The fields of agroecology and ecological evolutionary developmental biology (eco-evo-devo) have been performing somewhat parallel efforts of synthesis. On the one hand, agroecology has incorporated knowledge from different disciplinary sources, among which are of course ecology, agronomy and, in a less extent, other scientific disciplines. It has also embraced local and traditional agricultural knowledge. On the other hand, during the last decades a large effort has aimed to integrate diverse theories, evidence and tools from ecology, developmental and evolutionary biology in what has been called eco-evo-devo. In this article we argue that these ongoing processes of synthesis can feedback each other with valuable theoretical and practical frameworks, as well as with questions and challenges that can push each other’s borders. We conclude that the interaction between these two fields can provide a critical view of current conservation and agricultural policies and practices, for instance those related to germplasm conservation, and can help to tackle some of the open questions that are being addressed by the sciences, practices and social movements converging in agroecology.
Los campos de la agroecología y de la ecología evolutiva del desarrollo (eco- evo-devo) han llevado a cabo esfuerzos de síntesis que hasta ahora han avanzado en paralelo. Por un lado, la agroecología ha incorporado el conocimiento de distintas fuentes disciplinares, entre las cuales están desde luego la ecología y la agronomía y, en menor medida, otras varias disciplinas científicas. La agroecología también ha incorporado parte del conocimiento agrícola tradicional. Por otro lado, durante las últimas décadas se han articulado diversas teorías, evidencia y herramientas de la ecología, la biología evolutiva y la biología del desarrollo en lo que se ha llamado eco-evo-devo. En este artículo argumentamos que estos dos procesos de síntesis pueden retroalimentarse desde sus valiosos marcos teóricos y prácticos, así como con preguntas y desafíos que lleven a empujar mutuamente las fronteras de la agroecología y del eco-evo-devo. Concluimos que la interacción entre estos dos campos puede proveer de una visión crítica hacia las estrategias de conservación y de producción agrícola, por ejemplo, de aquéllas relacionadas con la conservación del germoplasma, y que además puede ayudar a abordar algunas de las cuestiones que la agroecología trabaja en sus ejes de ciencia, práctica y movimiento social.
AGROECOLOGY is an intrinsically transdisciplinary field. Not only does it feed from ecology, agronomy, anthropology, economy, among other disciplines, but it encompasses a set of practices and principles that have been developed in collaboration with organized peasants and small farmers. Indeed, agroecology is often understood along three axes: as a science, as a set of practical techniques and as a social movement vindicating the right to food sovereignty (
As a science emerging around 1930, agroecology aimed to understand cultivated plant systems as ecosystems, as well as to apply ecological concepts and methods to their study and improvement (
Among the principles behind agroecology some are: i) to base its practice and technologies on the processes enabled by biodiversity, rather than on external, often oil-dependent inputs; ii) to foster productivity by using locally adapted plant varieties; iii) to pursue the local management of common resources and the maintenance of local biogeochemical processes, instead of following extractive approaches; iv) to favor the recreation and reproduction of local biocultural heritage and to incorporate it into its practices and knowledge, and, v) to approach agroecosystems from an integrative, socio-ecosystemic view (
The objectives and ways of agroecology have recently been introduced to different academic and political contexts, and some of the key components of what we consider as agroecological science, practice and movement are at risk of being diluted or lost (
Agroecology is currently a source of open questions and challenges that are pushing for a more integrative understanding of living beings, ecosystems and, specifically, of cultivated plant systems. In this section we put forward some of these questions and challenges.
In spite of its integrative nature, agroecology carries some limitations that might have been inherited from the disciplines that nurture it, biology in particular. Agroecology has adopted a critical position towards reductionist approaches to agriculture, deeply questioning the target-problem strategies (pests, soil limiting nutrient, etc.) and the emphasis on productivity of industrial agriculture (
For example, agroecology closely interacts with research programs on plant and animal domestication. Domestication has occurred in complex socio-ecological contexts (e.g.,
We will elaborate on this issue in the next section, but it is worth noting that a reduced view of domestication clearly affects the way in which agroecologists may conceptualize the
On the other hand, current studies in agroecology are pushing for more integrative biological sciences. For instance, it has recently been uncovered that properties at the landscape scale can modify plant phenotypes at the single- plot scale (e.g.,
Some of the ongoing agroecological strategies aiming to conserve or recover soil quality are based on processes involving whole biological communities and organism-environment interactions. An example of this is the use of the so- called efficient or effective microorganisms, which are whole soil microbial communities incorporated to cultivated soils (
Overall, in the context of social and environmental crises and rapid environmental changes, agroecology requires a deeper understanding of the biological and social processes that confer resilience to agroecosystems (
Finally, the deep social roots of agroecology are motivating biological sciences, which have historically kept social factors apart from their research questions, to take into account the socio-ecological environment of living organisms. This might be the case of developmental and evolutionary biology (see below), which could greatly deepen its understanding of development and evolution when tackling questions such as: Do maize plants develop similarly in monoculture and in association with beans and squash, as maize has traditionally been grown in Mexico and Central America? Is the appearance and fixation of traits associated to domestication more likely in either of these two conditions? If so, what are the mechanisms behind this?
