In 1976, a paper appeared in the scientific journal Flora, authored by University of St Andrews botanist Peter Gibbs¹ (now retired), on the breeding system of a tuber crop, oca (Oxalis tuberosa), that is grown by farmers throughout the Andes of Peru and Bolivia.
Like a number of Oxalis species, oca has a particular floral morphology known as heterostyly that promotes outcrossing between different plants. In his 1877 The Different Forms of Flowers on Plants of the Same Species, Charles Darwin had illustrated (in Fig. 11) the particular situation of tristyly in ‘Oxalis speciosa‘, the same floral morphology that is found in oca. In this illustration taken from Darwin’s publication, the ‘legitimate’ pollinations are shown; stigmas can only receive pollen from stamens at the same level in another flower.
Anyway, to cut a long story short, Peter had visited Peru in early 1974 (hard to believe that it’s 45 years ago), made collections of oca from a number of localities, particularly one village, Cuyo Cuyo, in the Department of Puno in the south of Peru (just north of Lake Titicaca), and then studied the breeding system of the oca varieties that he’d collected. His 1976 paper in Flora emanated from that field trip.
But there’s more to that story (and publication) than meets the eye. It was also tied up with the research I was carrying out on potatoes in the Peruvian Andes at that time. Peter and I made that field trip together, spending at least three weeks on the road, before flying back to Lima from Cuzco.
I don’t recall precisely when I first met Peter. We were obviously in touch when planning the trip south, but I simply can’t remember whether, during 1973, Peter had passed through Lima where I was working at the International Potato Center (CIP) in La Molina since January that year, or he had contacted CIP’s Director General Richard Sawyer asking if the center could provide logistical support and the DG had passed that request on to me. Whatever the course of events, Peter and I came to an agreement to make a field trip together to the south of Peru.
This is the route of more than 2000 km that we took.
While working as an Associate Taxonomist at CIP I was also registered for a PhD in potato biosystematics (under potato expert Professor Jack Hawkes at The University of Birmingham) which I was expected to complete by 1975. My work, studying the breeding relationships of potato varieties with different chromosome numbers was similar, in some respects, to that Peter envisaged with oca.
I’d been looking for suitable field locations where it might be possible to study the dynamics of potato cultivation in an ‘unspoiled’ area where mostly traditional potato varieties were cultivated rather than varieties bred and released on the market in recent years. At the back end of 1973 I made a short visit to Puno on the shore of Lake Titicaca to explore several possible field sites. Then, Peter proposed we visit the remote village of Cuyo Cuyo, around 250 km north of Puno. He’d come across a paper (either one by AW Hill in 1939 or another by WH Hodge in 1951 – both are cited by Peter in his Flora paper) that described widespread oca cultivation at Cuyo Cuyo on a series of ancient terraces, but also of potato varieties. I wasn’t sure if this was the location I was looking for, but agreed that we could explore Cuyo Cuyo first before heading north towards Cuzco in search of other likely sites.
Our journey south to Puno took at least three days if memory serves me correctly. Our trusty chariot was a short wheelbase Land Rover, with a canvas hood.
Not the most secure vehicle if you have to park up overnight in an unprotected lot. Nor the most comfortable; very sturdy suspension. But an excellent vehicle otherwise for ‘driving’ out of tricky situations.
We headed south on the Panamericana Sur, stopping at Ica or Nazca on the first night south of Lima, then on to Arequipa on the second day.
The Panamericana hugs the coast through the southern desert, crossing river valleys that flow down from the Andes to meet the Pacific Ocean. Along these, and in the area of Camana (where the road heads inland to Arequipa) quite a lot of rice is grown.
From Arequipa it must have taken another day to travel to Puno across the altiplano.
We then had another night to recoup in Puno, enjoying a comfortable bed, some good food, and perhaps one too many algarrobina cocktails (made from pisco) that Peter had taken a shine to.
Along the shore of Lake Titicaca near Puno
It took a day to travel to Cuyo Cuyo, across the altiplano (>4000 masl), fording rivers, and then, as we approached the village from the south, dropping into a steep-sided valley, the Sandia Gorge.
