Luis Fernando Chaves

A contagious love for Nature


Nagasaki University Institute of Tropical Medicine (NEKKEN), Nagasaki 852-8523 Sakamoto 1-12-4 Japan & Programa de Investigación en Enfermedades Tropicales (PIET), Escuela de Medicina Veterinaria, Universidad Nacional, Heredia, Costa Rica. Email:

After giving it some thought, what I admire the most of John Vandermeer is his contagious love for nature. And John’s beloved nature is not a fenced forest, or any other cliché where humans are not part of the fauna, or where humans are simple background decoration in a landscape, but something that more closely resembles the feeling of finding something you like, be it a colorful bamboo mosquito or a quetzal, in a forest. That subtle moment when you somehow realize your amusement comes from your own humanity. I think from John’s love for nature emerges the many ways in which he tries to understand things and the interpenetration of his action and intellect. So, from being an ecologist developing theory and models for what he observes in nature, his love for nature also shapes his political action and stance for humanity. In this sense, I think the most integral John one will ever get to know is the one resonating with his coupled oscillator, Ivette Perfecto, and synchronizing the phase with the many comrades, most notably Jerry Smith and Catherine Badgley, when sharing all the dimensions of a common love for nature in the New World Agriculture and Ecology Group (NWAEG).

I was one of the many oscillators synchronizing the phase with John in NWAEG between 2005 and 2008. During this time I was a Ph.D. student in Ecology and Evolutionary Biology at the University of Michigan and regularly attended the NWAEG meetings. NWAEG was the best intellectual and activist community to feel comfortable by not separating politics from science, and where it was not a sin to question the “other” underpinnings of different approaches to interact with nature or modify the environment. In this community it was possible to think and act around the principle of the whole being the truth, not just what is simply convenient or what will make you famous, rich and powerful. I think the oscillations with John and the other NWAEG members helped me to question the role of forests in the transmission of parasites causing cutaneous leishmaniasis all over Latin America. Traditionally, the dogma was that cutaneous leishmaniasis was a disease that was going to disappear with the primary forests. Although a large share of the forests is gone since the 1970s, when the prophecy that deforestation was to liberate us from leishmaniasis was made, if anything this disease has become more common and widespread [1]. During my PhD, what I found was that communities in areas where forests were more abundant were less likely to be affected by the disease, and that more deforested areas not only had more leishmaniasis, but were more sensitive to climatic changes triggered by El Niño. But beyond that, what I found was that the disease didn’t map as well along any specific climatic or environmental gradient, as it followed patterns of poverty and socio-economic inequality in Costa Rica [2]. Following this work, my collaborators and I have developed a research agenda that tries to understand how poverty alters the ecology of insects vector of disease in a way that leads to different patterns of infection in a population. For example, we have looked at how housing quality can lead to important differences in the number of vectors with which people live around, or even how likely are insecticides to have an impact in reducing their abundance [3], which is associated with the probability of infection [4-6]. We have also looked at the impacts of land use change on vector infection [7] and the impacts of poverty on the health of other animals with which we closely interact and share parasites [8-10], and ultimately an interest on the implications of poverty in the ecology of disease transmission. This integral view of things has been only possible under the influence of John and the NWAEG.

Along these lines, from the time of my Ph.D. and the interaction with John, I always wanted to model the dynamics of latifundia[1] formation as influenced by the presence of a disease. John was among the few people that also found this idea “exciting and cutting edge” and encouraged me to pursue its mathematical modelling. The idea that latifundia formation were partially driven by disease transmission was cleverly exposed by Angelo Celli in his study about the historical dynamics of malaria transmission in the Roman Campagna [11], and I hesitated to do anything worrying the problem was historical and probably local in nature. However, after several years, and the discovery that inequities in land tenure, not the beauty of Yang Guifei[2], were to be blamed for the collapse of the T’ang dynasty in China, I got the courage to develop a model that coupled land use dynamics and land tenure and that was able to reproduce the patterns of latifundia formation described by Celli [12]. Which was interesting, since a basic take home message from that model was that inequities in access to health can create poverty … Yet, things can always be more dynamic, entangled and full of contradictions requiring new synthesis, but as starting point, as a first abstraction of a complex phenomenon, I decided to present this study [12] during John’s celebratory symposium and highlight that in this Festschrift, since this piece of work owes much to John influence.

