We are about to wrap up the interview in Just Jensen's office when he suddenly says:

'- I just need to say that one of the things that I think is important to say to the young people around here, is that after all, I started from a different background than the vast majority. I have only gone to school for seven years and have never attended a Danish university or similar. But even if you start somewhere else, it is quite possible to have an interesting research career. It's just a matter of seizing the opportunities that are available. That's what I've done. That, I think, is an important message.'

When Just was a child in the 1950s, it was not written anywhere that he was to become a researcher and pioneer in quantitative genetics and genome research. As the only boy of three siblings, the plan was rather that he would take over the parents' smallholding between Randers and Mariager, where he was born and raised. But a pivotal event changed everything.

'- My father died in 1960, when I was seven years old,' says Just. 'After that, my mother continued the farm for a few years, in the sense that my older sister, like me, was taken out of school after the seventh grade, and then came home and worked as farmhand on the farm. Back then you had to go to school for seven years, and then I was home and helped look after the farm for the next few years. I also have a younger sister, but no one believed that she would do the same as her older siblings, so the farm was sold when I was about 16 years old.'

Is it also at that time you started your agricultural education?

'- Yes, I was 16 when I moved away from home for the first time, when I was at boarding school [efterskole] for half a year near Aarhus. Back then, the agricultural education consisted of working on various farms. And I did that from the time I was 16 until I was 21-22 years old. I did my military service from 1972 to 1973, I think it was. After that I attended Bygholm Landbrugsskole, quite shortly after I had been in the military. I was initially at agricultural school for just under a year,' says Just.

So, your military service came in between?

'- Yes, there was a break of a year, when you did your military duty. Back then, the agricultural education consisted of nine months, during which you attended an agricultural school. And when I finished that, all the people I went to school with had to go home and buy a farm or take over their parents' farm. But we didn't have a farm anymore and I had no money, so for me that didn't happen. So I took an extra year at Vejlby Agricultural School in Aarhus, and became an agricultural technician. It was a year on top of the agricultural education,' explains Just. '- At Vejlby Landbrugsskole we had a teacher, Gregers Ørnsvig, who to a great extent started my interest in breeding and genetics.'

In 1976, an opportunity came to Just Jensen, which he seized.

At the Land Economic Research Laboratory [Landøkonomisk Forsøgslaboratorium /ed.], which later came to be called the State Livestock Laboratory [Statens Husdyrbrugsforsøg /ed.] in Copenhagen, they needed an assistant, and the researchers there knew some of the teachers at Vejlby Agricultural School. Just must have made a name for himself at the agricultural school, because he was one of three chosen to be employed as assistants at the Land Economic Research Laboratory.

Was that why you chose that path instead of farming?

'- It was a bit of luck, I think. We were three who got hired, the other two didn’t stay for long. After a year or so, they found out that they wanted to do something else. But I stuck around,' says Just.

So, you moved from Jutland to Copenhagen?

'- Yes. I had my family in Aarhus. At that time we lived in Viby. So, I first moved there myself for a few months and then the rest of the family moved. We lived in the Brøndbyerne in Copenhagen from 1976 and until 1982, when the institution in Foulum was built. We were actually four employees who were the first to move to Foulum and moved in at the same time. That included me and Per Madsen, who is also still employed at QGG. The other two have long since stopped,' says Just.

In 1986, another opportunity arose, which Just Jensen was not slow to seize. Once again because he had made himself noticed. He was invited to Michigan State University to do a PhD thesis.

‘- So, the background is that I worked in a small research group, where as an assistant I had to help make statistical calculations,’ Just remembers. ‘- Back then, you had an assistant to do calculations on the computer. Over on the other side of the street, on the 4th floor, there was a punch card room where you made punch cards for the computer. I did that for a few years, following instructions from the researchers I worked for. Then gradually it happened that I was the one who knew the statistical methods. I was the one who knew what they were doing. And in general, I probably knew more about them than the researchers who actually had to use the results. So that meant that my boss at the time, whose name was Bernt Bech Andersen, got me onto an inter-Nordic course, which at the time ran in shifts in the Nordic countries with one course a year. I attended such a course held in Uppsala, Sweden. The lecturer there was Ivan Mao from Michigan State University, and he heard someone in the back of the classroom who couldn't quite keep his mouth shut,' Just laughs. '- But he invited me over to Michigan State to do a PhD based on the experience I had at the time.'

