Emergent patterns in nature and society

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Mapping regime shifts

The regime shifts database (RSDB) is to my knowledge the largest repository of information about regime shifts in the world. It synthesises scientific literature about known social-ecological regime shifts that can have impacts on ecosystem services. I always think of it as a Wikipedia of regime shifts: a public online repository where people can go and learn what are they about, but also contribute content and cases.

Lead by Oonsie Biggs and Garry Peterson at the Stockholm Resilience Centre, the database started as an internship I did as master student in 2009. Later it became my master thesis and soon after the core of my doctoral studies. Several master thesis have been published using the database and it has also been useful for international assessments of regime shifts. It contributed to Global Biodiversity Outlook 3 (2010), the Arctic Resilience Assessment (2016), and more recently I was asked to contribute a short synthesis for IPBES – the International Panel for Biodiversity and Ecosystem Services.

Despite its importance, at least on my eyes, the regime shift database is largely unknown to the scientific community. There is no published peer reviewed paper describing how it was done and how can it be used. As a result, few groups have been publishing work suggesting that a framework for comparing regime shifts is needed, in other words: reinventing the wheel. The first public available draft of that paper is included on my Licenciate thesis (2013), and a later edited pre-print was posted on bioRxive (2015) that was included on my PhD thesis. I needed to graduate. Unfortunately, it has never been submitted for peer-review and people keep using the database without knowing how to give proper recognition to our work. The draft has been sitting on Oonsie’s desk for literally years waiting for the submit button to be pressed.

To date the database describes 30 generic types of regime shifts and 324 case studies, plus a few experimental cases that if included add up to 35 regime shift types. A generic type is for example the coral reefs transitions from coral dominated reefs to macro-algae or other alternative stable states; while a case study would be the coral transitions in Jamaica. A generic type is a collection of all drivers and mechanisms that can produce a particular regime shift, while a case is an instance of its occurrence. An analogy that often helps me distinguish them is the one of a disease (generic type) and the patient (case). Such was my enthusiasm with this project that out of the 30 regime shifts currently available, 16 were contributed by me during the first year of my PhD. Most case studies were contributed by my friend and colleague Johanna Yletyinen (@jo_yletyinen) who spent a lot of time digitalising the Hypoxia database made available by the study of Diaz and Rosenberg in Science (2008). The rest of the contributions have been developed in the class room with master students or researchers who have been generous to share their work with us by filling up a data template. Roughly 1000 scientific publications have been reviewed to build the database.

Last week writing the synthesis for IPBES made me think that we need better visualisations of the RSDB. I created a map where large dots represent generic types or regime shifts. The are located on the kind of ecosystem where they would be expected to occur. So for example, fisheries collapse is located on the southern ocean close to Antarctica (a place where many fish stocks have been reported on be in decline), but a case study about salmon appears on the other side of the planet in Alaska. Case studies are the small dots on the same colour as their generic types. You can see all the hypoxia cases that Johanna coded especially on the coasts of Europe, North America and Japan. Creating the map brought memories of my days writing regime shifts reviews for the database. It also made me realise that it has been few years I have not contributed besides my teaching duty. Disappointed by the lack of commitment with the paper, my PhD student enthusiasm almost disappeared. The last draft I worked on was on desertification (2014?), it was never reviewed nor published online. Each contribution to the RSDB has been peer reviewed by an expert on the topic to make sure we do a fair assessment of the literature.  Here is the map:RSDB_map.png

Currently I live in the United States, Princeton to be precise. It’s not a secret for anyone who follow the news -or try to avoid them like me- that the political situation here is concerning, to say the least. The kind of situation when you ask yourself what can I do? How do I contribute to make this a better place. Scientist being censored, immigration policies that not only contradict the USadian heritage of immigrants but also remind us of a one of the darkest moments of human history. Whatever I could think of seems insignificant.

Then I looked the map again and tried to remember what was my driver when contributing to RSDB. It was making knowledge free for others to be used, the kind of thing that doesn’t contribute to your career but hopefully is doing some good somewhere. If you come from a place such as the one I come from, you know that scientific knowledge is locked behind paywalls and most of people do not have access to scientific literature. Documenting change in ecosystems and making available to a broader public was important to me. It was like sending wealth to someone else, no on the form of money but knowledge, making sure it’s available when is needed, for free. A lot of people is marching for life and standing up for science. My way of contributing will be by putting dots on the map, making scientific facts count and visible when needed. From now on every week I will contribute a case to RSDB. Let’s make science count. If you want to contribute just drop me a line.

