Cognitive Evolution Research Articles

Common marmosets (Callithrix jacchus) excel in a one-trial spatial memory test, yet perform poorly in a classical memory task

When quantifying animal cognition, memory represents one of the most tested domains and is key to understanding cognitive evolution. Memory tests thus play an important role in comparative cognitive research, yet slight variations in the experimental settings can substantially change the outcome, questioning whether different memory tests tap into different memory systems or whether they test memory at all. Here, we first assessed memory performance of 16 common marmosets (Callithrix jacchus) in two distinct paradigms varying in their format and delay. First, we examined marmoset memory in a 24-h delay memory test (24 h-DMT) in which they could freely explore an environment with three novel objects of which one contained food. We examined their retention the day after, and the procedure was iterated cumulatively with previous objects remaining in the enclosure until the marmosets had to choose the correct out of 30 objects. Second, we administered a classical delayed response test (DRT) in the same animals with three objects and a maximum delay of 30 s. In the DRT, marmoset performance was poor and not better than chance after 15 s already. However, individuals excelled in the 24 h-DMT, performing above chance level after 24 h even with tenfold the number of objects to choose from compared to the DRT. Moreover, individual performances in the two tests were not correlated, and typical age effects on memory could not be detected in both experiments. Together, these results suggest that the two tests explore different domains, and that the 24 h-DMT examines long-term memory. The outcome of the DRT is more difficult to assign to memory since individuals performed only moderately even in the 0-s delay condition. This puts into question whether this task design indeed tests memory or other cognitive processes.

The Skills of Handaxe Making: Quantifying and Explaining Variability in 3D Sinuosity and Bifacial Asymmetry

Observations about handaxe techno-morphology, like their symmetry, refinement, and fine edges have long been used to reconstruct the evolution of hominin cognition, skills, and technological decision making. However, these interpretations about the cognitive and technical abilities of Acheulean hominins often rely on the most ‘beautiful’ or supposedly ‘archetypical’ looking handaxes. But how often do these finely made handaxes actually occur in assemblages and how can we identify handaxes that were more skillfully made than others? Instead of seeking to estimate the skill level of individual past knappers, a trait that is oftentimes obscured in the archaeological record, we approach the question of knapping skill from the other direction. We instead ask how much skill was required to manufacture a handaxe? We explore, not the skill level of a handaxe’s maker, but how skillfully an individual handaxe was made. We put forth a suite of novel 3D methods of handaxe analysis for calculating their 3D edge sinuosity and 3D asymmetry. Using these methods, we quantify traits that are difficult to achieve during handaxe-making, providing an estimate of the requisite amount of ability, experience, attention, and effort demanded by their manufacture. Among our large sample of handaxes from the later Acheulean of the southern Levant, we find that blank size and tool-/site-use best explain the presence of more skillfully-made handaxes. Handaxes made on larger original blanks appear to afford more volume with which to enact longer and more skillfully demanding reduction sequences. Moreover, handaxes occurring at more recurrently occupied sites demanded less skill investment and appear geared towards the more expedient fulfilment of quotidian tasks. In the later Acheulean of the southern Levant there appears to be a great diversity in how skillfully handaxes were made, likely reflecting a diversity in the goals of handaxe making.

Burning, Cleaning, Dumping, and Dissolution: Site Formation Processes and Stratigraphy of Pre‐110,000‐Year‐Old MSA l Deposits in Cave 1, Klasies River Main Site, South Africa