We hit a cloud layer, obscuring views of the valley, but also coming across a landslide that had to be cleared before we could make progress.
Once past that barrier, the cloud cleared and we began to see something of the majesty of the Cuyo Cuyo valley, with the steep valley sides covered in ancient terraces that, as we discovered over the next few days, were still be farmed communally as they had been for generations apparently. On the descent into Cuyo Cuyo, the banks alongside the road were also covered in masses of a beautiful begonia (Begonia clarkei Hook.) with large white flowers about 3-4 inches in diameter.
Where to stay? There was no hotel or pensión in Cuyo Cuyo. We did however have some camping gear with us such as camp beds, sleeping bags and the like. Plus all our other equipment for collecting (and drying) herbarium samples, and flowers and flower buds for pollen and chromosome studies.
After some enquiries we met Sr Justo Salas Rubín (who was, if I remember correctly, the local postmaster – seen with Peter below) who gave us space in one of the rooms of his home (the ‘post office’?) to set up ‘camp’. We also soon became quite a curiosity for the local children (and some animal friends as well).
I was not disappointed that we chose Cuyo Cuyo first. It was an extraordinary location where we could interact with potato and oca farmers who grew a wide range of varieties, and who were open to collaborate with us. Since that visit in 1974 several other botanists (and anthropologists) have made field studies at Cuyo Cuyo on the agricultural terraces that I described here.
While Peter set about collecting samples in the many oca fields (mainly beside the river on the valley floor), I set off up the terraces to study a couple of fields for their varietal composition, the ploidy (or chromosome number) of these varieties, and the factors that led farmers to accept or reject varieties. I was interested to see how triploid varieties (sterile forms with 36 chromosomes that can only be formed following hybridization between varieties with 48 and 24 chromosomes) could enter farmer systems, and at what frequency.
I also looked at the methods used to cultivate potatoes, and the tools used.²
On the left is a foot plough, about 4 feet in length, known in Cuyo Cuyo as a ‘huire’ (most often ‘chaqui taccla’ in other parts of Peru). Its component parts are: A. ‘calzada’ that rests on the shoulder; B. ‘huiso’ or hand grip; C. ‘lazo’ or leather binding fastening the parts together; D. ‘taquillpo’ or foot rest; and E. the ‘reja’ or blade. On the right is a hand tool used for harvesting potatoes (and presumably oca as well) called the ‘lawccana’, as well as other cultivations during the growing season. Its component parts are: A. the ‘ccalo’ or handle; B. the ‘lazo’, a leather thong holding the blade C. or ‘chonta’ on to the handle.
My paper on potatoes at Cuyo Cuyo was finally published in 1980 in the journal Euphytica. And that’s a tale in itself.³
Peter was keen to make herbarium sheets of many of the varieties he’d collected. We set up a dryer in the house where we were staying. But there was a problem. Most of the samples were pretty wet to begin with, as we experienced intermittent rain during our stay in Cuyo Cuyo. Oca stems are very fleshy, and despite our best efforts, they just didn’t dry out. Even when we got them back to Lima, and Peter prepared them for shipping back to St Andrews, many of the samples were still showing signs of life.
Indeed, after he returned to Scotland, Peter was able to take cuttings from his herbarium samples and grow plants to maturity in the glasshouse, thus continuing his studies there.
After three or four days in Cuyo Cuyo, we retraced our steps to Puno, then headed north towards Cuzco and further study sites near Chinchero.
At these, I was particularly interested in taking flower bud samples from different potato fields. In the area we chose, farmers grew a combination of bred varieties for sale in the local markets of Cuzco and, around their homes, native varieties for home consumption. In this photo, large plantings of commercial varieties stretch into the distance. Around the homes in the foreground, in walled gardens, farmers grew their native varieties.
As I was busy looking at different varieties, these two women came by, and one sat down to breastfeed her baby. They are wearing the traditional dress of that region of Cuzco.
On another day we set out to study potato (and oca) fields a little more remote, so had to hire horses to reach our destination.