 

 

 

Book review: Alguien tiene que llevar la contraria

alguien-tiene-que-llevar-la-contraria-500x500Mis vacaciones este año en Colombia fueron cortas y por tanto elegí un libro que se veía corto pero sustancioso. “Alguien tiene que llevar la contraria” es una colección de 12 ensayos escritos por Alejandro Gaviria, el actual ministro de salud de Colombia. El título me viene como anillo al dedo, pero en verdad lo que me cautivo fue el autor. Yo conocí a Alejando en 2008 cuando el era decano de Economía en la Universidad de los Andes y yo comenzaba a trabajar como asistente de investigación en el grupo del economista ambiental Jorge Maldonado. Alejandro Gaviria, como varios de mis profesores modelo (e.g. Garry Peterson, Juan Camilo Cárdenas) comenzó su carrera como Ingeniero. Luego hizo su doctorado en Economía en la Universidad de California, y aunque escribe y piensa como economista, también ha hecho carrera como columnista en periódicos nacionales,  ha escrito varios libros, mantiene un blog, y ha recibido premios por su labor como investigador, docente, y periodista. En resumen, es una persona que no solamente es un buen académico, también es un buen comunicador y ha tenido el coraje de pocos de hacer la transición de escribir artículos científicos a políticas publicas. El libro, ya en su cuarta edición tan solo tres meses después de la primera, está catalogado por la editorial como ‘sociología’. Ahi fue cuando me pregunte: cómo lo hace?

El libro se divide en tres secciones. La primera titulada ‘Liberalismo y cambio social’ tiene un matiz mucho mas filosófico y literario. Son un conjunto de reflexiones valiosas sobre que es la democracia, sus limitantes, el conflicto y su valor como motor de cambio social, al igual que la importancia del escepticismo. Esta primera parte muestra el aprecio que Gaviria tiene por la literatura y como el contar historias nos ayudan a imaginar futuros y criticar presentes. Me gusto mucho como resalta el valor del conflicto en la sociedad, respetuoso y necesario, al igual que el valor del escepticismo, una practica imprescindible en el quehacer científico.

La segunda parte es sobre hechos y palabras. Tiene un matiz mucho mas histórico y es muy rico en detalles del contexto colombiano. Comienza evaluando la evolución de la desigualdad en Colombia y el apogeo de las ideologías Marxistas en los países latinoamericanos. Continua con una breve reseña del Darwinismo en Colombia, de como las ideas evolutivas fueron en un principio rechazadas y finalmente aceptadas en nuestro país.  Introduce también la historia de la ‘meritocracia’, un termino acuñado por Michael Young en 1958 cuyo significado se ha transformado en algo menos negativo de lo propuesto por el autor de El ascenso de la meritocracia. Gaviria retoma su significado original y advierte de sus consecuencias negativas en la division de clases sociales y en ultimas el aumento de la desigualdad. Por ultimo, el autor revista la historia de la guerra contra las drogas en Colombia con una colección buenísimas de referencias para el lector interesado.

La tercera parte fue mi favorita. Gaviria cierra el libro con ensayos mas académicos basados en hechos y estadísticas del progreso social en Colombia y otros países latinoamericanos. Entre otros temas, trata la disminución de la pobreza, un análisis de movilidad social y por ultimo una critica a la ‘crisis’ de salud publica. Gaviria es cauto al advertir que es largo el camino por recorrer, pero a la vez sincero en dejar claro que progreso si ha habido, mas social que económico, pero definitivamente no es negligible. Lo que me gustó fue el aire de realismo optimista que se respira entre sus lineas. Llama al colombiano a criticar la realidad desde los hechos, a no darnos palo tan duro y de gratis, y darnos cuenta que si se puede. Gaviria deja ver aqui y allá su pasión por la literatura, sus gustos y disgustos ideológicos y politicos, así como los dilemas éticos que enfrenta como funcionario público. Al final de cuentas es un ser humano como cualquier otro que a travez de su escritura invita a repensar el país y la época que nos toco vivir de una manera diferente, al menos constructiva.

