How Many First-Authored Papers in "Leading" Journals Does One Need to be Hired as an Assistant Professor?

This is in ecology, but we can think of analogous exercises for mathematics and physics (including also with numbers of citations of papers at the time of being hired).

How many first-authored papers in “leading” journals does an ecologist need to be hired as a tenure-track asst. prof at an R1 university? Not nearly as many as most ecologists think. https://t.co/qpfozljVD0 pic.twitter.com/VrcfEbTjdh

— Dynamic Ecology (@DynamicEcology) October 2, 2018

FYI: I have seen several things on this blog over the years that are relevant far beyond their core ecology audience, so it's worth a look beyond this post.

Update: It's also not required to have lots of citations to get a top faculty job. It would be good to see a distribution of what people have had in practice. (The number of citations listed by Google Scholar for me for 2006 is 53.)

"Inferring Parameters of Prey Switching in a 1 Predator–2 Prey Plankton System with a Linear Preference Tradeoff"

Another of my papers came out in final published form today.

Title: Inferring Parameters of Prey Switching in a 1 Predator–2 Prey Plankton System with a Linear Preference Tradeoff

Authors: Sofia H. Piltz, Lauri Harhanen, Mason A. Porter, and Philip K. Maini

Abstract: We construct two ordinary-differential-equation models of a predator feeding adaptively on two prey types, and we evaluate the models’ ability to fit data on freshwater plankton. We model the predator’s switch from one prey to the other in two different ways: (i) smooth switching using a hyperbolic tangent function; and (ii) by incorporating a parameter that changes abruptly across the switching boundary as a system variable that is coupled to the population dynamics. We conduct linear stability analyses, use approximate Bayesian computation (ABC) combined with a population Monte Carlo (PMC) method to fit model parameters, and compare model results quantitatively to data for ciliate predators and their two algal prey groups collected from Lake Constance on the German–Swiss–Austrian border. We show that the two models fit the data well when the smooth transition is steep, supporting the simplifying assumption of a discontinuous prey-switching behavior for this scenario. We thus conclude that prey switching is a possible mechanistic explanation for the observed ciliate–algae dynamics in Lake Constance in spring, but that these data cannot distinguish between the details of prey switching that are encoded in these different models.


Note: This paper is actually the third in a series of papers that arose from Sofia's doctoral thesis. In all three, we studied prey switching in plankton as a dynamical system. However, although we were concerned in all three papers with the same ecological situation, we modeled it in three different mathematical ways: using piecewise-smooth dynamical systems (in paper 1), using fast–slow dynamical systems (in paper 2), and using smooth dynamical systems (in this paper). It is really important to model the same phenomenon in different ways and to compare the qualitative features of the different models against each other as well as to empirical data. I am really pleased with this effort, which Sofia did a superb job of leading.

"Can Multilayer Networks Advance Animal Behavior Research?"

The final version of a new paper of mine now has its final coordinates in a journal. Here are some details.

Title: Can Multilayer Networks Advance Animal Behavior Research?

Authors: Matthew J. Silk, Kelly R. Finn, Mason A. Porter, and Noa Pinter-Wollman

Abstract: Interactions among individual animals — and between these individuals and their environment — yield complex, multifaceted systems. The development of multilayer network analysis offers a promising new approach for studying animal social behavior and its relation to eco-evolutionary dynamics.

"The Multilayer Nature of Ecological Networks"

Our perspective paper on multilayer networks in ecology is out in final form today! Here are the details.

Title: The Multilayer Nature of Ecological Networks

Authors: Shai Pilosof, Mason A. Porter, Mercedes Pascual, and Sonia Kéfi

Abstract: Although networks provide a powerful approach to study a large variety of ecological systems, their formulation does not typically account for multiple interaction types, interactions that vary in space and time, and interconnected systems such as networks of networks. The emergent field of ‘multilayer networks’ provides a natural framework for extending analyses of ecological systems to include such multiple layers of complexity, as it specifically allows one to differentiate and model 'intralayer' and 'interlayer' connectivity. The framework provides a set of concepts and tools that can be adapted and applied to ecology, facilitating research on high-dimensional, heterogeneous systems in nature. Here, we formally define ecological multilayer networks based on a review of previous, related approaches; illustrate their application and potential with analyses of existing data; and discuss limitations, challenges, and future applications. The integration of multilayer network theory into ecology offers largely untapped potential to investigate ecological complexity and provide new theoretical and empirical insights into the architecture and dynamics of ecological systems.

"A Predator–2 Prey Fast–Slow Dynamical System for Rapid Predator Evolution"

One of my papers has now been posted in final form. (A second one appeared online today, but it joins a long list of papers that are still awaiting their coordinates. I will blog about those papers when they have those coordinates.)

Anyway, let's talk about the paper that does have its coordinates. It's about plankton modeling, and here are the details.

Title: A Predator–2 Prey Fast–Slow Dynamical System for Rapid Predator Evolution

Authors: So a H. Piltz, Frits Veerman, Philip K. Maini, and Mason A. Porter

Abstract: We consider adaptive change of diet of a predator population that switches its feeding between two prey populations. We develop a novel 1 fast–3 slow dynamical system to describe the dynamics of the three populations amidst continuous but rapid evolution of the predator's diet choice. The two extremes at which the predator's diet is composed solely of one prey correspond to two branches of the three-branch critical manifold of the fast–slow system. By calculating the points at which there is a fast transition between these two feeding choices (i.e., branches of the critical manifold), we prove that the system has a two-parameter family of periodic orbits for su ciently large separation of the time scales between the evolutionary and ecological dynamics. Using numerical simulations, we show that these periodic orbits exist, and that their phase di erence and oscillation patterns persist, when ecological and evolutionary interactions occur on comparable time scales. Our model also exhibits periodic orbits that agree qualitatively with oscillation patterns observed in experimental studies of
the coupling between rapid evolution and ecological interactions.

What Happens in Göttingen Stays in Göttingen

I am now traveling to Göttingen for a workshop in ecology and "networks on networks". The program, which was sent to participants yesterday, makes it looks much more like a conference than a workshop.

Tales from the ArXiv: Herbivore Meltdown

I love the main label of the caption of Figure 5 (on page 12) of this new paper. It starts with the bold text "Meltdown of the herbivores." I love it!

Anyway, the next time you go into a forest, be very careful in case of herbivore meltdown. (I have all sorts of wonderful images in my head at the moment.)

And googling "herbivore meltdown" yields the fact that "ecological meltdown" is actually a standard term. It's certainly very image-provoking. I have to say, though, that I also find the term very humorous, even with its very serious implications.

Flipping the Test

A very cool test was given in a Behavioral Ecology class at UCLA. It sounds like it was a great learning experience for the students, and of course this story makes me think of a certain exam I once took in Philosophy of Probability. In both situations, the lessons from the course itself played center stage in the exam-taking strategy.

(Tip of the cap to Jasvir Grewal.)