Biology subjects

Garber, P. A.

Publications and source records attributed to Garber, P. A..

3 recordsLinked to original sources

bioRxiv2026

A data-driven redefinition of global biodiversity hotspots

The 36 global biodiversity hotspots harbor a disproportionate share of the worlds endemic species, making their conservation critical for planetary health. Traditionally hotspots were defined as ecoregions with [≥]1,500 endemic vascular plant species and >70% natural habitat loss; this relied heavily on expert judgment, with subjective assessments of endemism and habitat loss applied. Challenges in defining endemism, quantifying habitat loss, and the global unevenness in available vascular plant data have hindered hotspot identification over the past decades. Here, we built a global dataset of 150,487 rare vascular plants, identified from 88.1% of the worlds known vascular species, and recognize hotspots based on their richness using three complementary conservation targets and algorithms. We then quantified natural habitat loss and habitat fragmentation using high-resolution remote sensing data and assessed the diversity and distribution of terrestrial vertebrates within these newly identified hotspots. Our data-driven method recovered all the 36 established global biodiversity hotspots, revised 17, and identified 11 new hotspots spanning diverse ecosystems across six continents. These 47 hotspots cover 26.63% of global land area, yet contain 83.8% of rare vascular plants, 92.4% of mammals, 96.1% of birds, 87.8% of reptiles, and 95.0% of amphibians. Collectively, they encompass >89% of terrestrial vertebrates classified as IUCN threatened species. Only 10 hotspots have undergone [≥]70% habitat loss, and the lack of a consistent relationship with habitat fragmentation suggests that this criterion is not globally applicable. Effectively protecting [~]27% of Earths land could theoretically safeguard >89.8% of threatened terrestrial species and >67% of threatened terrestrial species hotspot area, assuming effective protection of the identified biodiversity hotspots. Targeted conservation efforts within these global biodiversity hotspots can meet the established biodiversity targets of the Kunming-Montreal Global Biodiversity Framework as well as post-2030 biodiversity targets. Most importantly, our framework enables conservation scientists to iteratively identify and update global biodiversity hotspots in step with growing global biodiversity data.

ecology↗

bioRxiv2026

Allonursing (Co-BreeD): Its prevalence, functions and hypotheses across mammals and human cultures

Allonursing, where dependent young are nursed by females other than their mothers, has been observed across diverse mammalian species and human cultures. Yet, the proximate functions underlying this seemingly altruistic behaviour, and its benefits for the offspring, the mother, and the nursing allomother, remain poorly understood. To facilitate testing hypotheses concerning these questions, we compiled the to date largest allonursing dataset from wild populations (N = 101 species, including 133 populations and 5 human cultures). Using this dataset, we (i) map the taxonomic distribution of allonursing, thereby expanding the list of mammal species qualified as cooperative breeders by 17 additional species, (ii) differentiate cases of non-voluntary from voluntary allonursing and consequently reject the hypothesis that milk stealing explains regular allonursing in most species, (iii) quantify the within-population extent of allonursing to assess its significance across species and evaluate the energy/time saved for mothers, (iv) use phylogenetically controlled analyses to revisit the association between allonursing and polytocy (i.e., litter size >1), and provide an alternative explanation for this association. We conclude by proposing that allonursing has multiple functions, with the most empirically supported ones being provisioning and insurance against maternal loss. Finally, the presented AlloNursing dataset complements the Cooperative-Breeding Database (Co-BreeD) to further expand this integrative resource for cooperative breeding research.

animal behavior and cognition↗

bioRxiv2025

Diet, Climatic Conditions, and Sex Affect the Mycobiome of Wild Common Marmosets (Callithrix jacchus)

Recent research on the gut mycobiome, or the fungal portion of the gut microbial community, suggests that it interacts with host physiology and impacts host health. However, fundamental questions about how the mycobiome is assembled remain unanswered. It remains unclear whether the fungi detected in the gut are predominantly residents of the gastrointestinal tract or if they are largely transient and pass through. To address this question, we sought to determine whether host factors (e.g., sex) or external environmental factors (e.g., variable climatic conditions and diet) were more strongly correlated with the gut mycobiome of common marmosets (Callithrix jacchus), a primate species living in the semi-arid Caatinga biome of northeastern Brazil. A stronger correlation with host factors, would suggest a more resident mycobiome, while a stronger association with external environmental factors suggests a more transient mycobiome. We collected 52 marmoset fecal samples across a 2-year period and DNA metabarcoding was used to assess both the mycobiome and diet of each sample. We used FUNGuild to assign ecological roles to the fungi, which were sorted into resident (e.g. animal pathogens) and transient (e.g. plant pathogens) groups. We found that mycobiome richness and evenness varied by host sex and correlated with the arthropod component of the diet while mycobiome composition varied between wetter and drier periods and correlated with the plant portion of the diet. The fact that external environmental factors were associated with the presence of specific taxa led us to conclude that the mycobiome is largely made up of transient taxa. ImportanceOther than causing infectious diseases, the function of the mycobiome is poorly understood. There is evidence that the mycobiome can play a positive role, such as training the hosts immune system, and a negative role, such as causing cancer and Alzheimers disease. To fully understand these associations, basic questions about which taxa live in the host and which pass through, must be addressed. We used DNA metabarcoding and a tool that can group fungi based on their ecological roles, to determine whether the mycobiome of Caatinga marmosets was more strongly correlated with host sex or host diet and environment. We found that the marmoset mycobiome was more strongly correlated with diet and environment and most fungi passed through the host rather than lived in the hosts gut.

microbiology↗