinction

Paul Ehrlich, 50 years after the publication of "The Population Bomb," together with Gerardo Ceballos, has written a concise rebuttal of scientists (and the politicians who listen to them) who suggest that the current anthropogenic mass extinction will not have dire consequences:

Scientific misunderstanding about the nature and consequences of the sixth mass extinction has led to confusion among policy-makers and the public. Scientists agree that there have been five mass extinctions in the past 600 million years (1). Although scientists also agree that Earth is now suffering the sixth mass extinction, they disagree about its consequences. Mass extinctions are defined as the loss of the majority of species in a relatively short geological time, caused by a catastrophic natural event (2). Some scientists argue that there is no reason for concern about the sixth mass extinction because extinction is normal, simply an inevitable consequence of the process of evolution (3, 4). This misunderstanding ignores some critical issues. First, the rate of species extinction is now as much as 100 times that of the “normal rate” throughout geological time (5, 6). Second, like the past mass extinctions, the current episode is not an inevitable consequence of the process of evolution. Rather, it is the result of a rare event changing the environment so quickly that many organisms cannot evolve in response to it.

In theory, evolution on Earth could proceed as long as conditions permitted with no mass extinction events. That has been the case for vast stretches of geological time between occasional encounters with unusual environmental circumstances. Extinctions did occur, but not suddenly and nearly universally, as is happening now (7, 8). The rate and extent of current extinctions is similar to those of past mass extinctions, not the intervals between them (9, 10). If past mass extinctions are any guide to the rate at which usual evolutionary diversification processes could restore a reasonable level of biodiversity and ecosystem services, the wait is likely to be millions, or even tens of millions of years (8, 9).

At the time of the past mass extinctions, there was no industrialized human population of almost 8 billion people utterly dependent on the ecosystem services biodiversity helps provide, such as pollination, pest control, and climate amelioration (7, 8, 11). Scientists who deny that the current mass extinction has dire consequences, and policy-makers who listen to them, fail to appreciate the penalties human civilization will suffer for continuing on society's business-as-usual course (2–5). Moreover, beyond the consequences to humans, exterminating most of the only known living things with which we share the universe is clearly wrong (5–8, 12). The future of life on Earth, and human well-being, depends on the actions that we take to reduce the extinction of populations and species in the next two decades (8). It is irresponsible and unethical not to act despite the overwhelming scientific evidence indicating the severity of the current mass extinction event.

References (see Google Scholar for all)

1. W. J. Ripple et al., Bioscience 67, 197 (2017). 2. A. Hallam, P. B. Wignall, Mass Extinctions and Their Aftermath (Oxford University Press, UK. 1997). 3. S. Brand, “Rethinking extinction” (2015); https://aeon.co/essays/we-are-not-edging-up-to-a-mass-extinction. 4. C. D. Thomas, Inheritors of the Earth (Hachette, UK, 2017). 5. S. L. Pimm et al., Science, 344, 1246752 (2014). 6. G. Ceballos et al., Sci. Adv. 1, e1400253 (2015). 7. R. Dirzo et al., Science 345, 401 (2014). 8. G. Ceballos et al., The Annihilation of Nature: Human Extinction of Birds and Mammals (JHU Press, 2015). 9. D. Jablonski, Evol. Biol. 44, 451 (2017). 10.A. D. Barnosky et al., Nature 471, 51 (2011). 11.C. A. Hallmann, PLOS One 12, e0185809 (2017).C 12.P. R. Ehrlich, A. H. Ehrlich, Proc. R. Soc. B 280, 20122845 (2013).

Evolutionary cognition - bees demonstrate an understanding of zero

Howard et al. demonstrate an astounding evolutionary convergence by showing that insects have developed the concept of zero, a capability once thought to be a unique major intellectual advance in humans. The last common ancestor of humans and the honeybees used in the experiments lived more than 600 million years ago. Their abstract:

Some vertebrates demonstrate complex numerosity concepts—including addition, sequential ordering of numbers, or even the concept of zero—but whether an insect can develop an understanding for such concepts remains unknown. We trained individual honey bees to the numerical concepts of “greater than” or “less than” using stimuli containing one to six elemental features. Bees could subsequently extrapolate the concept of less than to order zero numerosity at the lower end of the numerical continuum. Bees demonstrated an understanding that parallels animals such as the African grey parrot, nonhuman primates, and even preschool children.

...and a description of their experiment from a review by Nieder:

...the authors lured free-flying honey bees from maintained hives to their testing apparatus (see the figure) and marked the insects with color for identification. They rewarded the bees for discriminating displays on a screen that showed different numbers (numerosities) of items. The researchers controlled for systematic changes in the appearance of the numerosity displays that occur when the number of items is changed. They thus ensured that the bees were discriminating between different numbers, rather than responding to low-level visual cues.

First, the researchers trained the bees to rank two numerosity displays at a time. Over the course of training, they changed the numbers presented to encourage rule learning. Bees from one group were rewarded with a sugar solution whenever they flew to the display showing more items, thereby following a greater-than rule. The other group of bees was trained on the less-than rule and rewarded for landing at the display that presented fewer items. The bees learned to master this task with displays consisting of one to four items; they were able to do so not only for familiar numerosity displays but also for new displays.

Next, the researchers occasionally inserted displays containing no item. Would the bees understand that empty displays could be ranked with countable numerosities? Indeed, the bees obeying the less-than rule spontaneously landed on displays showing no item, that is, an empty set (see the figure). In doing so, bees understood that the empty set was numerically smaller than sets of one, two, or more items. Further experiments confirmed that this behavior was related to quantity estimation and not a product of the learning history.

