Biology subjects

Ramos-Fernandez, G.

Publications and source records attributed to Ramos-Fernandez, G..

5 recordsLinked to original sources

bioRxiv2025

Social integration in temporal multiplex association networks predicts offspring survival in female Geoffroy's spider monkeys (Ateles geoffroyi)

While sociality is considered an important factor influencing female reproductive success, it is unclear how temporal social dynamics relate to it. We address this by evaluating the influence of social integration and its stability over time on offspring production and survival in Geoffroys spider monkeys (Ateles geoffroyi). Using 52,670 subgroup scan samples collected between 1997 and 2020, we compiled yearly association matrices among the sexually mature individuals of a wild group of spider monkeys, based on spatio-temporal co-occurrence in subgroups. We built Bayesian edge-weight models with the association matrices and generated 1000 samples of each yearly network, which we then used as layers in temporal multiplex networks. For each female with adult tenure [≥] 5 years (n= 17), we estimated strength and eigenvector versatility in the multiplex network that comprised the last 5 years of her tenure. We also estimated six (monolayer) centrality-based metrics in the yearly networks of females with adult-tenure [≥] 1 year and at least one recorded offspring born in the group (n=22). We tested the influence of these eight indicators of social integration as predictors of offspring production and survival. Results showed overall positive relationships between social integration and offspring survival, but not offspring production. The former could be due to better access to food resources or protection from within-group aggression. Our temporal multilayer approach contributed to the body of evidence regarding the fitness benefits of sociality. Significance StatementDespite the growing evidence of the influence of sociality on female fitness, there is limited information on how temporal variation in social dynamics relates to female reproductive success. We used long-term data on spatio-temporal co-occurrence in subgroups of spider monkeys to estimate network centrality metrics. We found that females with higher and more stable social integration had higher offspring survival, particularly for female offspring who reached age 5 (the onset of sexual maturity). Our study offers insights into the relationship between association and offspring survival in species with a high degree of fission-fusion dynamics and female dispersal.

animal behavior and cognition↗

bioRxiv2023

Collective pooling of foraging information in animal fission-fusion dynamics

1In animal species with fission-fusion dynamics, individuals can split from or follow others during collective movements. In spider monkeys (Ateles geoffroyi) this decision depends in part on the information they have about the location of available feeding trees. Foraging widely and continuously splitting and joining from others, individuals could be pooling their partial information such that the group as a whole has a more complete picture of a heterogeneous foraging environment. Here we use individual utilization areas over a realistic foraging landscape to infer the sets of potentially known trees by each individual. Then we measure the spatial entropy of these areas, considering tree species diversity and spatial distribution. We measure how complementary pairs of areas are, by decomposing the spatial entropy into redundant and unique components. We find that the areas uniquely known by each pair member still contain considerable amounts of information, but there is also a high redundancy in the information that a pair has about the foraging landscape. The networks joining individuals based on the unique information components seem to be structured efficiently for information transmission. Distributed foraging in fission-fusion dynamics would be an example of adaptive pooling of information and thus, collective intelligence.

animal behavior and cognition↗

bioRxiv2023

Levy movements and a slowly decaying memory allow efficient collective learning in groups of interacting foragers

Many animal species benefit from spatial learning to adapt their foraging movements to the distribution of resources. Learning involves the collection, storage and retrieval of information, and depends on both the random search strategies employed and the memory capacities of the individual. For animals living in social groups, spatial learning can be further enhanced by information transfer among group members. However, how individual behavior affects the emergence of collective states of learning is still poorly understood. Here, with the help of a spatially explicit agent-based model where individuals transfer information to their peers, we analyze the effects on the use of resources of varying memory capacities in combination with different exploration strategies, such as ordinary random walks and Levy flights. We find that individual Levy displacements associated with a slow memory decay lead to a very rapid collective response, a high group cohesion and to an optimal exploitation of the best resource patches in static but complex environments, even when the interaction rate among individuals is low. Author SummaryHow groups of social animals collectively learn to find and exploit resources in complex environments is not well-understood. By means of a computational model where individuals are initially spread out across a landscape, we study the effects of individual exploratory behaviors and memory capacities on the emergence of spatial learning. Collective learning emerges spontaneously only if group members transfer information between each other at a sufficiently high rate, so that individual experiences can be used by others. In static but heterogeneous environments with many resource sites of varying attractiveness, we find that random displacements over many spatial scales combined with a slow memory decay lead to a rapid collective response and highly cohesive groups. Collective learning is noticeable through an optimal exploitation of the best resource sites, which far exceeds what individuals would achieve on their own. Our study sheds light on important mechanisms responsible for collective learning in ecology, with potential applications in other areas of science.

animal behavior and cognition↗

bioRxiv2022

Flexible use of contact calls in a species with high fission-fusion dynamics

The social complexity hypothesis posits that complex social systems (that entail high uncertainty) require complex communicative systems (with high vocal flexibility). In species with fission-fusion dynamics, where the fluid composition of temporary subgroups increases the uncertainty with which group members must manage their social relationships, vocal communication must be particularly flexible. This study assessed whether contact call rates vary with caller and audience characteristics in free-living spider monkeys, as well as with fission and fusion events. Adult females and immature individuals called more when in small audience settings, while audience size did not influence adult males. Adults called more when in the presence of the opposite sex, whereas immatures vocalized more in subgroups composed only by females. Females also called more when with their mature sons. We found higher call rates in periods during which fission and fusion events took place than in periods with more stable compositions and when the composition after a fission or fusion event changed from one sex to two sexes. A flexible use of contact calls allows individuals to identify themselves when they join others, particularly if they are members of the opposite sex. This socio-spatial cohesion function reduces the uncertainty about subgroup composition.

animal behavior and cognition↗

bioRxiv2020

Multiple resource use strategies confer resilience to the socio-ecosystem in a protected area in the Yucatan Peninsula, Mexico

Natural Protected Areas (NPAs) are the main biodiversity conservation strategy in Mexico. Generally, NPAs are established on the territories of indigenous and rural groups driving important changes in their local resource management practices. In this paper we study the case of Otoch Maax Yetel Kooh, an NPA in the Yucatan Peninsula, Mexico, that has been studied in a multidisciplinary way for more than twenty years. This reserve and its buffer zone is homeland to Yucatec Mayan communities that until recently used to manage their resources following a multiple use strategy (MUS), which involves local agricultural practices and has been proposed as resilience-enhancing mechanism. However, due to the restrictions imposed by the decree of the reserve and the growth of tourism in the region, some of these communities have started to abandon the MUS and specialize on tourism-related activities. We build a dynamical computational model to explore the effects of some of these changes on the capacity of this NPA to conserve the biodiversity and on the resilience of households to some frequent disturbances in the region. The model, through the incorporation of agent-based and boolean network modelling, explores the interaction between the forest, the monkey population and some productive activities done by the households (milpa agriculture, ecotourism, agriculture, charcoal production). We calibrated the model, explored its sensibility, compared it with empirical data and simulated different management scenarios. Our results suggest that those management strategies that do not exclude traditional activities may be compatible with conservation objectives, supporting previous studies. Also, our results support the hypothesis that the MUS, throughout a balanced integration of traditional and alternative activities, is a mechanism to enhance household resilience in terms of income and food availability, as it reduces variability and increases the resistance to some disturbances. Our study, in addition to highlighting the importance of local management practices for resilience, also illustrates how computational modeling and systems perspective are effective means of integrating and synthesizing information from different sources.

ecology↗