# Extinction of undiscovered butterflies

Meryl Theng just had a new paper published in Biological Conservation, where she estimated that 46% of Singapore’s butterfly species have been extirpated since 1854. The special thing about this estimate is that it includes all species that existed, including species that went extinct before we had a chance to discover them. The trick to estimating undiscovered extinctions is the SEUX model. There is a … Continue reading Extinction of undiscovered butterflies

# New solutions for Parker sperm competition model

Parker et al. (2013) created a general model for sperm allocation under a trade-off between male investment of resources $$R$$ into pre-copulatory effort (e.g. search time) $$T$$ versus post-copulatory effort (e.g. ejaculate) $$U$$. Their model is interesting because it encompasses a range of different scenarios of female remating and the type of competition between males. For female remating scenarios, the risk model has females mating … Continue reading New solutions for Parker sperm competition model

# Playing with a new model for fugitive coexistence

I recently read a paper by Kawecki (2017), which presents a new mechanism for something analogous to fugitive coexistence. The paper has a really great literature overview, which I won’t be able to do justice here. In short, fugitive coexistence is when an inferior species persists on a patchy landscape by being a better coloniser: when a local extinction occurs, they are quicker to arrive … Continue reading Playing with a new model for fugitive coexistence

# Typo in qualitative modelling paper

There is a typo in our recent paper to MEE, Dealing with high uncertainty in qualitative network models using Boolean analysis. Example 2 of Box 1 should read “y = water/wine” not “y = wine/water”. Many thanks to Anubhav Gupta at University of Zurich for emailing us to let us know. Continue reading Typo in qualitative modelling paper

# Pretty diagram of directory structure

In a recent project, I wanted to create a diagram of a repository for the appendix of a paper, including comments to highlight key files and explain how the folders were organised. I found this answer on Stack Exchange by user Gonzalo Medina, which I tweaked to produce the diagram below. The code is below: Continue reading Pretty diagram of directory structure

# Why does it matter to conservation decision-making if alternative Qualitative Modelling methods produce contradictory predictions?

Previously, I have written about how the probabilistic approach to Qualitative Modelling (QM) (e.g. Raymond et al. 2011) can lead to contradictory predictions of species response to a management intervention, and how this is similar to the paradoxes of the Principle of Indifference that we find in the philosophy literature. A reviewer of our new manuscript (Kristensen et al. 2019) asked us an interesting and … Continue reading Why does it matter to conservation decision-making if alternative Qualitative Modelling methods produce contradictory predictions?

# Fixation probability of birth-death process

The goal is to understand where Eq. 2 of the Supplementary section of Sigmund et al. (2010) came from. We are considering a finite population within which individuals are pursuing different game-theoretic strategies. At each timestep, a pair of individuals is chosen at random, and they engage in a social learning process, where individual $$i$$ will adopt the strategy of individual $$j$$ according … Continue reading Fixation probability of birth-death process

# Two new papers about blue tits on Corsica

I recently read two new papers about blue tits in Corsica: Dubuc-Messier et al. (2017 Behav. Ecol.), and Dubuc-Messier et al. (2018 Evol. Biol.). The 2018 paper was interested in whether the differences between the evergreen and deciduous ecotypes on Corsica were genetic or a plastic response to the different habitat types. They took 7-12 day old nestlings and raised them in a common garden, … Continue reading Two new papers about blue tits on Corsica

# Moments for a bivariate beta distribution

A common choice for a probability distribution of a probability is the beta distribution. It has the required support between 0 and 1, and with its two parameters we can obtain a pretty wide qualitative range for the probability density function. What should we do if we want to create correlated probabilities? We might look for some kind of multivariate generalisation of the beta distribution, … Continue reading Moments for a bivariate beta distribution