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The Origin of Non-biological ‘Paralife’ and its Coevolution with Biological Intelligence

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Abstract

When animals evolve sufficient intelligence and dexterity to be able to learn to fabricate utility products (UPs) like tools, the UP's they produce become part of an induced-reproduction system that intrinsically shares many life-like traits with biological organisms, including genome-like fabrication and operation information that is physically-encoded in the animal fabricator’s neural networks. When this set of life- like traits includes a sufficient capacity for system-improving cultural evolution (UP-evolvability), the UPs become ‘para-alive’, i.e., nearly alive, or a form of non-biological UP-paralife that is equivalent to the life- status of biological viruses, plasmids, and transposons. In the companion paper I focus on the evolution of UP-paralife in the context of modern, language-capable humans and its predicted evolution going forward in time (Rice 2022). Here I look backward in time and focus on the origin of UP-paralife and its subsequent coevolution with human intelligence. I begin by determining the pathways leading to the evolution of large brains in the rare lineages of biological life that have sufficient intelligence to learn to fabricate tools –a critical first step in the evolution of UP-paralife. The simplest forms of these learning- based UPs, made by species like chimpanzees and New Caledonian crows, represent only proto-UP- paralife because they lack sufficient UP-evolvability. Expanded UP-evolvability required a combination of three attributes that enabled continuous niche-expansion of the animal fabricator via a new and advanced form of UP-mediated teamwork (TW): i) self-domestication that facilitated TW among low-related individuals, ii) learned volitional words (protolanguage) that represent ephemeral UPs that coordinate TW, and iii) learned fabrication of simple flaked-stone tools with cutting and chopping capabilities (a UP to make other structural UPs) that expanded teammate phenotypes and TW capabilities. This specific triad of attributes is synergistic because each one acts as a TW-enhancer that can gradually erode different components of the three major constraints on TW operation and expansion: too much selfishness, insufficient coordination signals, and insufficient physical traits of teammates. The increase in UP- evolvability was transformative and marked the origin of UP-paralife and the initiation of coevolution between UP-paralife (cultural evolution) and the intelligence of its hominin/human symbiont (genetic evolution) that fostered 2.5 million years of: i) continuous brain size increase and niche-expansion within the genus Homo, and ii) parallel advances in the diversity, complexity and uses of UP-paralife. This coevolution also fostered evolutionary expansion of word-based communication, and eventually language, that acted in a catalyst-like manner to facilitate the evolution of increasingly complex forms of imagination, reasoning, mentalizing, and UP-generating technology. I next focus on the evolution of creativity in the human lineage –in the form of divergent thinking and creative imagination. I conclude that the evolution of this advanced cognitive feature required a preadaptation of sufficient intelligence and is the component of human cognition that was the major causal factor generating the greatly expanded diversity and complexity of UP-paralife currently associated with modern humans. Lastly, I apply my findings to the issue of the prevalence of extraterrestrial intelligent life. I conclude that any exoplanets with detected chemical life will very rarely (e.g., probability ~10-5 for a planet closely matching Earth’s characteristics) have evolved intelligence equalling or exceeding that of humans.

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The neural substrate of memory The ability to form memory is an essential trait that allows learning and the accumulation of knowledge. But what is a memory? There has been a long history of searching for the neuronal substrate that forms memory in the brain, and the emerging view is that ensembles of engram cells explain how memories are formed and retrieved. In a Review, Josselyn and Tonegawa discuss the evidence for engram cells as a substrate of memory, particularly in rodents; what we have learned so far about the features of memory, including memory formation, retrieval over time, and loss; and future directions to understand how memory becomes knowledge. Science , this issue p. eaaw4325
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Creativity plays an important role in human society as well as in individual development, and creativity in the domain of science is a specific form. A body of research had demonstrated the role of divergent thinking in creativity. The role of convergent thinking had also been recognized, but more empirical evidence was needed. To investigate the interaction between convergent and divergent thinking on adolescent scientific creativity, the current study tested 588 high school students. The results showed that convergent thinking interacted with fluency/flexibility of divergent thinking on scientific creativity. In particular, divergent thinking predicted creativity in those high in convergent thinking. Findings suggested a threshold-setting effect of convergent thinking, which meant only when convergent thinking capacity reached a certain level, divergent thinking could play a role in scientific creativity. Implications for future research and educational practice were discussed.
