Center for Behavior, Evolution, and Culture

Stephan Kaufhold, UCSD. Title: Situated Simian Minds: Why Context Matters for Modeling Primate Behavior
2025-09-29 12:00 - 13:30 (America/Los_Angeles) | 352 Haines Hall
Unlike humans, who can maintain relationships and communities beyond temporal and spatial boundaries, nonhuman primates’ relationships are fundamentally grounded in embodied, immediate interactions. In this talk, I present two empirical studies on resource conflicts in semi-naturalistic primate groups, showing how their behavior and decision-making are best understood by considering social and ecological contexts.
The first study examines food transfers in socially housed orangutans. We found that transfer strategies (e.g., taking, co-feeding, requesting) are not independent events, but dynamically calibrated by preceding interactions within dyads.
The second study investigates social tolerance in Japanese macaques, using a hybrid computer vision approach to quantify how monkeys socially navigate in the presence of food resources. Macaques maintained greater-than-chance distances from conspecifics when entering a food-baited circle inside their enclosures. This was especially evident in subordinate males, who took more circuitous routes and maximized their distance from others when approaching the resource in the presence of alpha males. Our results show how macaques’ movement trajectories are socially situated and balance social risk with resource access.
I conclude by discussing how a relational, situated approach is particularly important when designing machine learning datasets in primate research. By grounding models in function and context, we can advance our understanding of primate behavior and communication and avoid pitfalls of projecting human frameworks onto other species.
For more about Stephan’s work see his website:
https://www.stephankaufhold.com/
Zoom link for those unable to attend in person:
https://ucla.zoom.us/j/94308730584?pwd=[REDACTED]
Meeting ID: 943 0873 0584
Passcode: [REDACTED]

Stacy Rosenbaum (Univ. Michigan) - "The long arm of “childhood:” what can other primates teach us about the early life origins of aging and resiliency?"
2025-10-20 12:00 - 13:30
Early life experiences are widely thought to shape adult behavior, health, and fitness across the tree of life. The deep evolutionary roots of these “early life effects”—seen in organisms ranging from plants to primates—have sparked considerable interest in their biological underpinnings. While individual variation in responses to early life adversity is well recognized, new research suggests that species-level differences may also be considerable. In this talk, I present longitudinal data from wild savannah baboons and mountain gorillas showing that similar forms of early life adversity can have dramatically different outcomes depending on the species. I explore the socioecological factors that may drive this variation and discuss how these insights can inform our broader understanding of aging and resilience in primates, including humans.

Change of plans: Our speaker will not be able to attend in person and will give her talk via Zoom.
Enrolled students are still expected to attend in person to watch the zoom presentation together (in 352 Haines Hall). We will still have individual meetings between the speaker and students.
https://ucla.zoom.us/j/94308730584?pwd=[REDACTED]
Meeting ID: 943 0873 0584
Passcode: [REDACTED]

Richard Karban (UC-Davis) - Plant Communication and Individual Personalities
2025-11-03 12:00 - 13:30
This talk will attempt to answer three questions: 1) Do plants communicate about their risk of herbivory? 2) Do plants have individual personalities with respect to communication? 3) Why does this matter?
Biologists have known for a long time that plants sense their environments and respond accordingly, i.e., they exhibit “behavior.” Whether they communicate with each other with respect to their risk of being attacked by insect herbivores has been more controversial. We have found that sagebrush plants that are attacked by insects or mechanically damaged emit volatiles. Neighboring sagebrush plants sense these volatiles and increase their resistance to herbivory. Volatiles are required for this eavesdropping between individuals and between branches on a single individual. In the field, this eavesdropping increased the survival of seedlings and the production of flowers and new shoots for older plants. Individual plants showed relatively stable tendencies in their emission of active cues and also in their responses to cues. In other words, they showed tendencies that were consistent over time and also consistent across different situations, i.e., they exhibited personalities. For example, individuals that were good receivers were also good emitters. Recognizing that plants communicate via volatile cues expands our view of the sophisticated behaviors that plants are capable of. It may also allow us to design more effective pest management strategies. Recognizing that plants have individual personalities forces us to think about their past experiences and to consider correlations between behaviors.

Zoom link for those unable to attend in person:
https://ucla.zoom.us/j/94308730584?pwd=[REDACTED]
Meeting ID: 943 0873 0584
Passcode: [REDACTED]

Bret Beheim, MPI-EVAN - "Planck's Principle, Price's Theorem and the Forces of Cultural Evolution" (via Zoom)
2025-11-17 12:00 - 13:30
Abstract:
Physicist Max Planck famously said that “A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die”. This is basically a theory of human cultural change, one rooted primarily in the mechanisms of differential recruitment, inheritance and demography. If the Planck Principle (as it has come to be known) is a key explanatory force, it has major implications for the study of cultural evolution, which has instead traditionally focused on the role of social and individual learning (as people ‘see the light’). Although there have been several projects focusing on the role of demographic turnover in cultural evolution, evidence to date has been mixed and equivocal. A key theoretical limitation has been the lack of a principled way to compare the relative strength of different forces of cultural evolution.
To solve this problem, we adapt the method of *evolutionary decomposition* pioneered in mathematical demography, which applies Price’s Theorem to trajectories of phenotypic change. Using a novel derivation of this approach tailored to historical archives of creative human culture, we can measure (for the first time) the relatively explanatory strength of three categories of force in cultural evolution, namely, the entrances of new cohorts, the process of attrition, and the “changiness” of individuals over the course of their creative careers. Taking this to a variety of high-resolution longitudinal datasets, including song lyrics, board game strategies, and stylistic themes in European literature and musical compositions, we find strong evidence for the importance of population turnover and the entrance of new cohorts with splashy, disruptive ideas. Rather than Planck’s formulation of cultural change “one funeral at a time”, however, we find instead many circumstances where cultural change occurs “one birth at a time”. We also find systematic differences in the relative strength of these three categories of force, with some systems being driven by social learning and strategic adoption dynamics consistent with the canonical models of social learning, while others being mostly characterized by the slower process of demographic replacement. Our results demonstrate the value of an expanded, force-centric approach to studying long-term cultural change.
Zoom link:
https://ucla.zoom.us/j/94308730584?pwd=[REDACTED]
Meeting ID: 943 0873 0584
Passcode: [REDACTED]

Katie Sayres, UCSB - Title: "Loneliness and health: insights from the Tsimane Health and Life History Project"
2025-12-01 12:00 - 13:30
Abstract: Loneliness as a public health concern has exploded in recent years. Recognition of its widespread prevalence and presumed recency have led to declarations that a “loneliness epidemic” faces industrialized populations. Changes to certain aspects of modern life—fewer face-to-face interactions, more time spent alone, more people living by themselves—are thought to exacerbate loneliness, and imply that it may be a relatively recent phenomenon, tied to capitalism and the market economy. Recent meta-analyses, however, suggest that adults in lower- and middle-income countries also experience loneliness, despite living in socially embedded contexts. Still, most research on loneliness and its behavioral and health correlates focuses primarily on those people living in higher-income countries. In this talk, I will discuss recent work examining loneliness, the social environment, and health in Tsimane and Moseten forager-horticulturalists of Bolivia. This work challenges the concept that loneliness necessarily results from processes of the market economy, and suggests that loneliness is not confined to industrialized settings but likely represents a shared aspect of human experience.
Zoom link for those unable to attend in person:
https://ucla.zoom.us/j/94308730584?pwd=[REDACTED]
Meeting ID: 943 0873 0584
Passcode: [REDACTED]
