To facilitate discussions among members of the RCN, we have set up Slack channel at

To join the channel please visit this site. We encourage you to discuss the papers with other participants prior to joining the larger discussion on slack. For each topic, your group should choose one person to post a summary to the Slack channel that summarizes the group’s reaction to the papers and discussion questions. We have made efforts to improve representation and diversity in our selected readings. Please scroll to the bottom of this page for a diversity summary. Please contact René Clark if you encounter problems with Slack or accessing any of the readings.

To form a discussion group: 1) Start a group at your home institution and meet once or twice during each two-week period (any time during the two weeks is fine) to read and discuss the papers, 2) Discuss papers virtually before joining the larger discussion via the #2022-spring-readings group on the RCN Slack.

All participants can use the thread feature in Slack to post additional questions, and react to comments or questions posed by other groups. We will also have a weekly thread dedicated to resolving questions that emerge from the readings. Moderators will monitor threads and respond to questions. We encourage individuals or groups to use these threads to clarify any uncertainties.

Under Channels click the + and search for 2022-spring-readings

Each week will have two threads:

  • Under the thread Week X. <Topic Name> Post your group's discussions here, click on the chat icon Reply to thread to post a summary of your group’s discussions.
  • To ask a question about the papers, use the thread Week X. Questions for Understanding. If you have any technical questions about the papers, post them here and the moderators will do their best to answer them!

Temporal Data and Evolutionary Change

Our fourth set of coordinated readings focuses on temporal data and evolutionary change. As museum collections have become more accessible, and large-scale experiments more affordable, it is more feasible to analyze evolutionary change over long time periods now than ever before. How can we best use temporal or time-series data to understand evolutionary processes and patterns?

Discussion Questions:

In the service of that broad question, these four questions can be used as guideposts for each week’s discussions.

  • 1. How does temporal data expand our understanding of evolutionary change? What unique insights do we gain from observing the process of evolution rather than looking only at contemporary data?

  • 2. When might time series data be most useful? When might they be less useful?

  • 3. How can we use temporal data to disentangle evolutionary processes as mechanistic drivers?

  • 4. How does evolution happen in time? What is the tempo of evolution?

As always, a central goal of the RCN-ECS is to synthesize and integrate ideas about evolution in changing seas. Therefore the final week is for groups to gather together, synthesize previous discussions, and provide answers to the four questions. We encourage groups to generate bold and testable predictions and to distance themselves from simply summarizing past discussions.

We are grateful to this year’s planning committee (Dr. Malin Pinsky, Dr. Brendan Reid, René Clark, and Anthony Snead) as well as the broader RCN community for their efforts in generating topics, discussion questions, and scientific papers.

We recognize that ongoing efforts to minimize transmission of Covid-19 may lead to disruptions or delays in discussions. Please note that while we post “due dates” for discussion summaries to be posted to the Slack channel, these can be viewed as guidelines for spacing out discussions and are not hard cutoffs.

Week 1 (Deadline for discussion February 4, 2022)

Topic - Introduction to Temporal Data & Evolutionary Change

Rationale: Evolutionary time-series data can come in different shapes and lengths. These papers will help the RCN establish a shared language and familiarize members with the many forms temporal data can take.

Paper 1: (Paper and Link)

The relevance of time series in molecular ecology and conservation biology

Authors: Jan C. Habel, Martin Husemann, Aline Finger, Patrick D. Danley & Frank E. Zachos

Paper 2:

Sustained fitness gains and variability in fitness trajectories in the long-term evolution experiment with Escherichia coli

Authors: Richard E. Lenski, Michael J. Wiser, Noah Ribeck, Zachary D. Blount, Joshua R. Nahum, J. Jeffrey Morris, Luis Zaman, Caroline B. Turner, Brian D. Wade, Rohan Maddamsetti, Alita R. Burmeister, Elizabeth J. Baird, Jay Bundy, Nkrumah A. Grant, Kyle J. Card, Maia Rowles, Kiyana Weatherspoon, Spiridon E. Papoulis, Rachel Sullivan, Colleen Clark, Joseph S. Mulka & Neerja Hajela

Week 2 (February 18, 2022):

Topic - Population Dynamics and Genetic Diversity

Rationale: Population size plays a huge role in population genetic theory and is a critical factor in determining genetic diversity and the efficacy of selection. In the real world, interactions between population size, gene flow, and selection can be complex and their combined effects can be difficult to understand and predict. How can temporal genomics inform our understanding of the dynamics of fluctuating populations and population dynamics in wild systems? How are population size and neutral/adaptive genetic diversity connected, and what can temporal genomics tell us about this connection? How is genomic diversity maintained over time, particularly in small populations?

Paper 1: (Paper and Link)

The feedback between selection and demography shapes genomic diversity during coevolution

Authors: Cas Retel, Vienna Kowallik, Weini Huang, Benjamin Werner, Sven Künzel, Lutz Becks & Philine G.D. Feulner

Paper 2:

Gene flow counteracts the effect of drift in a Swiss population of snow voles fluctuating in size

Authors: Vincente García-Navas, Timothée Bonnet, Dominique Waldvogel, Peter Wandeler, Glauco Camenisch & Erik Postma

Optional Supplemental Papers:

Genetic diversity through time and space: diversity and demographic history from natural history specimens and serially sampled contemporary populations of the threatened Gouldian finch (Erythrura gouldiae)

Authors: Peri E. Bolton, Lee A. Rollins, James Brazill-Boast, Kimberley L. Maute, Sarah Legge, Jeremy J. Austin & Simon C. Griffith

Rise and fall of a wolf population: genetic diversity and structure during recovery, rapid expansion and drastic decline

Authors: E. Jansson, M. Ruokonen, I. Kojola & J. Aspi

Week 3 (March 4, 2022):

Topic: Fluctuating Selection (Short Timescales)

Rationale: Populations experience fluctuating selection at various timescales. However, fluctuations over short timescales (e.g. years, seasons) may be difficult to detect depending on selection strength/duration and species life history. Over short timescales, in which cases can we detect genomic responses to selection? How does generation length/developmental time alter our ability to detect fluctuating selection? When do genomic responses to selection fail to mirror phenotypic responses (or vice versa)?