ABSTRACTUnderstanding the formation and stratigraphy of sequences in southern African Middle Stone Age (MSA) sites is vital for contextualizing evidence for the evolution of modern human behaviors and cognition. Deposits at these sites often have complex formation histories, typically involving a range of anthropogenic, geogenic, and biogenic depositional and post‐depositional processes, and micro‐laminated deposits are common. Consequently, archaeological micromorphology and related micro‐analyses are now routinely a major component of MSA geoarchaeological research in the region. In the past few decades, microscale studies of the formation of anthropogenic features and deposits at MSA sites have begun to provide important behavioral information, including evidence for varying occupational intensities and the structuring and maintenance of living spaces. Here, a microscale geoarchaeological approach is applied to deposits dating to the MSA I cultural phase (> 110 ka) in the Cave 1 Witness Baulk. The results show that humans played a considerable role in site formation and that subsequent diagenesis affected the guano, charcoal, ash, and shell, with particular impact on the carbonates which were variably dissolved, altered, or recrystallized. This latter process helped to preserve ash through reduced dissolution potential. Spatial and temporal patterns in these factors influence the macroscopic properties of the deposits in any particular area, with significant implications for the correlation of extant deposits across areas excavated at low resolution during the 1960s. Different, variably preserved, anthropogenic features and deposits were found to make up a significant proportion of the deposits. Inferred behaviors range from repeated long‐term low‐intensity use of individually stacked hearths to the formation of dumped deposits (including shell middens) due to repeated hearth maintenance and patterned discarding of food waste during more intensive occupations. Differences in occupational intensity and frequency both within and between the two recognized MSA I members could indicate adaptation to changing conditions as temperatures and sea levels fluctuated during Marine Isotope Stage 5e and early Stage 5d, but changes in geogenic depositional rates over the same period could skew our perception of occupational frequency. The current limited and low‐resolution dating evidence prevents correlation with any specific event/s, which might have affected behavior and/or depositional rates.

Associative learning in pairs tends to reduce individual differences in performance: An experiment with zebra finches (Taeniopygia guttata).

Associative learning in pairs tends to reduce individual differences in performance: An experiment with zebra finches (Taeniopygia guttata).

Reflections on the Role of Differentiation Processes in Forming Behavioral Phenotypes: Can These Processes Replace the Concepts of Plastic Phenotype and Reversible Plastic Phenotype?

This essay presents two lines of argument to suggest that the extension into adulthood of specific phenotypic differentiation processes, typical of early development, is fundamental to the evolution of cognition. The first of these two lines of argument is organized in three steps. The first step reviews various studies of human development, highlighting that it has slowed down throughout evolution compared to that of great apes. The second step explores the relationship between this slowed development and human cognition. The third step discusses evolutionary comparative analyses that show a correlation between the evolution of cognitive processes and developmental changes. The second line of argument examines concepts of phenotype. First, the concepts of phenotype are reviewed in correspondence to the two meanings of the word plasticity (i.e., as the ability to alternate or as the ability to shape), and it is concluded that all phenotypes -rigid, plastic, and reversible-fit the meaning of shaping. It is proposed that a phenotypical process can be seen as a continuous series of functional differentiations that occur at different times during the life of the organism and at different contextual points, both inside and outside the organism. Finally, a brief recapitulation is presented that is focused on supporting the formation of behavioral phenotypes as a sequence of differentiation processes shaping the environmental interactions from the most general to the most particular.

Developmental Bioelectricity as an Explanatory Framework for Cognition and Meaning

Abstract We critically examine the intersection of developmental bioelectricity within the context of the Peircean philosophy of science. We address the criticism of Peirce’s objective idealism and synechism, contest the conflation of semiotic and physical laws, and scrutinise Peirce’s recovery of physical from psychological laws. The upshot is a nonmechanistic, nonreductive interpretation of the evolution of cognition in the bioengineering realm. The work of Kull and others is leveraged to demarcate semiotics and physics, emphasising the irreducibility of bioelectric phenomena to mechanistic explanations. Our paper advocates for methodological synechism in evolutionary biology, highlighting the heightened roles of bioelectricity in morphogenesis and basal cognition. We propose the free-energy principle as a unifying arbiter that sets an explanatory pathway toward integrated cognition and meaning in developmental bioelectricity.

Stages and causes of the evolution of language and consciousness: A theoretical reconstruction.

Stages and causes of the evolution of language and consciousness: A theoretical reconstruction.

