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1. Maternal effect senescence and caloric restriction interact to affect fitness through changes in life history timing

   https://doi.org/10.1111/1365-2656.14220  

   Hernández, Christina M; van_Daalen, Silke F; Liguori, Alyssa; Neubert, Michael G; Caswell, Hal; Gribble, Kristin E (January 2025, Journal of Animal Ecology)

   Abstract Environmental factors and individual attributes, and their interactions, impact survival, growth and reproduction of an individual throughout its life. In the clonal rotiferBrachionus, low food conditions delay reproduction and extend lifespan. This species also exhibits maternal effect senescence; the offspring of older mothers have lower survival and reproductive output. In this paper, we explored the population consequences of the individual‐level interaction of maternal age and low food availability.We built matrix population models for both ad libitum and low food treatments, in which individuals are classified both by their age and maternal age. Low food conditions reduced population growth rate () and shifted the population structure to older maternal ages, but did not detectably impact individual lifetime reproductive output.We analysed hypothetical scenarios in which reduced fertility or survival led to approximately stationary populations that maintained the shape of the difference in demographic rates between the ad libitum and low food treatments. When fertility was reduced, the populations were more evenly distributed across ages and maternal ages, while the lower‐survival models showed an increased concentration of individuals in the youngest ages and maternal ages.Using life table response experiment analyses, we compared populations grown under ad libitum and low food conditions in scenarios representing laboratory conditions, reduced fertility and reduced survival. In the laboratory scenario, the reduction in population growth rate under low food conditions is primarily due to decreased fertility in early life. In the lower‐fertility scenario, contributions from differences in fertility and survival are more similar, and show trade‐offs across both ages and maternal ages. In the lower‐survival scenario, the contributions from decreased fertility in early life again dominate the difference in .These results demonstrate that processes that potentially benefit individuals (e.g. lifespan extension) may actually reduce fitness and population growth because of links with other demographic changes (e.g. delayed reproduction). Because the interactions of maternal age and low food availability depend on the population structure, the fitness consequences of an environmental change can only be fully understood through analysis that takes into account the entire life cycle. 

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2. Optimal bounds for ancient caloric functions

   https://doi.org/10.1215/00127094-2021-0015  

   Colding, Tobias Holck; Minicozzi II, William P. (December 2021, Duke Mathematical Journal)
3. BMO Solvability and Absolute Continuity of Caloric Measure

   https://doi.org/10.1007/s11118-020-09833-9  

   Genschaw, Alyssa; Hofmann, Steve (March 2021, Potential Analysis)

   null (Ed.)
4. A Weak Reverse Hölder Inequality for Caloric Measure

   https://doi.org/10.1007/s12220-019-00212-4  

   Genschaw, Alyssa; Hofmann, Steve (April 2020, The Journal of Geometric Analysis)
5. Divergent impacts of crop diversity on caloric and economic yield stability

   https://doi.org/10.1088/1748-9326/aca2be  

   Driscoll, Avery W.; Leuthold, Sam J.; Choi, Eunkyoung; Clark, Samantha M.; Cleveland, Daniel M.; Dixon, Mary; Hsieh, Marian; Sitterson, Jan; Mueller, Nathaniel D. (November 2022, Environmental Research Letters)

   Abstract Food security and the agricultural economy are both dependent on the temporal stability of crop yields. To this end, increasing crop diversity has been suggested as a means to stabilize agricultural yields amidst an ongoing decrease in cropping system diversity across the world. Although diversity confers stability in many natural ecosystems, in agricultural systems the relationship between crop diversity and yield stability is not yet well resolved across spatial scales. Here, we leveraged crop area, production, and price data from 1981 to 2020 to assess the relationship between crop diversity and the stability of both economic and caloric yields at the state level within the USA. We found that, after controlling for climatic instability and differences in irrigated area, crop diversity was positively associated with economic yield stability but negatively associated with caloric yield stability. Further, we found that crops with a propensity for increasing economic yield stability but reducing caloric yield stability were often found in the most diverse states. We propose that price responses to changes in production for high-value crops underly the positive relationship between diversity and economic yield stability. In contrast, spatial concentration of calorie-dense crops in low-diversity states contributes to the negative relationship between diversity and caloric yield stability. Our results suggest that the relationship between crop diversity and yield stability is not universal, but instead dependent on the spatial scale in question and the stability metric of interest. 

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