Ancient origins of walking on land - the walking skate.

From Jung et al., in the Feb. 8 issue of Cell, report finding that the circuits underlying vertebrate ambulation on dry land appear in a skate many millions of years before fish crawled out of the prehistoric ocean.




Highlights

•The little skate Leucoraja erinacea exhibits bipedal walking-like behaviors 

•Neuronal subtypes essential for walking originated in primitive jawed fish 

•Fin and limb motor neurons share a common Hox-dependent gene network 

•Modulation of Hox patterning facilitates evolutionary changes in MN organization

Summary

Walking is the predominant locomotor behavior expressed by land-dwelling vertebrates, but it is unknown when the neural circuits that are essential for limb control first appeared. Certain fish species display walking-like behaviors, raising the possibility that the underlying circuitry originated in primitive marine vertebrates. We show that the neural substrates of bipedalism are present in the little skate Leucoraja erinacea, whose common ancestor with tetrapods existed ∼420 million years ago. Leucoraja exhibits core features of tetrapod locomotor gaits, including left-right alternation and reciprocal extension-flexion of the pelvic fins. Leucoraja also deploys a remarkably conserved Hox transcription factor-dependent program that is essential for selective innervation of fin/limb muscle. This network encodes peripheral connectivity modules that are distinct from those used in axial muscle-based swimming and has apparently been diminished in most modern fish. These findings indicate that the circuits that are essential for walking evolved through adaptation of a genetic regulatory network shared by all vertebrates with paired appendages.

How is American (and World) governance evolving?

So... what is the United State to become? From the recent outpouring of Op-Ed pieces you can take your choice: Autocracy, Plutocracy, Oligarchy, Kleptocracy... with liberal democracy viewed as vitally threatened. Articles by Thomas Edsall and Andrew Sullivan describe how American democracy is destroying itself, as Roger Cohen sadly notes the irreversible passing of the Pax Americana, an ordering of the world that began with Woodrow Wilson's 14 points speech one hundred years ago. David Frum outlines steps towards Autocracy as Jonathan Rauch discusses whether Trump will be able to govern as an authoritarian. Paul Krugman notes how the current tax reform will enormously enhance the ongoing process of entrenching a hereditary plutocracy that actually runs the country.  Articles by Fareed Zakaria and Thomas Edsall describe how the liberal establishment has failed to understand its own role in the rise of contemporary conservatism, how its social and economic policies have disadvantaged formerly middle class voters more motivated by issues surrounding religion, race, and culture than they are by economics, thus fueling a rise of nationalism, nativism and xenophobia in both the U.S. and Europe.  Regarding this last point, I want to paste in here the final paragraphs of an Edsall Op-Ed piece noting Eric Schnurer's argument that blue America has over the last decade declared war on the "red way of life."

The political, economic, and cultural triumph nationwide of a set of principles and realities essentially alien to large numbers of Americans is viewed as (a) being imposed upon them, and (b) overturning much of what they take for granted in their lives — and I don’t think they’re wrong about that. I think they’ve risen in angry revolt, and now intend to give back to the “elite” in the same terms that they’ve been given to. I don’t think this is good — in fact, I think it’s a very dangerous situation — but I think we need to understand it in order to responsibly address it.

Do liberals in fact need to understand — or empathize with — their many antagonists, the men and women who are sharply critical of the liberal project?

Steven Pinker, a professor of psychology at Harvard, observes that “believers in liberal democracy have unilaterally disarmed in the defense of the institution” by agreeing in many cases with the premise of the Trump campaign: “that the country is a hopeless swamp.” This left Democrats “defenseless when he proposed to drain it.” Where, Pinker asks,

are the liberals who are willing to say that liberal democracy has worked? That environmental regulations have slashed air pollutants while allowing Americans to drive more miles and burn more fuel? That social transfers have reduced poverty rates fivefold? That globalization has allowed Americans to afford more food, clothing, TVs, cars, and air-conditioners? That international organizations have prevented nuclear war, and reduced the rate of death in warfare by 90 percent? That environmental treaties are healing the hole in the ozone layer?

Pinker remains confident:

Progress always must fight headwinds. Human nature doesn’t change, and the appeal of regressive impulses is perennial. The forces of liberalism, modernity, cosmopolitanism, the open society, and Enlightenment values always have to push against our innate tribalism, authoritarianism, and thirst for vengeance. We can even recognize these instincts in ourselves, even in Trump’s cavalier remarks about the rule of law...Over the longer run, I think the forces of modernity prevail — affluence, education, mobility, communication, and generational replacement. Trumpism, like Brexit and European populism, are old men’s movements: support drops off sharply with age.

Pinker is optimistic about the future. I hope he is right.

The problem is that even if Pinker is right, his analysis does not preclude a sustained period in which the anti-democratic right dominates American politics. There is no telling how long it will be before the movement Trump has mobilized will have run its course. Nor can we anticipate — if and when Trumpism does implode — how extensive the damage will be that Pinker’s “forces of modernity” will have to repair.

But... what if all of this wringing of hands about changes the political order is a thin veneer over deeper changes that are really going to end up controlling the show?  One is seeing now the rise of a de facto world government of interlocked and interdependent giant corporations, mainly in the U.S. and China (think Apple and Foxconn) versed in the neuroeconomic techniques central to influencing the behaviors, desires, and consumptions of their subjects.  They are assembling a level of power that might increasingly override the ability of individual nation states to contest or control their actions.  Will this ensemble nudge towards mirroring the values of liberalism currently reflected in the public stances of the largest U.S. corporations, or will the political accommodations shown by  their Asian counterparts be more likely to prevail?