Form over function: Striped skunks (mephitis mephitis) learn arbitrary visual patterns to solve the slat-pulling task.

Striped skunks are omnivorous generalists with patchily distributed food-two selection pressures that are purported to drive the evolution of cognition. Despite this, the cognitive abilities of skunks have rarely been tested. Using the slat-pulling task, we assessed the ability of three striped skunks to reason about the visual patterns of support when two slats were presented (one supporting a food item). We used both functional slats (real wooden slats that gave subjects both visual and functional information when manipulated) and purely representational slats in an arbitrary version of the task (painted lines that provided only visual information). All three skunks found the arbitrary task difficult to learn but nevertheless learned to solve it after thousands of trials. They appeared to respond to visual patterns of contact and perceptual containment between food and painted lines to solve several configurations of the task. Interestingly, only one of three skunks learned to pull supportive over unsupportive slats (despite the addition of functional information). This subject had first learned the visual pattern associated with reward in the arbitrary version, thus showing the transfer of visual patterns from the arbitrary to the functional task. Overall, striped skunks demonstrated the ability to use visual patterns to solve problems despite their relatively poor vision and difficulty in learning the tasks. These findings provide further support for the idea that slat-pulling tasks can be solved by visual pattern learning alone and that this possibility needs to be controlled for in tasks assessing abstract causal reasoning. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Pair-bond strength is consistent and related to partner responsiveness in a wild corvid.

The need to maintain strong social bonds is widely thought to be a key driver of cognitive evolution. Cognitive abilities to track and respond to information about social partners may be favoured by selection if they vary within populations and confer fitness benefits. Here we evaluate four key assumptions of this argument in wild jackdaws (Corvus monedula), corvids whose long-term pair bonds exemplify one of the putative social drivers of cognitive evolution in birds. Combining observational and experimental behavioural data with long-term breeding records, we found support for three assumptions: (i) pair-bond strength varies across the population, (ii) is consistent within pairs over time and (iii) is positively associated with partner responsiveness, a measure of socio-cognitive performance. However, (iv) we did not find clear evidence that stronger pair bonds lead to better fitness outcomes. Strongly bonded pairs were better able to adjust hatching synchrony to environmental conditions but they did not fledge more or higher quality offspring. Together, these findings suggest that maintaining strong pair bonds is linked to socio-cognitive performance and may facilitate effective coordination between partners. However, they also imply that these benefits are insufficient to explain how selection acts on social cognition. We argue that evaluating how animals navigate trade-offs between investing in long-term relationships versus optimizing interactions in their wider social networks will be a crucial avenue for future research.

Exploring sex differences in Alzheimer’s disease: a comprehensive analysis of a large patient cohort from a memory unit

BackgroundAlzheimer’s disease (AD) stands as the leading cause of dementia worldwide, and projections estimate over 150 million patients by 2050. AD prevalence is notably higher in women, nearly twice that of men, with discernible sex differences in certain risk factors. To enhance our understanding of how sex influences the characteristics of AD patients and its potential impact on the disease trajectory, we conducted a comprehensive analysis of demographic, clinical, cognitive, and genetic data from a sizable and well-characterized cohort of AD dementia patients at a memory clinic in Barcelona, Spain.MethodsThe study cohort comprised individuals with probable and possible AD dementia with a Clinical Dementia Rating (CDR) score between 1 and 3 diagnosed at the Memory Unit from Ace Alzheimer Center Barcelona, Spain, between 2008 and 2018. We obtained cognitive baseline data and follow up scores for the Mini-Mental State Examination (MMSE), the CDR scale, and the neuropsychological battery used in our center (NBACE). We employed various statistical techniques to assess the impact of sex on cognitive evolution in these dementia patients, accounting for other sex-related risk factors identified through Machine Learning methods.ResultsThe study cohort comprised a total of 6108 individuals diagnosed with AD dementia during the study period (28.4% males and 71.6% females). MMSE scores exhibited an average decline of approximately two units per year, unaffected by sex. Similarly, the decline in most neuropsychological functions assessed by NBACE did not exhibit significant differences between males and females. However, we observed that women diagnosed with mild AD dementia progressed more rapidly based on their CDR score (HR = 2.57, 95%CI:2.33–2.84) than men (HR = 2.03, 95%CI: 1.71–2.41) (p-interaction = 0.01).ConclusionsOur findings do not strongly support the notion that sex significantly modifies the clinical progression of AD dementia based on cognitive data. Further research is essential to validate whether women with mild AD dementia indeed progress more rapidly than men at a similar stage and to delve into the potential underlying reasons for this finding.