The recent integration of concepts, methods and interdisciplinary research from developmental biology and ecology into evolutionary theory has resulted in the emergence of ecological evolutionary developmental biology (eco-evo- devo) (
As we will argue throughout this text, the concepts and methods bringing together development, ecology and evolution can function as contact points and help establish a powerful feedback with agroecology. This seems like a promising association in Latin America, where a vigorous community working on evo-devo and eco-evo-devo and many agroecological movements coincide (Brown
Phenotypic plasticity can be understood as the output of an organism’s development in its interaction with environment. When it is observed in embryonic or larval stages of plants and animals it is often called developmental plasticity (
Phenotypic and developmental plasticity can be illustrated by countless examples in different taxa. For instance, the same plant population can develop completely different leaves depending on whether plants develop below or above water, or can modify the size and architecture of its roots depending on nutrient availability and other soil conditions. This phenomenon has also been studied in some plants of agricultural interest (e.g.,
A valuable tool to study and characterize phenotypic plasticity is the reaction norm, which describes the pattern of phenotypic expression for a single genotype in an environmental gradient. Reaction norms thus help visualize and measure the way organisms change their morphology, behavior or physiology when they develop in different environmental conditions. Reaction norm experiments have shown that plasticity may not always lead to adaptive phenotypes and that plastic changes might exhibit different patterns for different environmental factors (e.g., temperature, nutrient and water availability, etc.) (Vía
It is worth noting that, while plasticity studies and reaction norm analyses draw on
quantitative genetics, eco-evo-devo has added an explicit focus on the genetic,
cellular and organismal mechanisms that interact with the environment, bringing
ecological causes and a process-based view to the heart of developmental and
plasticity studies (
Biological evolution requires phenotypic variation, since it is on the basis of non-neutral variation that novel phenotyes might be selected and fixed in populations. A current avenue of active research in eco-evo-devo involves the question of whether phenotypic variation generated by plasticity can precede or facilitate evolutionary change. This question has remained controversial because the modern evolutionary synthesis considers genetic change, mainly genetic mutations, as the most relevant source of variation in biological populations. However, theory and growing empirical evidence show that plasticity-first evolution is possible and suggest that it might be important in natural populations (West-Eberhard 2013;
The proposed mechanisms behind plasticity-first evolution are more than one and are explained
elsewhere in detail (e.g.,
Interestingly, this type of process could be accelerated or reinforced by extragenic inheritance, this is, inheritance that can occur owing to diverse molecular, ecological and social processes that do not involve genetic inheritance (
As it is the case in Agroecological research, there are current challenges and open questions in eco-evo-devo that could stimulate the dialogue between these two fields. The questions that we will consider here are mostly related to the role of plasticity in the ecological and evolutionary dimensions of organismal development.
A recent meta-analysis shows that approximately one fourth of the total trait variation within plant communities is due to variation within species (
One of the challenges in testing for plasticity-first evolution is finding suitable study systems in natural populations (
Similarly, many of the processes involved in the expression and evolution of plasticity have been described in model organisms in laboratory or greenhouse conditions, going from the classical experiments of C.H. Waddington with fruit flies to the ongoing studies in a few other animal and plant species (e.g.,
Another open question in eco-evo-devo is what the conditions that select or favor the evolution of plasticity are. Answering this question will require joint theoretical and experimental approaches (e.g.,
Finally, it has been convincingly argued that science in general benefits from widening its scope of sources of knowledge and evidence (e.g.,
For instance, there is a Japanese agricultural practice known as mugifumi, which consists on the mechanical stimulation of the seedlings of wheat and barley by treading. As 17th century sources confirm, Japanese farmers have known for centuries that treading prevents spindly growth, strengthens the roots, increases tillers and ear length, and eventually increases yield (
In a bidirectional interaction between academia and other social actors, it is also necessary to ask how knowledge and research in eco-evo-devo can back social movements towards food sovereignty, social and environmental justice, and sustainability. So far, research in eco-evo-devo has already accompanied or advised some social struggles to conserve cultural and biological diversity (various chapters in
In this section we will comment on potential feedback interactions between Agroecology and eco-evo-devo, in particular in setting up common model systems. To this end, we will consider phenotypic plasticity and multiscale, multispecies interactions as possible contact points.