From learning to instinct

I pass on a few chunks from the Science Perspective article by Robinson and Barron:

An animal mind is not born as an empty canvas: Bottlenose dolphins know how to swim and honey bees know how to dance without ever having learned these skills. Little is known about how animals acquire the instincts that enable such innate behavior. Instincts are widely held to be ancestral to learned behavior. Some have been elegantly analyzed at the cellular and molecular levels, but general principles do not exist. Based on recent research, we argue instead that instincts evolve from learning and are therefore served by the same general principles that explain learning.

Tierney first proposed in 1986 that instincts can evolve from behavioral plasticity, but the hypothesis was not widely accepted, perhaps because there was no known mechanism. Now there is a mechanism, namely epigenetics. DNA methylation, histone modifications, and noncoding RNAs all exert profound effects on gene expression without changing DNA sequence. These mechanisms are critical for orchestrating nervous system development and enabling learning-related neural plasticity.

For example, when a mouse has experienced fear of something, changes in DNA methylation and chromatin structure in neurons of the hippocampus help stabilize long-term changes in neural circuits. These changes help the mouse to remember what has been learned and support the establishment of new behavioral responses. Epigenetic mechanisms that support instinct by operating on developmental time scales also support learning by operating on physiological time scales. Evolutionary changes in epigenetic mechanisms may sculpt a learned behavior into an instinct by decreasing its dependence on external stimuli in favor of an internally regulated program of neural development (see the figure).

There is evidence for such epigenetically driven evolutionary changes in behavior. For example, differences in innate aggression levels between races of honey bees can be attributed to evolutionary changes in brain gene expression that also control the onset of aggressive behavior when threatened. These kinds of changes can also explain more contemporary developments, including new innate aspects of mating and foraging behavior in house finches associated with their North American invasion 75 years ago, and new innate changes in the frequency and structure of song communication in populations of several bird species now living in urban environments. We propose that these new instincts have emerged through evolutionary genetic changes that acted on initially plastic behavioral responses.

Termite castles, human minds, and Daniel Dennett.

After reading through Rothman’s New Yorker article on Daniel Dennett, I downloaded Dennett’s latest book, “From Bacteria to Bach and Back” to check out his bottom lines, which should be familiar to readers of MindBlog. (In the 1990’s, when I was teaching my Biology of Mind course at the Univ. of Wisconsin, I invited Dennett to give a lecture there.)  

I was surprised to find limited or no references to the work of major figures such Thomas Metzinger, Michael Graziano, Antonio Damasio, and others. The ideas in Chapter 14, “Consciousness as an Evolved User-Illusion” have been lucidly outlined earlier in Metzinger’s book “The Ego Tunnel,” and in Graziano’s “Consciousness and the Social Brain.”   (Academics striving to be the most prominent in their field are not known for noting the efforts of their competitors.)

The strongest sections in the book are his explanations of the work and ideas of others. I want to pass on a few chunks. The first is from Chapter 14:

,,,according to the arguments advanced by the ethologist and roboticist David McFarland (1989), “Communication is the only behavior that requires an organism to self-monitor its own control system.” Organisms can very effectively control themselves by a collection of competing but “myopic” task controllers, each activated by a condition (hunger or some other need, sensed opportunity, built-in priority ranking, and so on). When a controller’s condition outweighs the conditions of the currently active task controller, it interrupts it and takes charge temporarily. (The “pandemonium model” by Oliver Selfridge [1959] is the ancestor of many later models.) Goals are represented only tacitly, in the feedback loops that guide each task controller, but without any global or higher level representation. Evolution will tend to optimize the interrupt dynamics of these modules, and nobody’s the wiser. That is, there doesn’t have to be anybody home to be wiser! Communication, McFarland claims, is the behavioral innovation which changes all that. Communication requires a central clearing house of sorts in order to buffer the organism from revealing too much about its current state to competitive organisms. As Dawkins and Krebs (1978) showed, in order to understand the evolution of communication we need to see it as grounded in manipulation rather than as purely cooperative behavior. An organism that has no poker face, that “communicates state” directly to all hearers, is a sitting duck, and will soon be extinct (von Neumann and Morgenstern 1944). What must evolve to prevent this exposure is a private, proprietary communication-control buffer that creates opportunities for guided deception— and, coincidentally, opportunities for self-deception (Trivers 1985)— by creating, for the first time in the evolution of nervous systems, explicit and more globally accessible representations of its current state, representations that are detachable from the tasks they represent, so that deceptive behaviors can be formulated and controlled without interfering with the control of other behaviors.

It is important to realize that by communication, McFarland does not mean specifically linguistic communication (which is ours alone), but strategic communication, which opens up the crucial space between one’s actual goals and intentions and the goals and intentions one attempts to communicate to an audience. There is no doubt that many species are genetically equipped with relatively simple communication behaviors (Hauser 1996), such as stotting, alarm calls, and territorial marking and defense. Stereotypical deception, such as bluffing in an aggressive encounter, is common, but a more productive and versatile talent for deception requires McFarland’s private workspace. For a century and more philosophers have stressed the “privacy” of our inner thoughts, but seldom have they bothered to ask why this is such a good design feature. (An occupational blindness of many philosophers: taking the manifest image as simply given and never asking what it might have been given to us for.)

