Anthropogenic habitat modification can reshape dispersal dynamics, social organisation, and ultimately the genetic structure of populations. In cooperatively breeding species, where philopatry and helping are common, dispersal events are rare but critical for maintaining gene flow and reducing inbreeding. Using microsatellite data (N = 211 individuals) and long-term (1985 - 2023) social kinship data from the cooperatively breeding Arabian babblers (Argya squamiceps) living in natural and modified habitats in the hyper-arid Arava Valley (Israel), we examined how habitat modification influences the social and genetic structure. We combined spatial autocorrelation analyses, within-group relatedness estimates, and social kinship to assess patterns of dispersal, connectivity, and kinship across habitats. We found high gene flow across habitats and only weak differentiation among subpopulations, consistent with recent habitat changes that do not produce strong divergence. However, subtle but significant differences emerged between natural and modified habitats. Groups inhabiting modified areas showed shorter dispersal distances and lower within-group relatedness, suggesting higher turnover and increased immigration of unrelated individuals. In contrast, groups in natural habitats maintained stronger kin-based cohesion and broader positive spatial genetic structure. Our results indicate that habitat modification does not reduce connectivity in this system but reshapes the balance between philopatry and dispersal, favouring earlier dispersal and reduced kinship within groups. Modified habitats attract and concentrate individuals from multiple origins, while natural habitats function as demographic sources. These findings corroborate previous behavioural evidence of an accelerated pace of life in modified habitats and demonstrate that such life-history adjustments are detectable in the genetic and social structure. More broadly, our study highlights how anthropogenic changes in arid ecosystems can leave rapid genetic signatures in cooperative breeders, underscoring the importance of integrating behavioural, demographic, and genetic perspectives to understand population responses to environmental change.

Habitat modification and climate change are major threats to biodiversity. Using 38 years of data (1985–2023), we examined their combined impact on a desert-dwelling cooperative breeder’s fitness and projected future fitness under two climate scenarios for the end of the century (2100). Rainfall increased reproductive success, while extreme temperatures reduced survival in natural habitats. Human-modified habitats buffered against climate extremes, resulting in higher fitness even in harsh years. Future projections indicate severe population declines in natural habitats, while modified habitats may offer climatic refugia. Larger social groups enhanced resilience, highlighting the importance of helpers in cooperatively breeding species. However, even large group size might not alleviate future extreme climate conditions. Our findings highlight the need to assess multiple anthropogenic stressors together to fully understand their impact on species’ fitness and the importance of long-term projects in addressing the complex relationship between them.

Anthropogenic habitat modification is especially detrimental to social species. Apart from direct fitness effects, it can destroy group structure and affect social interactions crucial for reproduction and survival. Here, we assessed the impact of habitat modification on the fitness and life history traits of a cooperative breeder, the Arabian babbler (Argya squamiceps). We collected spatial, reproductive, and social data on 572 individuals belonging to 21 social groups over six years and combined it with remote sensing to characterize group territories. Groups in modified habitats bred more and had greater productivity during dry years. Males living in modified habitats dispersed and acquired dominance at a younger age, showing a faster pace of life. However, group performance and total fitness were higher in natural habitats during average years. Habitat modification indirectly affected fitness by altering social structure, whereby younger males who lacked experience became dominant, leading to reduced nesting success.