So, the whole family, Just, his wife and two daughters went to the US for three years, and came back to Research Center Foulum (AU Viborg) when the PhD thesis was defended.

Was a PhD also three years back then? 

'- In the US it’s a little more flexible. You start there when you're accepted, and then you finish when you're done with your thesis. It can vary quite a lot. But I got funding from Denmark [supported by the Agricultural and Veterinary Research Council, /ed.], so in Denmark it was three years, and I did it pretty much on time,' says Just.

Later in the interview, when we are about to end, he returns to his PhD time in the USA and emphasizes once again that even if you come from a modest background, seizing opportunities when they present themselves can make a world of difference: 

'- In the USA, you can be admitted to a PhD programme, even if you do not have a traditional academic background. That's quite difficult here in Denmark. But in Michigan, that's not a problem. You are evaluated on who you are. And if you think you can handle it, you will be accepted,' says Just and gives an example:

 ’- Their argument, without comparison by the way, was that if Einstein had come by, he also had an unconventional background... If he comes and says he wants to do a PhD, would we say no? No, maybe we wouldn’t. So that's why they said yes to me. At least that’s what they said then.'

Just goes on to say that the year he graduated as a PhD, there were about 1,000 others who graduated the same year, and he was in the top 1 percent on the scale that Michigan State used at the time.

You finished in the top-1?

'- Yes,' Just says with a smile.

Wow! But do you think it would be tougher today?

'- It probably would. We have a lot of very talented students. But the American system is more flexible than the system we have in Denmark'.

Yes, because they are pretty strict here…

'- Yes, but one of the things I have taken with me in my management career, which we haven't talked about so much, has been to try to help where there are talents that need to be helped. If you can do any of this, then it is more important to look at the person than it is to look at their papers. And I have tried to do that as much as possible. To learn from my own experience.'

Why did you choose genetics and genome research as research area? Was it from the start, or was it luck, more or less? 

'- Well, even before I went to the USA, it was completely obvious. At that time, I was already extremely absorbed by genetic research and wanted to find out how genetics work. That has largely been a driver. There was a curiosity about how these things work. The stay in Michigan also helped a lot because I got some extra education and got a stronger professional foundation to stand on,' Just says.

Someone who has experienced Just Jensen's curiosity and scope of interest up close is senior researcher at QGG, Per Madsen. The two have worked together since Just was employed at the State Livestock Laboratory, where Per Madsen had already been employed for a year and a half [Per Madsen celebrated his 50th anniversary in 2024 /ed.]

Per, you told me earlier that Just can multitask to some extent. What do you mean by that? 

'- Well, it lies in the fact that we had a visit from Robin Thompson, who was professor in Edinburgh at the time. And it was he who in his time found out how to create what is called Restricted Maximum Likelihood (REML) for the Estimation of Variance Components. He was visiting, but at the same time Daniel Gianola from Madison was also visiting,' Per says.

'- Robin Thompson’s work is based on traditional statistics, while Daniel Gianola is a Bayesian statistician. These are two very different ways of approaching things. So, while they were visiting at the same time, Just was both involved in developing and implementing AI-REML, and also programming a Gibbs sampler together with "The Daniels", that is, Daniel Gianola and then Daniel Sorensen from our department,' explains Per. 

'- So that's why I’m saying he multitasks, because he spent half the day with Robin Thompson and me, developing and programming AI-REML. And then the other half of the time he was with Daniel Gianola and Daniel Sorensen making a Gibbs sampler.'

Were these methods that came together at some point, or are they still two different ways?

'- Well, these are two different ways of attacking the same problem. In principle, if you have enough data, it gives very similar results, but it’s two very different ways of getting there,' Per elaborates. 

'- And when we have been to conferences around the world, there has always been a discussion between Robin Thompson and Daniel Gianola. It's kind of been a lot of fun to hear, because they don't agree. And what we did was presented at the world congress in Guelph in 1994. But that has led to us also later having a Gibbs sampler made, so that is also in the DMU package. That's the kind of thing Just did.'

'- But otherwise, Just has always had a knack for devising very complex models that we had to be able to handle,' Per continues. 

'- And then he has always said that we must be able to implement this or that. And then he would tell me a bit about what this or that model was supposed to be able to do, and then I have tried to add a new facility in the DMU package. However, it has often turned out that it is a little more complicated than he had thought. So, it could easily take a few days before the new facility was added. As I said, he has been really good at developing models, but he hasn't always thoroughly considered how complicated it would be to get it done, when at the same time we had to be able to keep running the old models,' Per says. '- It could happen that you could make some twists and turns through the program so that you could make the new model, but then it couldn't run some of the others, so we always had to test that it didn't destroy any of what we already did, and then get new things in. So, he has generated a lot of work for me,' Per laughs with a twinkle.

