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These software and programs afford the user greater control and flexibility in tailoring complex hierarchical models. However, this level of control and flexibility places a higher degree of responsibility on the user to evaluate the robustness of their statistical inference. To determine how often biologists are running model diagnostics on hierarchical models, we reviewed 50 recently published papers in 2021 in the journalNature Ecology & Evolution, and we found that the majority of published papers didnotreport any validation of their hierarchical models, making it difficult for the reader to assess the robustness of their inference. This lack of reporting likely stems from a lack of standardized guidance for best practices and standard methods.

Here, we provide a guide to understanding and validating complex models using data simulations. To determine how often biologists use data simulation techniques, we also reviewed 50 recently published papers in 2021 in the journalMethods Ecology & Evolution. We found that 78% of the papers that proposed a new estimation technique, package or model used simulations or generated data in some capacity (18 of 23 papers); but very few of those papers (5 of 23 papers) included either a demonstration that the code could recover realistic estimates for a dataset with known parameters or a demonstration of the statistical properties of the approach. To distil the variety of simulations techniques and their uses, we provide a taxonomy of simulation studies based on the intended inference. We also encourage authors to include a basic validation study whenever novel statistical models are used, which in general, is easy to implement.

Simulating data helps a researcher gain a deeper understanding of the models and their assumptions and establish the reliability of their estimation approaches. Wider adoption of data simulations by biologists can improve statistical inference, reliability and open science practices.

A total of 106 agroforests across a 30,000‐km²landscape were surveyed for amphibians using a combination of visual and auditory encounter surveys. We used a Bayesian multi‐species occupancy modelling framework to examine patterns of species richness, beta diversity, dominance structure and individual species occupancies. The influence of biogeographic variables such as elevation and latitude as well as microhabitat availability of streams, ponds and unpaved plantation roads was tested on amphibian species occupancy.

Coffee agroforests had the highest species richness and lowest dominance when compared to areca and rubber. Beta diversity was highest in areca for within agroforest measures. Compared across agroforests, coffee had highest beta diversity with areca and rubber. Both elevation and latitude showed an overall positive association with amphibian occupancy, although species‐specific responses varied considerably.

Microhabitat availability was one of the strongest predictors of amphibian occupancy, with mean community response being positive with presence of water bodies and roads. Pond presence increased species richness per site by 34.7% (species‐specific responses in occupancy ranged from –2.7% to 327%). Stream presence alone did not change species richness but species‐specific response ranged from –59% to 273%. Presence of plantation roads also increased species richness by 21.5% (species‐specific response ranged from –82% to 656%). Being unpaved with little vehicular traffic, plantation roads seem to provide additional habitats for amphibians. Presence of all three microhabitats at a site increased species richness by 75%.

Our study highlights the importance of land management strategies that maintain diverse native canopy and freshwater bodies and other microhabitats in sustaining amphibian fauna. Market‐driven land‐use change from coffee to other agroforest types will have detrimental effects on amphibian communities and their long‐term sustainability in the Western Ghats.

We review recent literature on reptile demographic senescence, mechanisms of senescence, and identify unanswered questions. Given the ecophysiological and demographic diversity of reptiles, what is the expected range of reptile senescence rates? Are known mechanisms of ageing in reptiles consistent with canonical hallmarks of ageing in model systems? What are the knowledge gaps in our understanding of reptile ageing?

We find ample evidence of increasing mortality with advancing age in many reptiles. Testudines stand out as slower ageing than other orders, but data on crocodilians and tuatara are sparse. Sex‐specific analyses are generally not available. Studies of female reproduction suggest that reptiles are less likely to have reproductive decline with advancing age than mammals.

Reptiles share many physiological and molecular pathways of ageing with mammals, birds and laboratory model organisms. Adaptations related to stress physiology coupled with reptilian ectothermy suggest novel comparisons and contrasts that can be made with canonical ageing phenotypes in mammals. These include stem cell and regeneration biology, homeostatic mechanisms, IIS/TOR signalling, and DNA repair.

To overcome challenges to the study of reptile ageing, we recommend extending and expanding long‐term monitoring of reptile populations, developing reptile cell lines to aid cellular biology, conducting more comparative studies of reptile morphology and physiology sampled along relevant life‐history axes and sequencing more reptile genomes for comparative genomics. Given the diversity of reptile life histories and adaptations, achieving these directives will likely greatly benefit all ageing biology.