 

 

“Me too” social science is not fighting inequality

In late spring 2016 I joined the “Beijer Young Scholars”, a vibrant group of PhD students and junior postdocs that gathered in a small island in the Stockholm archipelago to think about inequality and the biosphere. Discussions were heated, disagreements were common, from what the concept means from different disciplinary lenses, how to measure it, how to approximate or even define a research problem, and how to be aware of our own prejudices when we approach the topic. Yet it has been a rewarding learning experience that I hope will continue to provide sources of inspiration, healthy disagreements and skepticism. A note on myths of inequality for future conversations were found on a blog by Kevin Leicht, Professor of Sociology at University of Illinois Urbana-Champaign. That’s why here are his words reblogged:

Work in Progress

Outsourced

by Kevin T. Leicht

Sociology is at risk of losing what credibility it has because we have latched onto ways of studying inequality that are not suited to new economic arrangements.

What are those ways? They started as truths that now represent half-truths or worse – we just repeat them and think we’re doing something to produce insights into how inequality is produced and maintained.

We can’t end inequality by closing group gaps

Let’s start with the most basic of these habits and beliefs – The belief that most social inequality is tied to race and gender. Empirically this is not true and it hasn’t been for at least thirty years.

There is far more social inequality within demographic groups than there is between them.

There is overwhelming evidence to support this claim. The ratio of mean household income in the top 5 percent to the mean household income in…

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Behavioural Experiments in Social-Ecological Systems with Thresholds

Here are the slides and abstract of my talk at the conference of complex systems in Amsterdam:

 

How does people behave when dealing with situations pervaded by thresholds? Imagine you’re a fisherman whose livelihoods depend on a resource on the brink to collapse, what would you do? and what do you think others will do? Here we report results form a field experiment with fishermen from four coastal communities in the Colombian Caribbean. A dynamic game with 256 fishermen helped us investigate behavioural responses to the existence of thresholds (probability =1 ), risk (threshold with a climate event with known probability of 0.5) and uncertainty (threshold with an unknown probability climate event). Communication was allowed during the game and the social dilemma was confronted in groups of 4 fishermen. We found that fishermen facing thresholds presented a more conservative behaviour on the exploration of the parameter space of resource exploitation. Some groups that crossed the threshold managed to recover to a regime of high fish reproduction rate. However, complementary survey data reveals that groups that collapsed the resource in the game come often from communities with high livelihood diversification, lower resource dependence and strongly exposed to infrastructure development. We speculate that the later translates on higher noise levels on resource dynamics which decouples or mask the relationship between fishing efforts and stock size encouraging a more explorative behaviour of fishing effort in real life. This context is brought to our artificial game and leave statistical signatures on resource exploitation patterns. In general, people adopt a precautionary behaviour when dealing with common pool resource dilemmas with thresholds. However, stochasticity can trigger the opposite behaviour.

Cascading effects of critical transitions in social-ecological systems

For those who miss the talk, here is the slides and the abstract.

 

Critical transitions in nature and society are likely to occur more often and severe as humans increase they pressure on the world ecosystems. Yet it is largely unknown how these transitions will interact, whether the occurrence of one will increase the likelihood of another, and whether these potential teleconnections (social and ecological) correlate critical transition in distant places. Here we present a framework for exploring three types of potential cascading effects of critical transitions: forks, domino effects and inconvenient feedbacks. Drivers and feedback mechanisms are reduced to a network form that allow us to explore drivers co-occurrence (forks). Sharing drivers is likely to increase correlation in time or space among critical transitions but not necessarily interdependence. Random walks on causal networks allow us to detect and compare communities of common drivers and feedback mechanisms across different critical transitions. Domino effects and inconvenient feedbacks were identified by mapping new circular pathways on coupled networks that have not been previously reported. The method serves as a platform for hypothesis exploration of plausible new feedbacks between critical transitions in social-ecological systems; it helps to scope structural interdependence and hence an avenue for future modelling and empirical testing of regime shifts coupling.

ESA: Regime Shifts in the Anthropocene

Last year I was supposed to present this talk at ESA100 but a delayed visa made me miss the opportunity to share the main results of my PhD with the ecological society of America. This year and with the support of the PlosONE early career travel awards, I’m presenting my talk Regime Shifts in the Anthropocene at ESA101 in Fort Lauderdale. Here are the slides and the abstract of my talk.