Field work complete, Peter and I spent a couple of days resting up in Cuzco before flying back to Lima. We left the Land Rover there for one of my colleagues Zósimo Huamán to pick up, as he planned to undertake some fieldwork as well before driving back to Lima.
During the couple of days in Cuzco we paid a call on Prof. César Vargas, a renowned Peruvian botanist (and close friend of my PhD supervisor Jack Hawkes), who I’d met once before in January 1973 not long after I arrived in Peru. Prof Vargas’s daughter Martha studied for her MSc degree in botany at the University of St Andrews.
L to R: my wife Steph, Peter, and Martha Vargas
All in all, we had a successful field trip to the south of Peru. It’s hard to believe it all took place 45 years ago next month. But it remains, in my mind’s eye, quite a significant trip from the years I spent in Peru.
¹ Peter graduated in botany from the University of Liverpool, and completed his PhD in 1964 there under the supervision of Professor Vernon Heywood, who moved to the University of Reading to become head of that university’s Department of Botany a couple of years later. Peter and I had a lot to talk about, because in 1969-70, when I was an undergraduate at the University of Southampton, Vernon Heywood gave a series of 20 lectures on flowering plant taxonomy over 10 weeks to Southampton botanists, because Leslie Watson, Southampton’s taxonomy lecturer had moved to Australia. Vernon and I renewed our acquaintance some years later, in 1991, when he and I attended a genetic resources meeting at the Food and Agriculture Organization of the United Nations (FAO) in Rome just before I moved to the Philippines to join the International Rice Research Institute (IRRI).
² One interesting piece of information that didn’t make it into my thesis but which I remember clearly was the incidence of geophagy among some residents of Cuyo Cuyo. I was taken to a location where farmers would excavate small quantities of a hard clay, that would be ground to a powder and mixed with water to form a slurry or soft paste. They would then dip recently harvested boiled potatoes in the clay as this, apparently, would decrease the slightly ‘spicy’ flavor of some of the varieties. I’m not sure how widespread this behavior was, but it’s something that has stuck in my mind all these years. I think I once had photos but they are long lost, more’s the pity.
³ I completed my PhD in December 1975, and shortly afterwards moved to Costa Rica to continue working for CIP, in potato breeding and agronomy. I started to prepare three manuscripts from my thesis for publication in Euphytica. The first, on varietal diversity, was submitted in February 1977, and published later the same year. The second, on breeding relationships, was published in 1978, having been submitted in July 1977. The third, on the ethnobotany of potato cultivation in Cuyo Cuyo finally appeared in print in 1980, having been submitted to Euphytica in February 1979.
But Euphytica had not been the first choice for this third paper. I actually produced a manuscript for the journal Economic Botany, and it included more details of the cropping systems and varietal choices made by farmers. My paper was received by the journal and acknowledged, but then I heard nothing more, for months and months. Eventually I wrote to the editor asking about the status of my manuscript. And I received a very strange reply.
It seemed that the editor-in-chief had retired, and his replacement had found, on file, manuscripts that had been submitted up to 20 years earlier, but had never been published! I was asked how I wanted to proceed with my manuscript as there was no guarantee it would appear in print any time soon. But about the same time, I received a nice letter from the then editor of Euphytica, Dr AC Zeven, complimenting me on my PhD thesis (which he had read in the library at Wageningen University in the Netherlands) and encouraging me to publish my work on the ethnobotany of potatoes – if I hadn’t already done so. I withdrew my manuscript from Economic Botany, and after some reformatting to fit the Euphytica style, sent it to Dr Zeven. He requested some deletions of the more descriptive sections on ethnobotany, and published my paper in 1980.
One last thing: I also remember was the novel that Peter was reading throughout the trip. Watership Down by Richard Adams, first published in 1972, that went on to become a literary sensation. I did read it myself at some point, but whether I borrowed Peter’s copy immediately after the trip, or some time later, I don’t recall. I know I didn’t think it would become the phenomenon that it did. What do I know?
9 February 2023
Today I received the news that Peter passed away, at home in St Andrews, on 6 February. That would be almost 49 years to the day since we set out from Lima on our expedition to the south of Peru. Rest in peace, Peter.
A balanced diet . . . 