The second chunk I pass on is from the very end of the book, describing Seabright’s ideas:

Seabright compares our civilization with a termite castle. Both are artifacts, marvels of ingenious design piled on ingenious design, towering over the supporting terrain, the work of vastly many individuals acting in concert. Both are thus by-products of the evolutionary processes that created and shaped those individuals, and in both cases, the design innovations that account for the remarkable resilience and efficiency observable were not the brain-children of individuals, but happy outcomes of the largely unwitting, myopic endeavors of those individuals, over many generations. But there are profound differences as well. Human cooperation is a delicate and remarkable phenomenon, quite unlike the almost mindless cooperation of termites, and indeed quite unprecedented in the natural world, a unique feature with a unique ancestry in evolution. It depends, as we have seen, on our ability to engage each other within the “space of reasons,” as Wilfrid Sellars put it. Cooperation depends, Seabright argues, on trust, a sort of almost invisible social glue that makes possible both great and terrible projects, and this trust is not, in fact, a “natural instinct” hard-wired by evolution into our brains. It is much too recent for that. Trust is a by-product of social conditions that are at once its enabling condition and its most important product. We have bootstrapped ourselves into the heady altitudes of modern civilization, and our natural emotions and other instinctual responses do not always serve our new circumstances. Civilization is a work in progress, and we abandon our attempt to understand it at our peril. Think of the termite castle. We human observers can appreciate its excellence and its complexity in ways that are quite beyond the nervous systems of its inhabitants. We can also aspire to achieving a similarly Olympian perspective on our own artifactual world, a feat only human beings could imagine. If we don’t succeed, we risk dismantling our precious creations in spite of our best intentions. Evolution in two realms, genetic and cultural, has created in us the capacity to know ourselves. But in spite of several millennia of ever-expanding intelligent design, we still are just staying afloat in a flood of puzzles and problems, many of them created by our own efforts of comprehension, and there are dangers that could cut short our quest before we— or our descendants— can satisfy our ravenous curiosity.

And, from Dennett’s wrap-up summary of the book:

Returning to the puzzle about how brains made of billions of neurons without any top-down control system could ever develop into human-style minds, we explored the prospect of decentralized, distributed control by neurons equipped to fend for themselves, including as one possibility feral neurons, released from their previous role as docile, domesticated servants under the selection pressure created by a new environmental feature: cultural invaders. Words striving to reproduce, and other memes, would provoke adaptations, such as revisions in brain structure in coevolutionary response. Once cultural transmission was secured as the chief behavioral innovation of our species, it not only triggered important changes in neural architecture but also added novelty to the environment— in the form of thousands of Gibsonian affordances— that enriched the ontologies of human beings and provided in turn further selection pressure in favor of adaptations— thinking tools— for keeping track of all these new opportunities. Cultural evolution itself evolved away from undirected or “random” searches toward more effective design processes, foresighted and purposeful and dependent on the comprehension of agents: intelligent designers. For human comprehension, a huge array of thinking tools is required. Cultural evolution de-Darwinized itself with its own fruits. 

This vantage point lets us see the manifest image, in Wilfrid Sellars’s useful terminology, as a special kind of artifact, partly genetically designed and partly culturally designed, a particularly effective user-illusion for helping time-pressured organisms move adroitly through life, availing themselves of (over) simplifications that create an image of the world we live in that is somewhat in tension with the scientific image to which we must revert in order to explain the emergence of the manifest image. Here we encounter yet another revolutionary inversion of reasoning, in David Hume’s account of our knowledge of causation. We can then see human consciousness as a user-illusion, not rendered in the Cartesian Theater (which does not exist) but constituted by the representational activities of the brain coupled with the appropriate reactions to those activities (“ and then what happens?”). 

This closes the gap, the Cartesian wound, but only a sketch of this all-important unification is clear at this time. The sketch has enough detail, however, to reveal that human minds, however intelligent and comprehending, are not the most powerful imaginable cognitive systems, and our intelligent designers have now made dramatic progress in creating machine learning systems that use bottom-up processes to demonstrate once again the truth of Orgel’s Second Rule: Evolution is cleverer than you are. Once we appreciate the universality of the Darwinian perspective, we realize that our current state, both individually and as societies, is both imperfect and impermanent. We may well someday return the planet to our bacterial cousins and their modest, bottom-up styles of design improvement. Or we may continue to thrive, in an environment we have created with the help of artifacts that do most of the heavy cognitive lifting their own way, in an age of post-intelligent design. There is not just coevolution between memes and genes; there is codependence between our minds’ top-down reasoning abilities and the bottom-up uncomprehending talents of our animal brains. And if our future follows the trajectory of our past— something that is partly in our control— our artificial intelligences will continue to be dependent on us even as we become more warily dependent on them.

The above excerpts are from: Dennett, Daniel C. (2017-02-07). From Bacteria to Bach and Back: The Evolution of Minds (Kindle Locations 6819-6840). W. W. Norton & Company. Kindle Edition.

Can evolution have a 'higher purpose'?

I want to point to this essay by Robert Wright, author of "The Moral Animal," who makes the point that arguments that life on earth may have some larger purpose do not necessarily have to depart from a scientific worldview, invoke supernatural beings, or depart from the model of evolution by natural selection. Among these arguments are:

... “simulation” scenarios, which hold that our seemingly tangible world is actually a kind of projection emanating from some sort of mind-blowingly powerful computer; and the history of our universe, including evolution on this planet, is the unfolding of a computer algorithm...When an argument for higher purpose is put this way — that is, when it doesn’t involve the phrase “higher purpose” and, further, is cast more as a technological scenario than a metaphysical one — it is considered intellectually respectable. I don’t mean there aren’t plenty of people who dismiss it. I’m talking about how people dismiss it. [Neil deGrasse Tyson and Elon Musk find this view plausible.]