Метаморфозы идентичности человека достроенного: от цифрового донора к цифровому кентавру

<p style="text-align: justify;"><strong>Objective. </strong>Identification of formation vectors of technologically completed personality and analysis of the specificity of identity of its different types through the prism of opportunities and risks of its construction.<br><strong>Background. </strong>The Fourth Industrial Revolution is gradually bringing us to the frontier of the steady transformation of the human being into a being increasingly connected to technology. Smartphones, computers, the Internet of Things, and AI assistants, which form an integral technosystem that mediates the everyday life of man, are complex cultural tools that become his complements and extensions – part of the personality. A new type of personality, technologically completed by advanced digital tools, is formed as the most important result of the modern stage of social and cognitive evolution of the human psyche in the conditions of digital transformations. Identity as an integrative personal formation is a key phenomenon for understanding the possible psychological transformations of a modern person in the conditions of convergence of online and offline worlds and determining the risks of various options of metamorphoses of technologically completed personality. <br><strong>Methodology. </strong>Externalist approaches to the study of a person (L.S. Vygotsky, E. Clark, D. Chalmers, L. Malafouris, etc.), the socio-cognitive concept of digital socialization (G.U. Soldatova, A.E. Voyskunsky), concepts and approaches to the analysis of identity (E. Erikson, K. Rogers, I. Hoffman, G. Tajfel, J. Turner, S. Moscovici, J. Marcia, etc.). <br><strong>Conclusions. </strong>The vectors of technologically extended personality are identified through the following types: digital natives, techno-conservatives, techno-isolationists, cyborgs, personoids, digital centaurs. Their main characteristics are described and the specifics of identity and possible risks of its development for each type are analyzed. One of the pre-adaptive vectors of identity transformation is the transition from digital natives-donors to digital centaurs.</p>

The social cognitive evolution of myths: Collective narratives of shared pasts as markers for coalitions' communicative and cooperative prowess.

To understand why humans put much effort into celebrating cultural myths, it is crucial to approach this phenomenon as part of humans' broader social cognitive evolution. Specifically, humans' unique capacity to bond with others through shared/collective representations of shared experiences has likely caused individuals to use myths to assess not only coalitions' fitness interdependence, but also their cooperative prowess.

Don't ignore cognitive evolution during the three million years that preceded the archaeological record of material culture!

The target article rightly questions whether the archaeological record is useful for identifying sea changes in hominin cognitive abilities. This commentary suggests an alternative approach of synthesizing findings from primatology, evolutionary developmental biology, and paleoanthropology to formulate hypotheses about cognitive evolution in hominins that lived during the three million years that preceded the record of material culture (the Botanic Age).

"Non-Reliance on Words" in Ancient and Modern Contexts: Cognitive Evolution from Illiteracy to the Information Age

"Non-Reliance on Words" in Ancient and Modern Contexts: Cognitive Evolution from Illiteracy to the Information Age

Material culture both reflects and causes human cognitive evolution.

Our commentary suggests that different materialities (fragile, enduring, and mixed) may influence cognitive evolution. Building on Stibbard-Hawkes, we propose that predictive brains minimise errors and seek information, actively structuring environments for epistemic benefits. This perspective complements Stibbard-Hawkes' view.

Archaeology retains a central role for studying the behavioral and cognitive evolution of our species and genus.

