Under Foreign Skies: Thomas van der Hammen

This programme is part of the series Under Foreign Skies
Thomas van der Hammen
Thomas van der Hammen

“Under Foreign Skies” is a series of portraits of Dutch people abroad doing remarkable things.

Thomas van der Hammen (1924-2010) was one of the world’s leading experts on biodiversity in Colombia. The South American nation covers less than 1% of the world’s land surface, yet it is home to 15% of the Earth’s plant species. The 79-year-old professor first visited the South American nation in the early 1950’s ,and he returned regularly over the next half century before finally settling there. In this wide-ranging interview, he spoke about his research and his life-long fascination with Colombia.

Producer: Eric Beauchemin

Broadcast: November 20, 2003


Radio Netherlands presents “Under Foreign Skies”, portraits of Dutch people doing remarkable things. The programme is presented by Eric Beauchemin.

I hope to finish before I’m 80 with these books at least. But still there’s always something to do. If the work you are doing in nature is something you do because you like to do it. I love nature.

Professor Thomas van der Hammen obtained his doctorate in biological geology from the University of Leiden in the early 1950’s. A few months later, he made his first trip to Colombia, a country that continues to fascinate him over half a century later. Professor van der Hammen has become one of the world’s leading experts on biodiversity in Colombia. The South American nation covers less than 1% of world’s land surface, yet it’s home to 15% of the earth’s plant species. I met him at his home in the savannah plains north of the Colombian capital Bogotá. It’s a sprawling property that he’s converted into a mini nature reserve. Professor van der Hammen, who is now 79, told me he was first invited to go to Colombia to participate in a geological survey.

It attracted me very much. I wanted to be in nature. I wanted to know the Amazon area. I wanted to know the Andes. So, it was quite an opportunity for me and I said, ‘well, yes, I accept’. So, I signed a few months later in ’51, I signed a contract and I came to Colombia. EB: You said you were particularly interested in the Andes and the Amazon. You obviously went to both regions. What is it that you found there? I wanted very much to know really the nature, undisturbed nature. So, as soon as I arrived, I started to try to find a way to go to the Amazon. It was not very easy. EB: Because it’s very far away from Bogotá. It’s far away, and you need to have transportation. I said to the director of the institute: ‘I want to go to the Amazon. I have to study the vegetation, and if you want me to study the history of the vegetation, then I have to know it. I have to collect plants and pollen and so on.’ He said ‘oh that’s difficult. The minister of mines will never understand that.’ I said, ‘but well, I can make a study of the geology. Of course, I can look for minerals.’ He said that’s a good idea. They gave me permission to go. Then I was a month and a half or so in the Amazon. It was a fantastic experience because we really…at that time, we had no equipment. It was all very primitive. We ran out of food, and it started to rain, and we had nothing to protect us. So, we simply went there with two Indians and a canoe, and we were travelling everywhere. We went up the Quipu (sp?) areas. It’s sandstone hills. Of course, it was a fantastic experience and it was also the first study, the first geological study in that area. EB: But you said you had almost no equipment. How did you actually get the samples? We could get samples, of course. We had bags to put samples in, and we had old periodicals EB: newspapers newspapers to make the collection of the plants. So that was sufficient, but we had nothing to protect us. We had only hammocks. So, you slept at night between two trees in the jungle, and when it rained you got wet. EB: And you were often eaten alive by the mosquitos, I imagine. Yes, we had no mosquito nets, nothing. But that was quite an experience that you never forget. EB: And you became hooked then. Yes. From that time on, we started to make quite a lot of excursions all around the country. I worked here some eight years, I think, and had the opportunity really to travel a lot around and make studies in many parts of the country. EB: So not only in the Amazon but the rest of the country too. Yes, the rest of the country and the llanos and the Andean areas, so from sea level to the snow, as we say.

Professor van der Hammen eventually married a Colombian and their children were born there. In 1960, he and his family returned to the Netherlands. Professor van der Hammen took up positions, first at the University of Leiden and later at the University of Amsterdam. But he frequently returned to Colombia to carry out more research and eventually he headed up the first multidisciplinary study, involving geologists, botanists, biologists and other experts of what are known as “tropical Andean ecosystems.