Wright quotes from a conversation with William Hamilton, who says:

There’s one theory of the universe that I rather like — I accept it in an almost joking spirit — and that is that Planet Earth in our solar system is a kind of zoo for extraterrestrial beings who dwell out there somewhere. And this is the best, the most interesting experiment they could set up: to set up the evolution on Planet Earth going in such a way that it would produce these really interesting characters — humans who go around doing things — and they watch their experiment, interfering hardly at all so that almost everything we do comes out according to the laws of nature. But every now and then they see something which doesn’t look quite right — this zoo is going to kill itself off if they let you do this or that.” So, he continued, these extraterrestrials “insert a finger and just change some little thing. And maybe those are the miracles which the religious people like to so emphasize.” He reiterated: “I put it forward in an almost joking spirit. But I think it

Another scenario:

...emerges from one version of physicist Lee Smolin’s theory of “cosmological natural selection.” Smolin thinks our universe may itself be a product of a kind of evolution: maybe universes can replicate themselves via black holes, so over time — over a lot of time — you get universes whose physical laws are more and more conducive to replication. (So that’s why our universe is so good at black-hole making!) In some variants of Smolin’s theory — such as those developed by the late cosmologist Edward Harrison and the mathematician Louis Crane — intelligent beings can play a role in this replication once their technology reaches a point where they can produce black holes. So through cosmological natural selection you’d get universes whose physical properties were more and more conducive to the evolution of intelligent life. This might explain the much-discussed observation that the physical constants of this universe seem “fine-tuned” to permit the emergence of life.

Wilson's ending points:

I think discussion of higher purpose should be respectable even in a scientific age. I don’t mean I buy the simulation scenario in particular, or the space alien scenario, or the cosmological natural selection scenario. But I do think there’s reason to suspect that there’s some point to this exercise we Earthlings are engaged in, some purpose imbued by something — and that, even if identifying that something is for now hopeless, there are grounds for speculating about what the point of the exercise is.

I won’t elaborate much on this, since I’ve done that elsewhere, arguing that higher purpose can be framed as a hypothesis, and that evidence for or against the hypothesis can be marshaled. But I will say that the evidence I see for purpose includes not just the direction of biological evolution, but the direction of technological evolution and of the broader social and cultural evolution it drives — the evolution that has carried us from hunter-gatherer bands to the brink of a cohesive global community. And if the purpose involves sustaining this direction — becoming a true global community — then it would seem to include moral progress. In particular, our purpose would involve transcending the psychology of tribalism that can otherwise divide people along ethnic, national, religious and ideological lines. Which would mean — in light of recent political and social developments in the United States and abroad — that our work is cut out for us.

Climate disasters act as threat multipliers in ethnic conflicts.

Schleussner et al. offer a proof of a common assumption about the effects of climate disasters: that they drive people further apart rather than closer together:

Social and political tensions keep on fueling armed conflicts around the world. Although each conflict is the result of an individual context-specific mixture of interconnected factors, ethnicity appears to play a prominent and almost ubiquitous role in many of them. This overall state of affairs is likely to be exacerbated by anthropogenic climate change and in particular climate-related natural disasters. Ethnic divides might serve as predetermined conflict lines in case of rapidly emerging societal tensions arising from disruptive events like natural disasters. Here, we hypothesize that climate-related disaster occurrence enhances armed-conflict outbreak risk in ethnically fractionalized countries. Using event coincidence analysis, we test this hypothesis based on data on armed-conflict outbreaks and climate-related natural disasters for the period 1980–2010. Globally, we find a coincidence rate of 9% regarding armed-conflict outbreak and disaster occurrence such as heat waves or droughts. Our analysis also reveals that, during the period in question, about 23% of conflict outbreaks in ethnically highly fractionalized countries robustly coincide with climatic calamities. Although we do not report evidence that climate-related disasters act as direct triggers of armed conflicts, the disruptive nature of these events seems to play out in ethnically fractionalized societies in a particularly tragic way. This observation has important implications for future security policies as several of the world’s most conflict-prone regions, including North and Central Africa as well as Central Asia, are both exceptionally vulnerable to anthropogenic climate change and characterized by deep ethnic divides.

Yes, there have been aliens.

This post falls under the "random curious stuff" category in MindBlog's description line. Adam Frank gives an interesting account of work he has published with Woodruff Sullivan arguing that we now have enough information to conclude that alien civilizations have almost certainly existed at some point in cosmic history.

Among scientists, the probability of the existence of an alien society with which we might make contact is discussed in terms of something called the Drake equation.... Drake identified seven factors on which that number would depend, and incorporated them into an equation.

The first factor was the number of stars born each year. The second was the fraction of stars that had planets. After that came the number of planets per star that traveled in orbits in the right locations for life to form (assuming life requires liquid water). The next factor was the fraction of such planets where life actually got started. Then came factors for the fraction of life-bearing planets on which intelligence and advanced civilizations (meaning radio signal-emitting) evolved. The final factor was the average lifetime of a technological civilization.

In 1961, only the first factor — the number of stars born each year — was understood. And that level of ignorance remained until very recently...Three of the seven terms in Drake’s equation are now known. We know the number of stars born each year. We know that the percentage of stars hosting planets is about 100. And we also know that about 20 to 25 percent of those planets are in the right place for life to form. This puts us in a position, for the first time, to say something definitive about extraterrestrial civilizations — if we ask the right question.