Article
When we open our eyes, we see a world filled with objects and events. Yet, due to occlusion of some objects by others, we only have partial perceptual access to the events that transpire around us. I discuss the body of research on mental imagery in animals. I first cover prior studies of mental rotation in pigeons and imagery using working memory procedures first developed for human studies. Next, I discuss the seminal work on a type of learning called mediated conditioning in rats. I then provide more in-depth coverage of work from my lab suggesting that rats can use imagery to fill in missing details of the world that are expected but hidden from perception. We have found that rats make use of an active expectation (i.e., an image) of a hidden visual event. I describe the behavioral and neurobiological studies investigating the use of a mental image, its theoretical basis, and its connections to current human cognitive neuroscience research on episodic memory, imagination, and mental simulations. Collectively, the reviewed literature provides insight into the mechanisms that mediate the flexible use of an image during ambiguous situations. I position this work in the broader scientific and philosophical context surrounding the concept of mental imagery in human and nonhuman animals.
Article
Phylogenetic relationships among hominins provide a necessary framework for assessing their evolution. Reconstructing these relationships hinges on the strength of the character data analyzed. The phylogenetic position of Ardipithecus ramidus is critical to understanding early hominin evolution, and while many accept that it is most likely the sister taxon to all later hominins, others have argued that Ar. ramidus was ancestral to Pan. Although the study by Strait and Grine (2004) suggested the former, available evidence permitted only 26% of characters in their matrix to be assessed for Ar. ramidus. Fossils described subsequently by Suwa, White and colleagues in 2009 have enabled the number of characters that can be coded for this species to be expanded to 78% of the matrix. Here, we incorporate these new character data to evaluate their impact on the phylogenetic relationships of Ar. ramidus. Moreover, we have further revised the Strait and Grine (2004) matrix as necessitated by additions to the hypodigms of other fossil taxa. This updated matrix was analyzed using both parsimony and Bayesian techniques in a sequence of four iterative steps to independently evaluate the impact of matrix and expanded character revisions on tree topology. Despite the new data and matrix revisions, tree topology has remained remarkably stable. The addition of new craniodental material has served to markedly strengthen the support for the placement of Ar. ramidus as being derived relative to Sahelanthropus, and as the sister taxon of all later hominins. These findings support the phylogenetic hypothesis originally proposed by White and colleagues in 1994. This updated matrix provides a basis for the assessment of additional extinct species.
Article
Systematic, broad phylogenetic comparisons of diverse cognitive abilities are essential to understand cognitive evolution. Few studies have examined multiple skills comparatively, using identical tasks across species. Previous research centered on primates, but recent evidence suggests that complex cognition may have evolved in distantly related taxa. We administered the tasks of the primate cognition test battery (PCTB) to 4 parrot species for a first direct comparison with primates. The parrots did not perform significantly worse than the previously tested primates in all but one of the test scales, but remained at chance levels throughout. Chimpanzees outperformed them in the physical but not the social domain. No differences between the domains nor across the parrot species were detected. It remains questionable whether the chance level performance reflects the parrots’ cognitive capacity or results from task constraints, which would limit the suitability of PCTB for phylogenetic comparisons. Possible implications for the field are discussed.