The field work was done in the ‘80s. It started the first time, we worked was in ’77. We went to the Santa Marta massif. There was much interest in the rain, what was then the environmental ?? of the country. The Anthropological Institute had found some old Indian cities there in the area, and then we started there. We had a little house rented at the beach. Once a week we had a helicopter we could use. It was very difficult to enter the area. We had to enter several days walking and then in the mountains make a first helicopter place to be landing, heliport. And then the helicopter could land there, and more people could enter, and you could enter food and so on. From there started all  the work to make an inventory of the vegetation and so on and soils, etc. And then we had to go higher up. A group went 500 metres higher up and made another heliport. You came back then after three weeks or so in the mountain jungle, and then you came back to the little house and you just go in the sea. It was a nice experience. We had a laboratory there. So, the samples that came down were processed and measured. Later it was more mobile. We worked some four months in the Central Cordillera. There we had quite a lot of ?? We were able to make the installation of some 20 weather stations in the higher parts, above 2000 metres. Between 2000 and 5000 metres, there are practically no weather stations. And so, we, on both sides of the Cordillera, we could every 500 metres make an installation, and we were more or less able to get the information to two years. It was quite difficult because you had to move up all your equipment on wheelback, make an installation, and then you had to come back every month to get the data. So, somebody to get all the data needed 15 days, 2 weeks. So, it was quite complicated.

Sometimes we were in areas that were dominated by some type of guerrilla or so. Then you have to ask permission as in the ?? area, for instance. When we went there, we had first to talk to the people of the organisation, and they would give you the mules, etc. We went with them out. It was the rainy season in August, I think, in the south of Bogotá. Once we were in the middle of the area with the mules, they said well, it is raining very much. We want more money. Then I really was angry. I said ‘why?’ They said we are simple people and we need money. I said well, but you have land. You are landowners. I am only living from what I am paid. They understood this, but we had that type of problems. It’s something you had to arrange with the people. That were really very, very interesting times. Everybody learned a lot from it, and we are still publishing it. We have now five volumes, five thick volumes. The sixth volume on the Western Cordillera is now almost ready. I’ll bring that to the printer within a few weeks. And then there’s still one other, the Eastern Cordillera, that we have to finish because you can collect quite a lot of things in a few months and make many observations, but to work it out and everybody does his work takes a long time. EB: What was the goal of the project? Was it simply knowledge or was it something else? Well, knowledge but more or less an inventory of the natural environment of the country from all points of view. So, if you were thinking in development projects, you had to think how to use all these natural resources in a way that you don’t lose them. I think that is the central thing: how do you manage what you have. I think in that way with the whole team, we have made and we are making a contribution to that. That’s what we try to do now. We are just making a proposal with the national institutes, like the INDERENA, which is the national environmental institute, a proposal of how should the country be in vegetation cover and so on and in the way men use this so that we can really be sure that we will not lose biodiversity, that we will not lose water, that we will not lose the soils. That is in line a little bit with what in the Netherlands has been the principle ecological structure. So in line with the way of thinking how you should make a total view of the country, of protected areas, of biological corridors and the way you use the already changed environments, the anthropogenic influence, how can you manage that and how can you improve biodiversity in areas like here, for instance, the savannahs of Bogotá. Everything is grass and so if you make hedges and small elements of forests and small water elements like we have done here. We have here planted quite an area in forest and the richness in birds for instance has increased tremendously. Now we have some 50 species of birds here. We have a little wetlands I created where there is a lot of possibilities for frogs and so on to live. So, you can do a lot and that’s what we are proposing now for the whole country, so in the hope that this will be a basis for political decisions in this respect.

What we really have here in Colombia is a tremendous biodiversity. It’s one of the countries with the highest biodiversity in the world, and the protection of that is extremely important for the future. The number of species is very large, partly because we have two areas which have a very high biodiversity is the Amazon area and the Chocó area which are the lowland areas. These are very rich in species, and on the other hand, the Andes with a tremendous diversity of environment, different altitudes, different temperatures, different rainfall, which altogether make this immense biodiversity of the country. EB: Did you also discover new species as you were going along or new mineral formations? Well always you are collecting plants. Still you find new species. Even here, for instance, in the Bogotá area, where you think there are so many people around and there has been so much collection by botanists. Two years ago, we found a new tree species here north of Bogotá. Well, the question of geology is also very interesting. You may of course think find minerals or whatever, but on the other hand, the interesting thing is to know the history. What we have been studying much is the history of the vegetation, of the plants, how did they evolve in time, in the last, let’s say, 100 million years. What exactly happened? How did they come into being? You had a lot of movement of species. South America was for a very long time in history was isolated from other parts. So, after it separated from Africa 100,000 years ago, then the two continents went their own way and their own evolution. So, you have a very special flora in South America, tropical flora, but the Andes is a special case because part of the species of plants you have in the Andes, they evolved from the lowlands upwards, adapting species, new species to the new colder environment. But on the other hand, since some six million years ago, there was a connection between North and South America in the Panama area. The Panama isthmus was formed, and then you had an exchange of species, of plants and also of animals. In the higher parts of the Andes, a number of the genome of plants, some 50%, originally came from North America or the southern most part of South America. But they formed their own species here.