 

Abstract:

Human action is driving worldwide change in ecosystems. While some of these changes have been gradual, others have led to surprising, large and persistent ecological regime shifts. Such shifts challenge ecological management and governance because they substantially alter the availability of ecosystems services, while being difficult to predict and reverse. Assessing whether continued global change will lead to further regime shifts, or has the potential trigger cascading regime shifts has been a central question in global change policy. Addressing this issue has, however, been hampered by the focus of regime shift research on specific cases or types of regime shifts. To systematically assess the global risk of regime shifts we conducted a comparative analysis of 25 types of regime shifts across marine, terrestrial and polar systems; identifying their main drivers, and most common impacts on ecosystem services. We use network analysis to demonstrate that regime shifts share clusters of direct and indirect drivers that shape opportunities for management.

While climatic change and food production are common drivers of regime shifts, drivers’ diversity undermine blue print solutions. Drivers co-occurrence vary with management scale and ecosystem type. Subcontinental regime shifts have fewer drivers related to climate; aquatic regime shifts share more drivers, often related to nutrient inputs and food production; while terrestrial regime shifts have a higher diversity of drivers making their management more context dependent. Given this variety of drivers, avoiding regime shifts requires simultaneously managing multiple types of global change forces across scales. However, there are substantial opportunities for increasing resilience to global drivers, such as climate change, by managing local drivers. Such coordinated actions are essential to reduce the risk of ecological surprises in the Anthropocene. Because many regime shifts can amplify the drivers of other regime shifts, continued global change can also be expected to increase the risk of cascading regime shifts. Nevertheless, the variety of scales at which regime shift drivers operate provides opportunities for reducing the risk of many types of regime shifts by addressing local or regional drivers, even in the absence of rapid reduction of global drivers.

Book review: Phase Transitions

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Phase Transitions by Ricard Solé was one of those books that nurtured my curiosity and motivated me to carry on with my PhD. Ana, my girlfriend at the time (2011), always suggested me to bring nice books for holidays that would distract me from work, books with stories or authors from the places we were visiting . But with Solé it was difficult to leave it at home. Most of the book was read in 2012-13 on the beaches and bars of Barcelona, Solé’s home; and believe or not, it did distracted me from work by making me looking it from a different perspective.

Phase Transitions is the concept that physicist like Solé use to describe changes in dynamic systems with bifurcations – changes between different states of organisation in complex systems. It’s the same as ‘critical transitions’ or critical phenomena, as other authors like Marten Scheffer prefer to use; or ‘regime shifts’ as ecologist often call them. But that’s just jargon. I read the book too long ago to be able to give a fair summary and highlight its most important lessons. However, this review will be more from an emotional perspective, what I like and dislike from that bunch of math.

The book is an amazing resource for teaching. It’s structured in 16 very short chapters, most of them don’t exceed the 10 pages. Yet they cover as many disciplines as you can imagine, it’s like brain candy for an interdisciplinary inclined mind. Chapter 1-5 set up the basics: what are phase transitions, analysis of stability and instability, bifurcations, percolations and random graphs. Solé keeps the mathematics to a minimum, any student without a strong maths background like me follows and enjoy more the story that the mathematical subtleties. He also guide you on how the math or the set of equations that helps you understand something, say percolations, are also useful to understand what looks like unrelated topics  such as cancer dynamics or lexical change in a language.

And that is exactly what I like of the book. Chapters 6 – 16 takes you on a journey of where phase transitions have applications in different fields in science: the origins of life (6), virus dynamics (7), and cell structure (8) for the biology inclined.  For the medicine inclined: epidemic spreading (9), gene networks (10), and cancer (11). For someone like me: ecological shifts (12), social collapse (16), information and traffic jams (13) and collective intelligence (14). And my absolute favourite: language (15) because it surprised me how phase transitions can be used to understand change in language, and also because it introduced a very peculiar model called the hypercube. Now what I dislike of the book was the incomplete list of references, imagine if the one missing is the one you want to follow up!

I took the book out of the shelf today and look at it with nostalgia. Last week I read a paper that studies depression as a critical transition using models of symptoms networks with thresholds (co-authored by Scheffer, the author of the book that inspired this blog), and today I accidentally ended up watching the video below on how music can also have basins of attraction. That feeling of déjà vu, that two disparate fields can have something fundamental in common, that we can learn music and better understand depression or cancer and viceversa; that’s what makes me in love with science. That’s what I enjoyed the most of Solé’s book, it opened the horizon of what I was actually doing on my PhD and helped me feel less afraid of exploring; otherwise how does one make the nice connections?