Our species' behavioral and cognitive evolution constitute a key research topic across many scientific disciplines. Based on ethnographic hunter-gatherer data, Stibbard-Hawkes challenges the common link made between past material culture and cognitive capacities. Despite this adequate criticism, archaeology must retain a central role for studying these issues due to its unique access to relevant empirical evidence in deep time.

From reactions to reflection: A recursive framework for the evolution of cognition and complexity.

From reactions to reflection: A recursive framework for the evolution of cognition and complexity.

Action observation reveals a network with divergent temporal and parietal cortex engagement in dogs compared with humans

Abstract Action observation is a fundamental pillar of social cognition. Neuroimaging research has revealed a human and non-human primate action observation network (AON) encompassing frontotemporoparietal areas with links to the species’ imitation tendencies and relative lobe expansion. Dogs (Canis familiaris) have good action perception and imitation skills and a less expanded parietal than temporal cortex, but their AON remains unexplored. We conducted a functional MRI study with 28 dogs and 40 humans and found functionally analogous involvement of somatosensory and temporal brain areas of both species’ AONs and responses to transitive and intransitive action observation in line with their imitative skills. Employing a functional localizer, we also identified functionally analogous agent-responsive areas within both species’ AONs. However, activation and task-based functional connectivity measures suggested significantly less parietal cortex involvement in dogs than in humans. These findings advance our understanding of the neural bases of action understanding and the convergent evolution of social cognition, with analogies and differences resulting from similar social environments and divergent brain expansion, respectively.

Wild chimpanzees remember and revisit concealed, underground army ant nest locations throughout multiple years

Chimpanzees use spatiotemporal cognition for fruit foraging by remembering tree locations and fruiting seasons. However, the spatiotemporal cognition behind exploiting other foods has rarely been studied. Here, we investigate whether chimpanzees use memory to exploit concealed, underground army ant nests. We analyse 679 chimpanzee visits to four nests recorded during five years (2018–2022) using camera traps in a savanna habitat. We explore if chimpanzees intentionally revisit nests, study how they detect ants, and assess ant availability and chimpanzee ant consumption. Nests are concealed, scarce, and intermittently reoccupied, yet chimpanzees eat ants frequently. We find that out of 34 identified chimpanzees who visit the nests, 23 revisit at least one. Chimpanzees visit nest sites significantly more often than similar sites without nests. Individuals revisit significantly sooner and inspect significantly longer nests where they have more recently encountered ants. The apes use sight, smell, taste, touch, and probing tools, to detect ants inside nests. We provide the first evidence suggesting that chimpanzees use spatial and episodic-like memory to exploit concealed social insects throughout multiple years. Our results expand our understanding of the cognitive strategies behind chimpanzee insectivory, suggesting it may have played an important role in the evolution of primate spatiotemporal cognition.

Lessons for Theory from Scientific Domains Where Evidence is Sparse or Indirect.

In many scientific fields, sparseness and indirectness of empirical evidence pose fundamental challenges to theory development. Theories of the evolution of human cognition provide a guiding example, where the targets of study are evolutionary processes that occurred in the ancestors of present-day humans. In many cases, the evidence is both very sparse and very indirect (e.g., archaeological findings regarding anatomical changes that might be related to the evolution of language capabilities); in other cases, the evidence is less sparse but still very indirect (e.g., data on cultural transmission in groups of contemporary humans and non-human primates). From examples of theoretical and empirical work in this domain, we distill five virtuous practices that scientists could aim to satisfy when evidence is sparse or indirect: (i) making assumptions explicit, (ii) making alternative theories explicit, (iii) pursuing computational and formal modelling, (iv) seeking external consistency with theories of related phenomena, and (v) triangulating across different forms and sources of evidence. Thus, rather than inhibiting theory development, sparseness or indirectness of evidence can catalyze it. To the extent that there are continua of sparseness and indirectness that vary across domains and that the principles identified here always apply to some degree, the solutions and advantages proposed here may generalise to other scientific domains.