Arani, B. M. S. | Search bioRxiv

bioRxiv2024

Improved potential analysis for inadequate ecological data

Potential analysis is used in many ecological studies to infer whether or not an ecosystem can have alternative stable states, to estimate the tipping points and, to assess the resilience of ecosystems. The main reason behind its frequent use is that such a frequency-based analysis is a minimalistic modelling strategy and therefore, is well-suited for limited ecological data with measurement errors. It has been used extensively in tree cover studies to discern alternative states of savannah and forest, the regime upon which savannah and forest coexist and, their corresponding resilience. Classical potential analysis may produce biased results due to inherent theoretical and practical limitations. This letter introduces a more sophisticated approach to address these shortcomings and enhance predictive capabilities regarding ecological dynamics, especially when working with insufficient data whose incorrect analysis can significantly impact management strategies.

ecology↗

bioRxiv2021

Eusociality and the evolution of aging in superorganisms

Eusocial insects - ants, bees, wasps and termites - are being recognized as model organisms to unravel the evolutionary paradox of aging for two reasons: (1) queens (and kings, in termites) of social insects outlive similar sized solitary insects by up to several orders of magnitude; (2) all eusocial taxa show a divergence of long queen and shorter worker lifespans, despite their shared genomes and even under risk-free laboratory environments. Traditionally, these observations have been explained by invoking classical evolutionary aging theory: well-protected inside their nests, queens are much less exposed to external hazards than foraging workers, and this provides natural selection the opportunity to favor queens that perform well at advanced ages. Although quite plausible, these verbal arguments have not been backed up by mathematical analysis. Here, for the first time, we provide quantitative models for the evolution of caste-specific aging patterns. We show that caste-specific mortality risks are in general neither sufficient nor necessary to explain the evolutionary divergence in lifespan between queens and workers and the extraordinary queen lifespans. Reproductive monopolization and the delayed production of sexual offspring in highly social colonies lead natural selection to inherently favor queens that live much longer than workers, even when exposed to the same external hazards. Factors that reduce a colonys reproductive skew, such as polygyny and worker reproduction, tend to reduce the evolutionary divergence in lifespan between queens and workers. Caste-specific extrinsic hazards also affect lifespan divergence but to a much smaller extent than reproductive monopolization.

evolutionary biology↗