Most of the research carried out by Professor van der Hammen and his team was financed by the Dutch government and Tropenbos International, a Dutch-based group which carries out research on tropical forests.

The Netherlands has a history as a colonial entity. So there has been a lot of expertise in Indonesia, in the Caribbean area and so on. And we said we should not lose that expertise. That’s why there are still a lot of people working in the tropics in the Netherlands, and there are funds for that. So, I think that is a great advantage. Tropenbos was another initiative, more or less with the same idea that all this knowledge accumulated in the Netherlands in the past, it should not be lost, and we could help people in tropical countries with that. So, the knowledge present in the Netherlands could be used. At the same time, it was a collaboration with a lot of knowledge present in the tropical countries themselves, of course. So, this combination was very interesting, and in general in both cases, what we had was the collaboration of universities, of national universities, several other universities with the University of Amsterdam. We had a lot of interchange. I think that was very interesting. A lot of people from South America, especially Colombia also, made their PhD. in the University of Amsterdam. Students of the University of Amsterdam and other countries often could go to Colombia or to South America to make studies for their degrees. So, there was quite an intensive exchange at the university level. It was very productive, I think, not only in science, but also we had quite a lot of mixed marriages between people from South America, Colombia and from Europe, from the Netherlands. I really think sometimes, oh, what did I do? But I think most of these marriages are good marriages. EB: So, the Colombian soil is fertile in many ways. Yes, yes, that’s right.

EB: To what extent is the Colombian government taking these things into consideration in its planning? We have a very nice collaboration with my colleagues here. There is much goodwill to see what we can do. It is difficult, you know. Even if you see how things are in the Netherlands, how difficult it is to get a real principled ecological structure, for instance. It had to be something that has to go on for years to reach such a situation. Of course, it is much more difficult here. There is less money, and there is a lot of problems of insecurity in the field. So, the presence of the state is very feeble in many places still. The country is very large and difficult of communications. So those are additional problems, but there is no doubt that the government is very willing. They want to do something for the conservation of the biodiversity and environment. EB: The other problem, of course, is the drugs trade here in Colombia because large areas of land are being sprayed with chemicals to kill off the coca plants. A lot of trees, particularly in the Amazon region, are being cut to be able to plant coca. Yes, I think that’s a very sad story the whole thing. It’s not only Colombia, but in Colombia it’s very serious because besides that there was a tendency to get money out of that, the guerrilla now is protecting it. That, of course, makes it much more difficult. So, it’s not only a question of going to talk with the people and make them change for other products, but there is a military question in it. I don’t know how to resolve that. Well, we should have peace in the first place. The great damage is then by the people, in the first place the people who cut down forests, not only in the Amazon area, but also in the higher areas for the poppies. So that is the first terrible thing what’s happening to the country. And then if you are just using chemicals, you don’t know what’s worth. We don’t know exactly what to do. The only thing is that the whole politics in the world change because after all the motor behind that is the use of drugs. If there were nobody in the United States or in Europe who used drugs, there would be no problem. But that’s one of the bad things that has happened to the country. We hope that the future will bring better times.

EB: In the past 50 years, have you seen a major drop in biodiversity here in Colombia because of drugs or other issues? Yes. It’s a bit difficult to know exactly what happens. What we have seen in the past 50 years is the disappearance of much forest where we were working along the eastern slopes, for instance, of the cordillera here towards the llanos and towards the Amazon area. There was 50 years ago an extensive forest, and if you come back now where they have made a road, new roads, all the forest disappears. EB: Is it illegal logging? Yes, there is no control, no sufficient control, and the people they live from cutting down trees or even using the bark of certain trees for the preparation of leather. If you are poor, it is very difficult to think in the future. That’s one of the problems, I think. There are so many poor people in the country. They simply look around: what can I do just to live today and tomorrow. Another problem is the country also cannot solve these things alone. The developed world should more and more be involved in resolving these problems of poverty. EB: But you see quite the opposite, that the developed world is pulling back more and more and leaving the developing world on its own. Yes, it is very difficult to leave something that you have once gained. If you see how rich the European countries and the United States are, relatively rich. Young people can travel around everywhere. They have money for it, and then you say, well, how can we get a better… Do you say repartición EB: distribution of wealth yes, a better distribution of wealth, well, you’ll know the problem of the difference between the developed and the less developed world is one of the serious problems. Now the tendency is to maintain it and it gets worse.