Article
A set of frontoparietal brain regions - the multiple-demand (MD) system [1, 2] - has been linked to fluid intelligence in brain imaging [3, 4] and in studies of patients with brain damage [5-7]. For example, the amount of damage to frontal or parietal, but not temporal, cortices predicts fluid intelligence deficit [5]. However, frontal and parietal lobes are structurally [8] and functionally [9, 10] heterogeneous. They contain domain-general regions that respond across diverse tasks [11, 12], but also specialized regions that respond selectively during language processing [13]. Since language may be critical for complex thought [14-24, cf. 25-26], intelligence loss following damage to frontoparietal cortex could have important contributions from damage to language-selective regions. To evaluate the relative contributions of MD vs. language-selective regions, we employed large fMRI datasets to construct probabilistic maps of the two systems. We used these maps to weigh the volume of lesion (in each of 80 patients) falling within each system. MD-weighted, but not language-weighted, lesion volumes predicted fluid intelligence deficit (with the opposite pattern observed for verbal fluency), suggesting that fluid intelligence is specifically tied to the MD system, and undermining claims that language is at the core of complex thought.
Article
A long-term collaborative study by palaeolithic archaeologists and cognitive psychologists has continued in its investigations into the stone tool-making and tool-using abilities of a captive bonobo (a 180 pound male, named Kanzi, aged 12 years at the time of experiments reported here). A major focus of this study has been examination of the lithic reduction strategy over time and detailed analysis of the artefacts Kanzi has produced in 2 years of experimentation since our original report. Kanzi has exhibited marked improvement in his stone-working skills, although to date the artefacts he has produced still contrast with early hominid-produced artefacts in a number of attributes. Statistical analysis revealed that Kanzi is clearly preferentially selecting larger, heavier pieces of debitage (flakes and fragments) for use as tools. 1999 Academic Press
Article
Language serves as a cornerstone of human cognition. However, our knowledge about its neural basis is still a matter of debate, partly because 'language' is often ill-defined. Rather than equating language with 'speech' or 'communication', we propose that language is best described as a biologically determined computational cognitive mechanism that yields an unbounded array of hierarchically structured expressions. The results of recent brain imaging studies are consistent with this view of language as an autonomous cognitive mechanism, leading to a view of its neural organization, whereby language involves dynamic interactions of syntactic and semantic aspects represented in neural networks that connect the inferior frontal and superior temporal cortices functionally and structurally.
Article
Owl monkeys (genus Aotus) are the only taxon in simian primates that consists of nocturnal or otherwise cathemeral species. Their night vision is superior to that of other monkeys, apes, and humans but not as good as that of typical nocturnal mammals. This incomplete night vision has been used to conclude that these monkeys only secondarily adapted to a nocturnal lifestyle, or to their cathemeral lifestyle that involves high night-time activity. It is known that the rod cells of many nocturnal mammals possess a unique nuclear architecture in which heterochromatin is centrally located. This "inverted nuclear architecture", in contrast with "conventional nuclear architecture", provides elevated night vision by passing light efficiently to the outer segments of photo-receptors. Owl monkey rod cells exhibit an intermediate chromatin distribution, which may provide them with less efficient night vision than other nocturnal mammals. Recently, we identified three megasatellite DNAs in the genome of Azara's owl monkey (Aotus azarae). In the present study, we show that one of the three megasatellite DNAs, OwlRep, serves as the primary component of the heterochromatin block located in the central space of the rod nucleus in A. azarae. This satellite DNA is likely to have emerged in the Aotus lineage after its divergence from those of other platyrrhini taxa and underwent a rapid expansion in the genome. Our results indicate that the heterochromatin core in the A. azarae rod nucleus was newly formed in A. azarae or its recent ancestor, and supports the hypothesis that A. azarae, and with all probability other Aotus species, secondarily acquired night vision.
Article
Apes, corvids, and pigeons differ in their pallial/cortical neuron numbers, with apes ranking first and pigeons third. Do cognitive performances rank accordingly? If they would do, cognitive performance could be explained at a mechanistic level by computational capacity provided by neuron numbers. We discuss five areas of cognition (short-term memory, object permanence, abstract numerical competence, orthographic processing, self-recognition) in which apes, corvids, and pigeons have been tested with highly similar procedures. In all tests apes and corvids were on par, but also pigeons reached identical achievement levels in three tests. We suggest that higher neuron numbers are poor predictors of absolute cognitive ability, but better predict learning speed and the ability to flexibly transfer rules to novel situations.
