A note on discretising Keyfitz entropy

In this short paper with Roberto Salguero-Gómez and Connor Bernard we show that a commonly used discrete-time formula for Keyfitz entropy does not preserve the simple relationship with increasing, decreasing, and constant mortality that the continuous-time formula had. We propose a new discrete-time formula instead, and show that the proposed new metric correctly classifies increasing, decreasing, and constant mortality survivorship curves. We also show that the previously used metric is particularly bad at classifying species with low life expectancies leading to a spurious correlation between the shape and the pace of life when this metric is used.

Two new preprints!

Two new preprints out in the world! The first is a collaboration with Hanna Kokko and Matthias Galipaud about Williams hypothesis, answering the question “Do environments or species traits that lower the mortality of individuals create selection for delaying senescence?”: The second is a collaboration with Colin Olito, where we investigate the demographic costs of sexually antagonistic alleles in partially selfing populations:


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Another preprint bites the dust!

As the title promises: another preprint bites the dust! By which I mean: another preprint online, obviously. This one was led by Petteri Karisto and in it we show how positive fitness effects can explain the broad range of Wolbachia prevalences found in nature together with Anne Duplouy and Hanna Kokko:

And in other news, the final peer reviewed version of the demographic costs of selfing paper with Colin Olito is out on the AmNat website with a new and improved Figure 1 that we hope you will love as much as we love it:

Demography when history matters

Interested in how to incorporate prior state dependence in a demographic model? Here’s a blog post on demography when history matters, summarising our paper on this (with Hal Caswell).


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