In our recent paper, Professor Sullivan and I did this by shifting the focus of Drake’s equation. Instead of asking how many civilizations currently exist, we asked what the probability is that ours is the only technological civilization that has ever appeared. By asking this question, we could bypass the factor about the average lifetime of a civilization. This left us with only three unknown factors, which we combined into one “biotechnical” probability: the likelihood of the creation of life, intelligent life and technological capacity.

You might assume this probability is low, and thus the chances remain small that another technological civilization arose. But what our calculation revealed is that even if this probability is assumed to be extremely low, the odds that we are not the first technological civilization are actually high. Specifically, unless the probability for evolving a civilization on a habitable-zone planet is less than one in 10 billion trillion, then we are not the first.

To give some context for that figure: In previous discussions of the Drake equation, a probability for civilizations to form of one in 10 billion per planet was considered highly pessimistic. According to our finding, even if you grant that level of pessimism, a trillion civilizations still would have appeared over the course of cosmic history.

In other words, given what we now know about the number and orbital positions of the galaxy’s planets, the degree of pessimism required to doubt the existence, at some point in time, of an advanced extraterrestrial civilization borders on the irrational.

Nature's warning system.

A colleague in my Chaos and Complexity discussion group at the Univ. of Wisconsin passed on this Atlantic article in which my Zoology colleague Steve Carpenter is extensively quoted, which is well worth reading. Complex systems, like ecological food webs, the brain, and the climate, give off characteristic signals when a disastrous transformation is around the corner.

The evolution of music from emotional signals

I want to pass on the slightly edited abstract of a recent article on the evolutionary origins of music, "Music evolution and neuroscience," in Progress in Brain Research, written by my Univ. of Wisconsin colleague Charles Snowdon.

There have been many attempts to discuss the evolutionary origins of music. We review theories of music origins and take the perspective that music is originally derived from emotional signals in both humans and animals. An evolutionary approach has two components: First, is music adaptive? How does it improve reproductive success? Second, what, if any, are the phylogenetic origins of music? Can we find evidence of music in other species? We show that music has adaptive value through emotional contagion, social cohesion, and improved well-being. We trace the roots of music through the emotional signals of other species suggesting that the emotional aspects of music have a long evolutionary history. We show how music and speech are closely interlinked with the musical aspects of speech conveying emotional information. We describe acoustic structures that communicate emotion in music and present evidence that these emotional features are widespread among humans and also function to induce emotions in animals. Similar acoustic structures are present in the emotional signals of nonhuman animals. We conclude with a discussion of music designed specifically to induce emotional states in animals, both cotton top tamarin monkeys and domestic cats.

More evolution cartoons

I pass this on from a recent seminar presentation to the Chaos group at the Univ. of Wisconsin... There must be hundreds of cartoons that take a different tack on this sequence:

Convergent evolution of numerosity detection in bird and primate brains.

From Ditz and Nieder:

Birds are known for their advanced numerical competence, although a six-layered neocortex that is thought to enable primates with the highest levels of cognition is lacking in birds. We recorded neuronal activity from an endbrain association area termed nidopallium caudolaterale (NCL) in crows that discriminated the number of items in displays. NCL neurons were tuned to preferred numerosities. Neuronal discharges were relevant for the crows’ correct performance. Both the neuronal and the behavioral tuning functions were best described on a logarithmic number line, just as predicted by the psychophysical Weber–Fecher Law. The behavioral and neuronal numerosity representations in the crow reflect surprisingly well those found in the primate association cortex. This finding suggests that distantly related vertebrates with independently developed endbrains adopted similar neuronal solutions to process quantity - convergent evolution of a superior solution to a common computational problem.

Economic origins of ultrasociality

Gowdy and Krall, in a manuscript under review by Behavioral and Brain Sciences, argue that the transition to agriculture in ants, termites, and our humans species generated the need for the extreme role specializations and ultrasociality that distinguish us from social species that depend on foraging for food. (Interested readers can obtain a copy of the MS from me).  I pass on a clip from the introduction, followed by their abstract.

With the widespread adoption of agriculture some 10,000 years ago human societies took on some important characteristics shared with social insects—ants and termites in particular—that also engage in the production of their own food. These characteristics represented a sharp break in the evolutionary history of these lineages and led to two important outcomes (1) ecosystem domination as a product of a dramatic increase in population size and much more intensive resource exploitation and (2) the suppression of individual autonomy as the group itself became the focus of economic organization. The evolution of agriculture in fungus-growing ants and termites, and in human societies, is an example of convergent evolution—the independent evolution of similar characteristics in species not closely related. In terms of genetics, ants, humans and termites could hardly be more different. Yet in all three lineages similar patterns of economic organization emerge through similar selection pressures. We use the term ultrasociality to refer to these lineages and we address the question of its origin through the fundamental question of evolutionary biology: “where did something come from and what were the selection pressures that favored its spread?”

Abstract:

Ultrasociality refers to the social organization of a few species, including humans and some social insects, having complex division of labor, city states and an almost exclusive dependence on agriculture for subsistence. We argue that the driving forces in the evolution of these ultrasocial societies were economic. With the agricultural transition, species could directly produce their own food and this was such a competitive advantage that those species now dominate the planet. Once underway, this transition was propelled by the selection of withinspecies groups that could best capture the advantages of (1) actively managing the inputs to food production, (2) a more complex division of labor, and (3) increasing returns to larger scale and larger group size. Together these factors reoriented productive life and radically altered the structure of these societies. Once agriculture began, populations expanded as these economic drivers opened up new opportunities for the exploitation of resources and the active management of inputs to food production. With intensified group-level competition, larger populations and intensive resource exploitation became competitive advantages and the “social conquest of earth” was underway. Ultrasocial species came to dominate the earth’s ecosystems. Ultrasociality also brought a loss of autonomy for individuals within the group. We argue that exploring the common causes and consequences of ultrasociality in humans and the social insects that adopted agriculture can provide fruitful insights into the evolution of complex human society.