Article
Hymenoptera (sawflies, wasps, ants, and bees) are one of four mega-diverse insect orders, comprising more than 153,000 described and possibly up to one million undescribed extant species. As parasitoids, predators, and pollinators, Hymenoptera play a fundamental role in virtually all terrestrial ecosystems and are of substantial economic importance. To understand the diversification and key evolutionary transitions of Hymenoptera, most notably from phytophagy to parasitoidism and predation (and vice versa) and from solitary to eusocial life, we inferred the phylogeny and divergence times of all major lineages of Hymenoptera by analyzing 3,256 protein-coding genes in 173 insect species. Our analyses suggest that extant Hymenoptera started to diversify around 281 million years ago (mya). The primarily ectophytophagous sawflies are found to be monophyletic. The species-rich lineages of parasitoid wasps constitute a monophyletic group as well. The little-known, species-poor Trigonaloidea are identified as the sister group of the stinging wasps (Aculeata). Finally, we located the evolutionary root of bees within the apoid wasp family "Crabronidae." Our results reveal that the extant sawfly diversity is largely the result of a previously unrecognized major radiation of phytophagous Hymenoptera that did not lead to wood-dwelling and parasitoidism. They also confirm that all primarily parasitoid wasps are descendants of a single endophytic parasitoid ancestor that lived around 247 mya. Our findings provide the basis for a natural classification of Hymenoptera and allow for future comparative analyses of Hymenoptera, including their genomes, morphology, venoms, and parasitoid and eusocial life styles.
Article
In this paper we analyse the possibility that the early hominin Ardipithecus ramidus had vocal capabilities far exceeding those of any extant non-human primate. We argue that erect posture combined with changes in craniofacial morphology, such as reduced facial and jaw length, not only provide evidence for increased levels of pro-sociality, but also increased vocal ability. Reduced length of the face and jaw, combined with a flexed cranial base, suggests the larynx in this species was situated deeper in the neck than in chimpanzees, a trait which may have facilitated increased vocal ability. We also provide evidence that Ar. ramidus, by virtue of its erect posture, possessed a degree of cervical lordosis significantly greater than chimpanzees. This is indicative of increased mobility of the larynx within the neck and hence increased capacity to modulate vocalisations. In the paleoanthropological literature, these changes in early hominin skull morphology have to date been analysed in terms of a shift in mating and social behaviour, with little consideration given to vocally mediated sociality. Similarly, in the literature on language evolution there is a distinct lacuna regarding links between craniofacial correlates of social and mating systems and vocal ability. These are surprising oversights given that pro-sociality and vocal capability require identical alterations to the common ancestral skull and skeletal configuration. We therefore propose a model which integrates data on whole organism morphogenesis with evidence for a potential early emergence of hominin socio-vocal adaptations. Consequently, we suggest vocal capability may have evolved much earlier than has been traditionally proposed. Instead of emerging in the Homo genus, we suggest the palaeoecological context of late Miocene and early Pliocene forests and woodlands facilitated the evolution of hominin socio-vocal capability. We also propose that paedomorphic morphogenesis of the skull via the process of self-domestication enabled increased levels of pro-social behaviour, as well as increased capacity for socially synchronous vocalisation to evolve at the base of the hominin clade.
Article
Self-deception is both commonplace and costly, which raises the question of what purpose it might serve. According to the dominant explanation in psychology and economics, self-deception is an intrapersonal process that fortifies and protects the self from threatening information. An alternative possibility is that self-deception evolved as an interpersonal strategy to persuade others. To investigate interpersonal aspects of self-deception, we gave people a persuasive task and measured their information processing biases and their persuasiveness. Results revealed that people who were financially motivated to persuade another person in a particular direction demonstrated a self-deceptive information processing bias consistent with their persuasive goals. This information processing bias led people to convince themselves of the veracity of their persuasive goal, and subsequently to be more persuasive to others. These findings suggest that self-deception has interpersonal benefits that offset its costs.
