Preprints
Filtering by Subject: Life Sciences
The Definition of Individual Biological Fitness
Published: 2024-10-08
Subjects: Life Sciences
Fitness is one of the central concepts in biology. Despite this, a precise definition of an individual's fitness remains elusive. Typically, 'biological fitness' is understood as the relative selective advantage of different genetic alleles. In this manuscript, we present a rigorous mathematical definition of individual fitness. This framework addresses an unjustifiable gap in evolutionary [...]
Coupled effects of forest growth and climate change on small mammal abundance and body weight: results of a 39-year field study
Published: 2024-10-08
Subjects: Life Sciences
1. In rapidly changing environments, the combined effects of climate change and forest stand changes—such as growth or regeneration—are altering the availability of resources, particularly in systems with pulsed resources like seed-masting. These environmental shifts can have cascading impacts on animal populations, ultimately reshaping ecosystem structure and function. However, relevant [...]
Rotten to the core? How internal stem damage varies vertically in savanna trees and is influenced by tree species, traits, and external damage pressures
Published: 2024-10-04
Subjects: Life Sciences
1. Trees are important aboveground carbon sinks in savanna ecosystems, yet consumption of internal wood by decomposers (e.g., termites and microbes) creates uncertainties in tree biomass accounting. It remains unclear whether internal stem damage is constant or variable throughout the tree, making it uncertain if a lower stem sample reflects damage in the entire tree. Furthermore, total damage [...]
How does climate change impact the population of polar bears? Environmental threats, ecological dynamics and conservation efforts
Published: 2024-10-04
Subjects: Life Sciences
Climate change is one of the major drivers of recent biodiversity loss on a global scale. Some species try to adapt to such changes through shifting their range and behaviour due to their habitat being altered or damaged. Within the Arctic regions, temperature rise is three times higher than the global average, affecting various species at different rates in this ecosystem. Such a warming effect [...]
Phenology-informed decline risk of estuarine fishes and their prey suggests potential for future trophic mismatches
Published: 2024-10-03
Subjects: Life Sciences
Conservation scientists have long used population viability analysis (PVA) on species count data to quantify trends and critical decline risk, thereby informing conservation actions. These assessments typically focus on single species rather than assemblages and assume that risk is consistent within a given life stage (e.g., across the different seasons or months of a year). However, if risk is [...]
European wild honeybee populations are endangered
Published: 2024-10-01
Subjects: Life Sciences
The population trends of wild western honeybees (Apis mellifera) have been neglected by conservationists because the species has been considered to consist of managed colonies only. New data suggest that wild honeybee colonies (still) make up one sixth to one fifth of the overall European honeybee population. The population trends of wild cohorts can be evaluated like those of any other native [...]
The best of both worlds: Why antipredator traits are lost in predator free havens and how to keep them
Published: 2024-10-01
Subjects: Life Sciences
As a response to the current biodiversity crisis, active management of threatened species has become more frequent, with predator-free havens an increasingly common conservation management strategy. In Australia, where introduced predators such as cats and foxes are one of the largest threats to native fauna, havens have played a key role in maintaining viable populations of endemic marsupials. [...]
A framework for reproductive outcomes of phenological match-mismatch in migratory breeders tested on a declining species, caribou
Published: 2024-10-01
Subjects: Life Sciences
Long distance migrants with endogenously timed reproduction may be especially vulnerable to phenological mismatch on summer ranges where offspring are produced and provisioned. This is because departure timing from winter ranges and breeding timing on summer ranges in such species is cued primarily by photoperiod while the timing of resource availability on summer ranges is cued by local [...]
Biology, genetics and ecology of the cosmopolitan ectomycorrhizal ascomycete Cenococcum geophilum
Published: 2024-09-30
Subjects: Life Sciences
The ascomycete Cenococcum geophilum is a cosmopolitan and ecologically significant ectomycorrhizal (ECM) fungus that forms symbiotic associations with diverse host plants globally across various ecosystems. As the only known ECM member of Dothideomycetes, C. geophilum exhibits several distinctive characteristics that distinguish it from other ECM fungi. Its high genetic diversity is particularly [...]
A historical confusion that has long permeated the sex paradox
Published: 2024-09-30
Subjects: Life Sciences
A historical misunderstanding permeates nearly every formulation of the sexual reproduction paradox, an age-old conundrum that continues to challenge the foundations of evolutionary theory. Recognizing this error will clarify the problem and facilitate its resolution.
Insect Lipid Metabolism in the Presence of Symbiotic and Pathogenic Viruses and Bacteria
Published: 2024-09-30
Subjects: Life Sciences
Insects, like most animals, have intimate interactions with microorganisms that can influence the insect host’s lipid metabolism. In this chapter, we describe what is known so far about the role prokaryotic microorganisms play in insect lipid metabolism. We start exploring microbe-insect lipid interactions focusing on endosymbionts, and more specifically the gut microbiota that has been [...]
Are Australia’s volcanic-forests “biogeographic continental islands”?
Published: 2024-09-30
Subjects: Life Sciences
This study investigates whether Cenozoic volcanic complexes in eastern Australia act as biogeographic islands, fostering high levels of terrestrial vascular plant endemism and range-restricted species compared to surrounding sedimentary landscapes. Over six million herbarium records were analysed to assess range-restriction using area of occupancy (AOO) and extent of occurrence (EOO). [...]
Temporal stability in songs across the breeding range of the Mourning Warbler may be due to learning fidelity and transmission biases
Published: 2024-09-30
Subjects: Animal Sciences, Behavior and Ethology, Ecology and Evolutionary Biology, Life Sciences, Ornithology
We found a stable pattern of geographic variation in songs across the breeding range of the Mourning Warbler over a 36 yr period. The Western, Eastern, Nova Scotia, and Newfoundland regiolects found in 2005-2009 also existed from 1983-1988 and 2017-2019. Each regiolect contained a pool of syllables that were unique and different from the other regiolects. The primary syllable types that defined [...]
Freshwater fish functional diversity shows diverse responses to human activities, but consistently declines in the tropics
Published: 2024-09-30
Subjects: Life Sciences
Freshwater environments are intertwined with human activities and the consequence has been environmental degradation and biodiversity loss. Fish provide key ecological and economic benefits, and fish abundance and diversity can be affected by human activities resulting in functional diversity (FD) changes that might scale up to ecosystem impacts. Changes in FD can be expressed by quantifying its [...]
Seedlings of Temperate Tree Species Show Plastic Responses to Water Deficit and Heat Stress, But They Do Not Prevent Decline in Growth
Published: 2024-09-30
Subjects: Life Sciences
Species response to climate change is difficult to predict because warming involves the interaction of multiple stressors whose effects are simultaneous and therefore difficult to disentangle. To address this gap, I studied the effect of global warming on plant performance and functional traits by exposing seedlings from five temperate tree species with distinct life histories to water deficit [...]