E.O. Wilson and "The Meaning of Human Existence"

I've just read through E.O. Wilson's new and admirably brief and terse book (~200 pages) that gives a distillation of his previous writings on our human condition, and in particular the relationship between the sciences and the humanities. I pass on here a few clips from the first section of the book, but start with his statement in the final section where he gives his version of what the meaning of human existence is. (It conforms to my own opinion that experiencing ourselves as part of biological evolution suffices as a complete spiritual path.)

So, what is the meaning of human existence? I suggest that it is the epic of the species, begun in biological evolution and prehistory, passed into recorded history, and urgently now, day by day, faster and faster into the indefinite future, it is also what we will choose to become.

From Section I "The Reason We Exist":

In ordinary usage the word “meaning” implies intention, intention implies design, and design implies a designer. Any entity, any process, or definition of any word itself is put into play as a result of an intended consequence in the mind of the designer. This is the heart of the philosophical worldview of organized religions, and in particular their creation stories. Humanity, it assumes, exists for a purpose. Individuals have a purpose in being on Earth. Both humanity and individuals have meaning.

There is a second, broader way the word “meaning” is used and a very different worldview implied. It is that the accidents of history, not the intentions of a designer, are the source of meaning. There is no advance design, but instead overlapping networks of physical cause and effect. The unfolding of history is obedient only to the general laws of the Universe. Each event is random yet alters the probability of later events. During organic evolution, for example, the origin of one adaptation by natural selection makes the origin of certain other adaptations more likely. This concept of meaning, insofar as it illuminates humanity and the rest of life, is the worldview of science.

We are about to abandon natural selection , the process that created us, in order to direct our own evolution by volitional selection— the process of redesigning our biology and human nature as we wish them to be.

Humanity, I argue, arose entirely on its own through an accumulated series of events during evolution. We are not predestined to reach any goal, nor are we answerable to any power but our own. Only wisdom based on self-understanding, not piety, will save us.

...the grand master is multilevel selection . This formulation recognizes two levels at which natural selection operates: individual selection based on competition and cooperation among members of the same group, and group selection, which arises from competition and cooperation between groups. Group selection can occur through violent conflict or by competition between groups in the finding and harvesting of new resources.

Probably ... during the habiline period, a conflict ensued between individual-level selection, with individuals competing with other individuals in the same group, on the one side, and group-level selection , with competition among groups, on the other. The latter force promoted altruism and cooperation among all the group members. It led to innate group-wide morality and a sense of conscience and honor. The competition between the two forces can be succinctly expressed as follows: Within groups selfish individuals beat altruistic individuals, but groups of altruists beat groups of selfish individuals. Or, risking oversimplification, individual selection promoted sin, while group selection promoted virtue.

So it came to pass that humans are forever conflicted by their prehistory of multilevel selection. They are suspended in unstable and constantly changing positions between the two extreme forces that created us. We are unlikely to yield completely to either force as the ideal solution to our social and political turmoil. To give in completely to the instinctual urgings born from individual selection would be to dissolve society. At the opposite extreme, to surrender to the urgings from group selection would turn us into angelic robots— the outsized equivalents of ants.

A defense of evolutionary psychology.

For those of you who follow the debate over the legitimacy of the evolutionary psychology perspective, I recommend a look at this contribution by Jerry Coyne, which features Steven Pinker responding to a critique originating from a panel at the Convergence 2013 conference (described here). whose main point was summarized by P.Z. Myers as:

Developmental plasticity is all. The fundamental premises of evo psych are false.

The response:

This paragraph disturbed me for two reasons. First, the notion that “the fundamental premises of evo psych are false” seems deeply misguided. After all, those premises boil down to this statement: some behaviors of modern humans reflect their evolutionary history. That is palpably uncontroversial, since many of our behaviors are clearly a product of evolution, including eating, avoiding dangers, and the pursuit of sex.  And since our bodies reflect their evolutionary history, often in nonadaptive ways (e.g., wisdom teeth, bad backs, the coat of hair we produce as a transitory feature in fetuses), why not our brains, which are, after all, just bits of morphology whose structure affects our behaviors?

Second, “developmental plasticity” does not stand as a dichotomous alternative to “evolved features.” Our developmental plasticity is to a large extent the product of evolution: our ability to learn language, our tendency to defer to authorities when we’re children, our learned socialization—those are all features almost certainly instilled into our brains by natural selection as a way to promote behavioral flexibility in that most flexible of mammals.

These points are followed by a list of rejoinders made by Pinker to points in the panel discussion

What are philosophers good for?

Perhaps an appropriate post for April 1st...If you are looking for a good headache, take yourself to Gary Gutting's rehashing of the "can consciousness be explained in physical terms?" debate by dragging out the classic "Mary, the color blind scientist who knows all the physical facts about colors and their perception" and the "philosophical zombie, defined as physically identical to you or me but utterly lacking in internal subjective experience." Gutting solicits comments on his article, and in a subsequent article presents a selection of the responses. From Gutting's final paragraph:

...my conclusion is that neither the Mary nor the Zombie Argument makes a decisive case against physicalism...professional philosophers have uncovered a number of subtle and complex problems for both arguments. For anyone interested in pursuing the discussion further, I would recommend the Stanford Encyclopedia of Philosophy articles “Qualia: The Knowledge Argument” (by Martine Nida-Rümelin) and “Zombies” (by Robert Kirk).