Article
Natural selection, as both a process and a scientific concept, is eloquently simple. Unfortunately, this simplicity sometimes belies Darwin’s broader view of evolution as a multifaceted process that proceeds from both ecological pressures and phylogenetic history. Darwin further understood that it is not just physical traits that are transmitted generationally, but also behavioural patterns, both of which are subject to the shaping influences of environment and phylogeny. Chimpanzees, bonobos and humans are the most carnivorous extant primates, an observation that serves as the basis of our extended argument that vertebrate predation is a synapomorphy of these sister taxa. From there, we use archaeological data to trace the inferred polarity of hominin carcass foraging and meat-eating from their first archaeological indications ∼2.6 million years ago (Mya). A review of the early Pleistocene African record demonstrates that taphonomic evidence of a hominin predatory/meat-eating behavioral module clarifies ∼2.0 Mya, a critical time period characterised by traces of advanced carcass foraging, which, in turn, suggest that an earlier phase(s) of vertebrate capture by hominins was/were simpler. In rounding out this meta-analytical consideration of hominin carnivory, we draw on comparative primatology, ecology and archaeology in order to build a holistic model of this fundamental behavioural adaptation.
Article
This paper presents results of almost 30 years of study of the cognitive and communicative activities of Grey parrots (Psittacus erithacus), conventionally regarded as mindless mimics. These studies have demonstrated that Grey parrots can solve various cognitive tasks and acquire and use English speech in ways that often resemble those of very young children. Examples include the concepts of same/different, colour, size and shape. The parrot Alex can also recognize and distinguish numbers up to six, and spontaneously demonstrated his ability to grasp the concept of "none". Given the evolutionary distance between birds and mammals, these results have intriguing implications for the evolution of intelligence, the study of comparative intelligence, and the care and maintenance of birds held in captivity in zoos and as companion animals. (c) 2006 Elsevier B.V. All rights reserved.
Chapter
Humans place great significance in intellectual abilities, and because of this, biologists have been interested in the cognitive abilities of animals since Aristotle. The difficulties in defining intelligence in a way that can be applied to taxonomically distant animals have resulted in most studies using relative brain size as a directly measurable metric of intelligence. This approach has received criticism but persists in the literature as it has proved to be informative despite imperfections. Large brain size and, by inference, arguably complex cognition have evolved independently in several lineages including primates, corvids, cetaceans, cephalopods and hymenopteran insects. In these varying taxa, the evolutionary history of intelligence is still hotly debated. Proponents of the social intelligence hypothesis suggest that the cognitive challenges of group living have driven the evolution of large brains whereas other researchers have suggested ecological drivers such as seasonal challenges, dietary differences and energetic constraints. Here I review the study of the evolution of intelligence with particular focus on the widely cited social intelligence hypothesis and cognitive buffering hypothesis. I begin by summarising the study of animal intelligence and the methods employed. I will then go on to briefly review the current state of knowledge concerning cognitive evolution in some of the most heavily studied taxa. Finally, I will summarise and evaluate the social intelligence hypothesis and the cognitive buffering hypothesis. I propose that the weight of evidence suggests that social intelligence is limited to relatively few taxa, such as primates and cetaceans, and that across other taxa, a variety of other factors have driven the evolution of advanced intelligence in animals.
Article
In the past five years, two exceptional discoveries have been made—the Dikika modified bones and the Lomekwi stone tools. If genuine, they would change current views on human evolution by showing that Pliocene hominins were involved in stone tool use and meat-eating more than 3 million years ago. These paradigm-changing discoveries require solid, unambiguous evidence. Here, we adopt a hypothesis-testing scientific approach in which we show that neither of these discoveries, as reported, has provided compelling evidence of these behaviors in the Pliocene. We do not reject the hypothesis of stone tool use and butchery in the Pliocene. We do however stress that the evidence presented in both cases remains disputable and the inferences drawn from it are not secure. We argue that the hypotheses of non-hominin agency for the Dikika bones and the ex situ nature of the Lomekwi assemblage (probably involving a palimpsest of accumulations) have not been discarded.