In spite of plasticity’s importance as a cause for ecologically and evolutionary relevant variation (almost any biologist will acknowledge the prevalence and significance of plasticity), it has often been treated as a nuance and has not usually been considered in experimental designs or research questions (Robert 2002; although see examples of exceptions in
Agroecosystems provide a great setting to study phenotypic plasticity and eco-evo-devo questions. In particular, traditional agroecosystems constitute invaluable model systems. First, these systems are often practiced as polycultures in thousands or millions of plots in diverse environmental conditions (e.g., maize cultivation in Mexico ranges from 0 mamsl to more than 2200 mamsl; see relevant work by
On the side of the agroecological sciences, practices and social movements, the knowledge that eco-evo-devo can provide about the diverse processes involved in plant domestication and breeding can inform the in-field practices for plant management, as well as for seed selection and conservation. Moreover, integrative research in biological sciences can allow to explore questions such as: i) the effect of multiple ecological interactions (e.g., bacteria-plant-pollinator) on the response of cultivated plants to environmental stress along one or more plant generations; ii) the effect of multiscale ecological interactions on the yield, resilience and vulnerability of agroecosystems; how does land use around a plot affect cultivated plants inside the plot?, how can a group of producers organize to configure their shared territory as best as possible in terms of agroecosystemic yield and resilience?, and, iii) the genetic, social and environmental conditions that favor the plastic and adaptive response of plants and of the whole agroecosystems in the face of different perturbations.
The
There is some ongoing work on the directions sketched here. In particular, a project based at Mexico’s National University is aiming to study the biological and social processes behind the great diversity of domesticated varieties of chili pepper (
As mentioned above, most of the extant agrobiodiversity has been generated in traditional agroecosystems by intricate developmental, ecological, evolutionary and social processes. Moreover, this agrobiodiversity is part of the biocultural heritage of millions of small farmers and peasants around the world, who in turn recreate their identity and culture around such diversity of domesticated plants and animals (
This in turn leads to the loss of an incommensurable amount of non-cultivated plants, livestock and wild species that are associated to these varieties and whose temporary or permanent establishment is allowed only in certain types of agriculture (FAO Website for Agrobiodiversity 2017; Perfecto
In the context of such agrobiodiversity crisis, different strategies have been adopted by different sectors of the society. On the one hand, several governments and corporations have favored the establishment of large, highly secured seed and germplasm banks that aim to protect the existing seeds in the case of catastrophes or global crises (see Svalbard Global Seed Vault Website). While this type of effort might be necessary, depending on who has access to the secured diversity, this approach is largely insufficient, as it can be argued both from the agroecological and eco-evo-devo perspectives sketched above.
Since the seeds and germplasm are by definition the carriers of the genetic information of a given organism, it is plausible from a gene-centric view to conserve the varieties and species of interest from their seeds or germplasm. However, rather than copied or decoded from their genetic information, organisms are
It results thus limited to aim only at the conservation of germplasm of varieties whose cultivation and use rely on local techniques and knowledge that, if not practiced or not meaningful, are lost. It could be said that seed and germplasm bank strategies aim to save a hypothetical essence of the desired species and varieties -an essence questionably deposited on the genes-, rather than guarantee that the processes and livelihoods that have generated them, and that could generate many more, can continue to occur (Jardón Barbolla and Benítez 2016).
In contrast with these conservation strategies, peasant movements in the world refuse to keep our biocultural heritage in museums and banks, and aim to guaranteeing the conditions that allow peasants to live with dignity and to continue to take part in the evolutionary processes that have created agrobiodiversity. In its social axis, agroecology has incorporated and designed diverse social practices and techniques that allow for collaborative learning and experimentation among peasants, students, technicians and researches, and that can sometimes be more useful in the process of building food sovereignty than the agroecological techniques themselves (P. Rossett in Escuela Campesina Multimedia).
The “campesino to campesino” and “participatory action research” frameworks are good examples of such approach and involve a set of well-described principles and techniques (workshops, research protocols, social organization schemes, etcetera) that could guide work in different agricultural contexts (Escuela Campesina Multimedia,
Agroecology and eco-evo-devo have and can learn from this scenario more than it might seem at first sight. Performing scientific research in collaboration with organized groups of producers can entail a degree of freedom and possibilities that are ever more unusual in the academic context. It becomes possible in this context, for example, to perform large-scale and long-term experiments that are also of interest for the producers, and that might be extremely difficult to pursue via the standard academic avenues. Local knowledge, needs and questions have nurtured agroecology and could enrich eco-evo-devo research in valuable and unexpected ways.
In the face of the current crisis of biodiversity and agrobiodiversity loss, climate change and persisting hunger, it might seem that the “simple” methods to guarantee food sovereignty have already been applied and that new technological developments and ever more secure seed banks are the only way to follow. Nevertheless, considering the lessons learned from eco-evo-devo and agroecology, as well as the overwhelming fact that around 70% of the food humans consume is produced by small farmers and peasants, who have access to 30% of the land and water resources (
I would like to thank members of the “Seminario de Agroecología y Domesticación” at ceiich-unam, members of the laboratory “LaParcela” at lancis-ie-unam and members of “El Molote Agroecológico”. I would also like to thank Naomi Nakayama for bringing to my attention the practice of