Paper 1: (Paper and Link)

Fluctuating selection and its (elusive) evolutionary consequences in a wild rodent population

Authors: T. Bonnet & E. Postma

Paper 2:

Temporally balanced selection during development of larval Pacific oysters (Crassostrea gigas) inherently preserves genetic diversity within offspring

Authors: Evan Durland, Pierre De Wit & Chris Langdon

Week 4 (March 18, 2022):

Topic: Fluctuating Selection (Long Timescales)

Rationale: Over long timescales (e.g. decades, centuries, millenia), environmental changes can result in fluctuations in the strength and targets of selection. How does sampling breadth and availability of environmental data impact our ability to accurately characterize historic fluctuations in selection? What are some important considerations for detecting selection in fluctuating environments using genomic and phenotypic data?

Paper 1: (Paper and Link)

Inference of natural selection from ancient DNA

Authors: Marianne Dehasque, María C. Ávila-Arcos, David Díez-del-Molino, Matteo Fumagalli, Katerina Guschanski, Eline D. Lorenzen, Anna-Sapfo Malaspinas, Tomas Marques-Bonet, Michael D. Martin, Gemma G.R. Murray, Alexander S.T. Papadopulos, Nina Overgaard Therkildsen, Daniel Wegman, Love Dalén & Andrew D. Foote

Paper 2:

Linking patterns of intraspecific morphology to changing climates

Authors: Jenny L. McGuire & Daniel A. Lauer

Week 5 (April 1, 2022):

Topic: Hybridization

Rationale: It is increasingly recognized that reproductive barriers between species and adaptively differentiated populations are fluid and permeable, and that gene flow has shaped the evolution of species over time. What process determine the shape and extent of hybrid zones? How do time series data enable a better understanding of these processes? How temporally stable are hybrid zones? How might ecological factors, life history traits, and environmental change influence such stability (or lack thereof)?

Paper 1: (Paper and Link)

Evidence for concerted movement of nuclear and mitochondrial clines in a lizard hybrid zone

Authors: Adam D. Leaché, Jared A. Grummer, Rebecca B. Harris & Ian K. Breckheimer

Paper 2:

Loss of genetic diversity and reduction of genetic distance among lake trout Salvelinus namaycush ecomorphs, Lake Superior 1959 to 2013

Authors: Shauna M. Baillie, Andrew M. Muir, Kim Scribner, Paul Bentzen & Charles C. Krueger

Optional Supplemental Paper:

Physiological adaptation along environmental gradients and replicated hybrid zone structure in swordtails (Teleostei: Xiphophorus)

Authors: Z.W. Culumber, D.B. Shepard, S.W. Coleman, G.G. Rosenthal & M. Tobler

Week 6 (April 15, 2022):

Topic: Space-for-Time

Rationale: When temporal data are not available, we often turn to spatial data as a substitute. When are such replacements equivalent? When are they not? What are some inherent assumptions we make when substituting space for time?

Paper 1: (Paper and Link)

The value of space-for-time substitution for studying fine-scale microevolutionary processes

Authors: Guinevere O.U. Wogan & Ian J. Wang

Paper 2:

Fast evolution from precast bricks: genomics of young freshwater populations of Threespine Stickleback Gasterosteus aculeatus

Authors: Nadezhda V. Terekhanova, Maria D. Logacheva, Aleksey A. Penin, Tatiana V. Neretina, Anna E. Barmintseva, Georgii A. Bazykin, Alexey S. Kondrashov & Nikolai S. Mugue

Optional Supplemental Paper:

Winter storms drive rapid phenotypic, regulatory, and genomic shifts in the green anole lizard

Authors: Shane C. Campbell-Staton, Zachary A. Cheviron, Nicholas Rochette, Julian Catchen, Jonathan B. Losos & Scott V. Edwards

Week 7 (April 29, 2022)

Topic: Synthesis

Rationale: Please use this week to synthesize your discussions from the pasat 6 sets of readings and prepare answers to the overarching questions. We encourage groups to consider the discussions from the perspective of future research. Where do we go from here? Where is consensus? What areas need more research?

Diversity Statement for Coordinated Readings:

As stated in the RCN-ECS’s diversity and anti-racism statements, we value diverse perspectives and are committed to amplifying the research authored by historically under-represented groups including women, LGBTQ+ persons, non-binary persons, and Black, Indigenous, and Persons of Color (BIPOC). In keeping with this goal, we emphasized this aim in our solicitation for topic and paper nominations from the larger RCN community, purposefully requesting nominations from diverse scientists. Our organizing committee took additional steps to choose an inclusive set of papers that highlight the work of diverse scientists in these key topic areas (for example, searching for additional candidates on and Collectively, 11 out of the 16 papers included authors from non-US institutions, at least 11 papers had female-identifying authors, and at least 6 of the 16 papers included BIPOC authors. Despite these efforts, we recognize that there are limitations to our approach, and that the fields of marine science and evolutionary biology have important work to do to build an inclusive and equitable culture.