Article
This article extends the previous studies on the relationship between intelligence and creativity by providing a new methodology and an empirical test of the hypothesis that intelligence is a necessary condition for creativity. Unlike the classic threshold hypothesis, which assumes the existence of a curvilinear relationship between intelligence and creativity, the Necessary Condition Analysis (Dul, 2016) focuses on and quantifies the overall shape of the relationship between intelligence and creativity. In eight studies (total N = 12,255), using different measures of intelligence and creativity, we observed a consistent pattern that supports the necessary-but-not-sufficient relationship between these two constructs. We conclude that although evidence concerning the threshold hypothesis on the creativity–intelligence relationship is mixed, the “necessary condition hypothesis” is clearly corroborated by the results of appropriate tests.
Article
The origins of the genus Homo are murky, but by H. erectus, bigger brains and bodies had evolved that, along with larger foraging ranges, would have increased the daily energetic requirements of hominins. Yet H. erectus differs from earlier hominins in having relatively smaller teeth, reduced chewing muscles, weaker maximum bite force capabilities, and a relatively smaller gut. This paradoxical combination of increased energy demands along with decreased masticatory and digestive capacities is hypothesized to have been made possible by adding meat to the diet, by mechanically processing food using stone tools, or by cooking. Cooking, however, was apparently uncommon until 500,000 years ago, and the effects of carnivory and Palaeolithic processing techniques on mastication are unknown. Here we report experiments that tested how Lower Palaeolithic processing technologies affect chewing force production and efficacy in humans consuming meat and underground storage organs (USOs). We find that if meat comprised one-third of the diet, the number of chewing cycles per year would have declined by nearly 2 million (a 13% reduction) and total masticatory force required would have declined by 15%. Furthermore, by simply slicing meat and pounding USOs, hominins would have improved their ability to chew meat into smaller particles by 41%, reduced the number of chews per year by another 5%, and decreased masticatory force requirements by an additional 12%. Although cooking has important benefits, it appears that selection for smaller masticatory features in Homo would have been initially made possible by the combination of using stone tools and eating meat.
Article
Language is a unique form of communication in humans and is unmatched in the animal kingdom. There are well-defined cortical regions involved in both the comprehension and production of speech including Wernicke's and Broca's area. To what extent these regions play a role in the communicative abilities of primates, notably great apes, remains a central topic of research in neuroscience, anthropology, and psychology. In this chapter, I present an overview of the cognitive foundations of gestural and vocal communication in chimpanzees, including some results from language-trained apes. I also present data on the evolution in size and lateralization of Wernicke's and Broca's area in chimpanzees. These anatomical data are combined with behavioral data to show how individual differences in gestural and vocal communication are associated with volumetric and lateralized differences in Broca's and Wernicke's areas. The collective findings are discussed within the context of language evolution and the emergence of complex motor and cognitive processes in humans after the split from the common ancestor with chimpanzees. © 2013 Springer Science+Business Media New York. All rights are reserved.
Article
Positive associations between human intelligence and brain size have been suspected for more than 150 years. Nowadays, modern non-invasive measures of in vivo brain volume (Magnetic Resonance Imaging) make it possible to reliably assess associations with IQ. By means of a systematic review of published studies and unpublished results obtained by personal communications with researchers, we identified 88 studies examining effect sizes of 148 healthy and clinical mixed-sex samples (> 8,000 individuals). Our results showed significant positive associations of brain volume and IQ (r=.24, R(2)=.06) that generalize over age (children vs. adults), IQ domain (full-scale, performance, and verbal IQ), and sex. Application of a number of methods for detection of publication bias indicates that strong and positive correlation coefficients have been reported frequently in the literature whilst small and non-significant associations appear to have been often omitted from reports. We show that the strength of the positive association of brain volume and IQ has been overestimated in the literature, but remains robust even when accounting for different types of dissemination bias, although reported effects have been declining over time. While it is tempting to interpret this association in the context of human cognitive evolution and species differences in brain size and cognitive ability, we show that it is not warranted to interpret brain size as an isomorphic proxy of human intelligence differences.