On a more human side, from John I also got numerous pieces of valuable advice, the most important about seeking the truthfulness in the words of those that, purposefully or inadvertedly, may hurt us. Also, by following John’s example, I am now naturally able to do simple things that reduce gender, race and any kind of artificial gaps in society and make any environment more inclusive and enjoyable, or at least I have been told so.

Finally, I want to thank John and his coupled oscillator, Ivette, for being such great friends and mentors. I probably will never get to exhibit John’s contagious enthusiasm about things, but I am thankful that after meeting him I feel more comfortable about the way in which I love nature myself, its wholeness, contradictions and our power to change things and move forward to a new stage were science is not used to justify atrocities and where science helps to improve the lives of people without compromising our unity with nature.


  1. Alvar J, Vélez ID, Bern C, Herrero M, Desjeux P, Cano J, Jannin J, Boer Md, the WHOLCT: Leishmaniasis Worldwide and Global Estimates of Its Incidence. PLoS One 2012, 7(5):e35671.
  2. Chaves LF, Cohen JM, Pascual M, Wilson ML: Social Exclusion Modifies Climate and Deforestation Impacts on a Vector-Borne Disease. Plos Neglect Trop Dis 2008, 2(2):e176.
  3. Chaves LF, Calzada JE, Rigg CE, Valderrama A, Gottdenker N, Saldaña A: Leishmaniasis sand fly vector density reduction is less marked in destitute housing after insecticide thermal fogging. Parasites & Vectors 2013, 6(1):164.
  4. Saldaña A, Chaves LF, Rigg CA, Wald C, Smucker JE, Calzada JE: Clinical Cutaneous Leishmaniasis Rates Are Associated with Household Lutzomyia gomezi, Lu. panamensis, and Lu. trapidoi Abundance in Trinidad de Las Minas, Western Panama. The American Journal of Tropical Medicine and Hygiene 2013, 88(3):572-574.
  5. Chaves LF, Calzada JE, Valderama A, Saldaña A: Cutaneous Leishmaniasis and Sand Fly fluctuations are associated with El Niño in Panamá. Plos Neglect Trop Dis 2014, 8:e3210.
  6. Yamada K, Valderrama A, Gottdenker N, Cerezo L, Minakawa N, Saldaña A, Calzada JE, Chaves LF: Macroecological patterns of American Cutaneous Leishmaniasis transmission across the health areas of Panamá (1980–2012). Parasite Epidemiology and Control 2016, 1(2):42-55.
  7. Gottdenker NL, Chaves LF, Calzada JE, Saldana A, Carroll CR: Host life history strategy, species diversity, and habitat influence Trypanosoma cruzi vector infection in Changing landscapes. PLoS Negl Trop Dis 2012, 6(11):e1884.
  8. Fung HL, Calzada J, Saldaña A, Santamaria AM, Pineda V, Gonzalez K, Chaves LF, Garner B, Gottdenker N: Domestic dog health worsens with socio-economic deprivation of their home communities. Acta Tropica 2014, 135(0):67-74.
  9. Calzada JE, Saldaña A, González K, Rigg C, Pineda V, Santamaría AM, Rodriguez I, Gottdenker N, Laurenti MD, Chaves LF: Cutaneous Leishmaniasis in dogs: is high seroprevalence indicative of a reservoir role?Parasitology 2015, 142(9):1202-1214.
  10. Saldaña A, Calzada JE, Pineda V, Perea M, Rigg C, González K, Santamaria AM, Gottdenker NL, Chaves LF: Risk factors associated with Trypanosoma cruzi exposure in domestic dogs from a rural community in Panama. Memórias do Instituto Oswaldo Cruz 2015, 110(7):936-944.
  11. Celli A: The history of malaria in the roman campagna from ancient times. London: John Bale, Sons & Danielsson, Ltd.; 1933.
  12. Chaves LF: The Dynamics of Latifundia Formation. PLoS One 2013, 8(12):e82863.


[1] Accumulation of land ownership by a small fraction of the people working the land.

[2] One of the four classical Chinese beauties, so beautiful that all flowers will be put in shame.