Thomas van der Hammen's home
Thomas van der Hammen’s home

EB: You are in your 80’s now, right? Well, this year I’ll be 79. EB: 79, and you said so far that you have published five volumes as a result of the research you did in the 1980’s and 90’s, I assume. You’re working on the sixth volume now. When do you expect to finish? Well, I don’t know, but I hope to finish before I am 80 with these books at least. But there is still always to do. If the work you are doing in nature is something you do because you like to do it. I love nature and if you love nature, love every living being – be it plant or animal or man, of course – that is part of your life. And so, studying it, is moved by this love for nature. So, you can’t stop it. I’m very interested in other things also, sculpture for instance. I always wanted to have some time to do more about that. But up to now there hasn’t been. Here I am a little bit open to everybody who wants to ask something. So many people pass here from this house. They call me and they come and we talk. I help students and I still work in the university a little bit in the PhD. programme in biology. They ask me to help there and the international university. EB: Here in Bogotá. Yeah, but also in the other universities and in the national institutes. It’s nice. So I feel I’m still useful in some way.

EB: Does Colombia still exert the same type of fascination on you as it did 50 years ago? Yes. It is so diverse. It is so beautiful. It is one of the most beautiful countries, most diverse and beautiful countries in the world, I think. There are so many different things. It’s all ecological, environmentally it is so different. You have the driest spots in the world and the wettest spots in the world. You have places where you have more than 10 metres of rainfall and other places where there are only 100 millimetres. All differences in altitude between 0 and almost 6000 metres. That gives you a marvellous ecological laboratory. The fascination is still there. What is a pity is that you can’t travel anymore because of the security situation of the guerrilla activities and so on. That’s a pity. The problem for the universities and the students, they can’t make the discussions they made in other times or the biologists and geologists. You have to organise that nearby you are in the places where you still know there is no problem. EB: It’s a great pity because you speak of this country almost as paradise on earth. Yes, that’s right. But I hope that I can still live sufficiently time to see better times than we have now. EB: And this is where you plan to end your days. Yes, that’s the idea. We have always said that we want to pass the last part of our life here. I have so many memories and work here.

Chapel on Dr. van der Hammen's property
Chapel on Dr. van der Hammen’s property

I have not forgotten the Netherlands. My first 26 years or so of life and later again in the university, but especially the time between 12 and 26 years was a very productive time in the sense of knowledge, of nature. Also, in the Netherlands we had this youth organisation, the NJN, the Nederlands Jeugdbond voor Natuurstudie EB: The Netherlands Youth Federation for the Study of Nature Yes, I was a member of that, and that was a fantastic environment, incredibly from many points of view. You learned a lot and that left fantastic memories of camps and so on. I always think back on that. The North Sea for me, the beaches and dunes are some part of your life, when you were young, and I still want to go there, walk along these enormous long beaches without nobody to see and the North Sea islands. And Limburg, we had a lot of excursions as students, two weeks or three weeks of field work with a group of students in biology or ?? or both and soils, and try to give them this idea of multidisciplinary approach to the reality of nature. There’s a lot of good memories also there of people, young people. I like to go with students, young people, in the field. I still do that when I am able. It’s so nice to see the interest of young people. I was recently at the university in Manizales, and the university of Caldas asked me to give a conference,etc. after they had what they call the conservatory with the students, they were asking and fantastic. And the same I had in Armenia. There again we had made a meeting with a lot of young people from colleges and everyone most interesting. It is so nice to see the future, to see how the interest in all this, in the environment has grown quite a lot in the last 10, 15 years. That gives hope for the future. All these young people are interested and starting to know about it. So, that’s the future.

Professor Thomas van der Hammen in conversation with Eric Beauchemin. “Under Foreign Skies” is a Radio Netherlands’ presentation.

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