I like Metzinger's stance that consciousness is epistemologically irreducible (see his book "The Ego Tunnel"). There is one reality, one kind of fact, but two kinds of knowledge: first-person knowledge and third-person knowledge, that never can be conflated. There is a long list of ideas on why consciousness evolved, what it is good for, doing goal hierarchies and long-terms plans, enhancement of social coordination, etc. I like Metzinger's description of consciousness as a as a new kind of virtual organ - unlike the permanent hardware of the liver, kidney, or heart it is always present. Virtual organs form for a certain time when needed (like desire, courage, anger, an immune response)..."they are a new computational strategy, that makes classes of facts globally available and allows attending, flexible reacting, within context." "Reality generation" allowed animals to represent explicitly the fact that something is actually the case, the world is present. (conscious color gives information about nutritional value, red berries among green leaves, empathy gives information about the emotional state of conspecifics).

For those of you who like this sort of stuff I point out "A darwinist lynch mob goes after a philosopher" by Leon Wieseltier in the March 11 New Republic, on some outraged reactions to Nagel's new book: "Mind and Cosmos: Why the Materialist Neo-Darwinian Conception of Nature Is Almost Certainly False."

Also,"Was Wittgenstein Right? by Paul Horwich:

Wittgenstein claims that there are no realms of phenomena whose study is the special business of a philosopher, and about which he or she should devise profound a priori theories and sophisticated supporting arguments. There are no startling discoveries to be made of facts, not open to the methods of science, yet accessible “from the armchair” through some blend of intuition, pure reason and conceptual analysis. Indeed the whole idea of a subject that could yield such results is based on confusion and wishful thinking.

To which Michael Lynch makes a rejoinder.

 I have to end by repeating another old chestnut:

Philosophy, n. A route of many roads leading from nowhere to nothing. -AMBROSE BIERCE, The Devil's Dictionary

The unimaginable complexity of our evolved human systems.

In the face of all the current hubris about redesigning and engineering humans using modern genetic and biochemical tools, trying to reverse engineer brain systems that were never engineered in the first place, Randolph Nesse offers a very therapeutic essay. Here is a slightly edited version:

The products of natural selection are … not merely complicated in the way that machines are complicated, they are organically complex in ways that are fundamentally different from any product of design. This makes them difficult for human minds to fully describe or comprehend. So, we use that grand human gambit for understanding, a metaphor, in this case, the body as machine…it easy to portray the systems that mediate cell division, immune responses, glucose regulation, and all the rest, using boxes for the parts, and arrows to indicate causes what. Such diagrams summarize important information in ways we can grasp. .. But, they fundamentally misrepresent the nature of organic complexity.

Thinking about the body as a machine was a grand advance in the 16th century, when it offered an alternative to vitalism and vague notions of the life force. Now it is outmoded. It distorts our view of biological systems by fostering thinking about them as simpler and more sensibly "designed" than they are. Experts know better. They recognize that the mechanisms that regulate blood clotting are represented only crudely by the neat diagrams medical students memorize; most molecules in the clotting system interact with many others. Experts on the amygdala know that it does not have one or two functions, it has many, and they are mediated by scores of pathways to other brain loci. Serotonin exists not mainly to regulate mood and anxiety, it is essential to vascular tone, intestinal motility, and bone deposition. Leptin is not mainly a fat hormone, it has many functions, serving different ones at different time, even in the same cell. The reality of organic systems is vastly untidy. If only their parts were all distinct, with specific functions for each! Alas, they are not like machines. Our human minds have as little intuitive feeling for organic complexity as they do for quantum physics.

Recent progress in genetics confronts the problem. Naming genes according to postulated functions is as natural as defining chairs and boats by their functions. If each gene were a box on a blueprint labeled with its specific function, biology would be so much more tractable! However, it is increasingly clear that most traits are influenced by many genes, and most genes influence many traits. For instance, about 80% of the variation in human height is accounted for by genetic variation. It would seem straightforward to find the responsible genes. But looking for them has revealed that the 180 loci with the largest effects together account for only about 10% of the phenotypic variation. Recent findings in medical genetics are more discouraging. Just a decade ago, hope was high that we would soon find the variations that account for highly heritable diseases, such as schizophrenia and autism. But scanning the entire genome has revealed that there are no common alleles with large effects on these diseases. Some say we should have known. Natural selection would, after all, tend to eliminate alleles that cause disease. But, thinking about the body as a machine aroused unrealistic hopes.

The grand vision for some neuroscientists is to trace every molecule and pathway to characterize all circuits in order to understand how the brain works. Molecules, loci, and pathways do serve differentiated functions, this is real knowledge with great importance for human health. But, understanding how the brain works by drawing a diagram that describes all the components and their connections and functions is a dream that may be unfulfillable. The problem is not merely fitting a million items on a page, the problem is that no such diagram can adequately describe the structure of organic systems. They are products of miniscule changes, from diverse mutations, migration, drift, and selection, which develop into systems with incompletely differentiated parts and incomprehensible interconnections, that, nonetheless, work very well indeed. Trying to reverse engineer brain systems focuses important attention on functional significance, but it inherently limited, because brain systems were never engineered in the first place.

If bodies are not like machines, what are they like? They are more like Darwin's "tangled bank" with its "elaborately constructed forms, so different from each other, and dependent upon each other in so complex a manner." Lovely. But, can an ecological metaphor replace the metaphor of body as machine? Not likely. Perhaps someday understanding how natural selection shapes organic complexity will be so widely and deeply understood that scientists will be able to say "A body is like…a living body," and everyone will know exactly what that means.