In 1994, another opportunity arose for Just, when he became research leader at the Section for Livestock Breeding and Experimental Genetics, Department for Livestock Breeding and Genetics at Denmark's Agricultural Research, as the institution in Foulum was called at that time. In a report drawn up by an international evaluation panel, it was highlighted that the group, which developed from a staff of 9 scientific staff including 3 PhD students in 1995 to 20 scientific staff including 7 PhD students at the time of the evaluation, was a 'well-functioning group with a high professional level' under Just Jensen's leadership. 

The years as a research leader at the Department of Livestock Breeding and Genetics and a member of the department's management group gave Just valuable experience in collaboration, organization and meeting management, which he supplemented with courses in project management, organization, personal development, management and leadership development.

After a research stay at the University of Wisconsin, Madison (USA) and the University of Guelph, Ontario (Canada) in 2000-2001, another career development opportunity appeared. The position as head of research at the Department of Livestock Breeding and Genetics was advertised, and Just applied for, and got, the position, which he held from 2002 to 2005, as a successor to his former boss, Bernt Bech Andersen.

In 2005, Just took another step up the career ladder when he took over as managing director of what was then called Agricultural Research Denmark [Danmarks JordbrugsForskning], which in a later restructuring came to be called the Faculty of Agricultural Sciences.

And that accession was actually the reason for the whole story of the bust of N.J. Fjord, says Per Madsen: 

'- Just brought department secretary Jette Laursen to the management offices, and Jette Laursen believed she had ownership rights over the N.J. Fjord statue. Some of us didn't quite agree with that,' Per jokes. 

You can read the story about N.J. Fjord here.

In 2007-2011, Just Jensen was dean at the Faculty of Agricultural Sciences, after the merger between Agricultural Research Denmark and Aarhus University. 

Just writes in his CV that his long list of employment has largely been within research management and has given him considerable management experience. '- For me, management has always been based on dialogue as a basis for a modern management style. An important element here has always been solid support for both internal and external collaboration,' he writes further.

What would you say characterizes your career? Is it research management?

'- There are two characteristics. The first is curiosity, which I touched on before. The second thing is that if you look at the job titles I've had, I've had more than 10 different job titles. And they never lasted very long. Usually I've had a position for 3-6-7 years and then I've moved on to something else. I have experienced changes at regular intervals. I have held my current professorship for a good ten years, so that is the position I have held for the longest time.'

So, it’s not so much research management that characterizes you. It's more curiosity?

'- No, it's a mixture,' says Just, and continues in the same breath: 

’ - because with the fact that I had this long management experience as head of research, director and dean, so right from the start, when I came back to research, I carried out all the tasks myself. But pretty quickly I got a group of 10-12 people, approximately 5 PhD students and 5 postdocs who carried out the actual research. When you have to guide so many people, you don't do anything yourself, because then you spend all your time supporting them, talking to them, as well as managing and leading the projects they are a part of. So, it’s a combination of management and professionalism in a group of colleagues and a portfolio of projects. But the good thing about having 10 good colleagues who each work on their own project is that I learn 10 times as much as they do, because I have to understand everything they do. So, it's a much faster way to learn new things. And it appeals to my innate laziness that I don't have to do everything myself,' Just laughs. ’- and ensuring continued funding for such a research group is also quite a significant task.’

'- Just has been supervisor for an incredible number of people, both master's and PhD students as well as postdocs,' says Per Madsen, '- and he has been part of many working groups, where he has drafted the ideas, and then had some work distributed to others. He has been good at that. And he has also been good at, when they come up with a draft for a paper or something like that, really go through it. "That, it's not clear enough, it's not quite how it's done". He has been very good at giving comments on papers and reports and getting them streamlined so that they can be published.'

Another colleague who has greatly appreciated Just as a colleague and supervisor is Xiangyu Guo, who in 2016 defended her PhD thesis, which was carried out at the Center for Quantitative Genetics and Genome Studies (later QGG) under the Department of Molecular Biology and Genetics in collaboration with China Agricultural University. 

'- Even though it's been 11 years,' she recalls, '- I can still very clearly remember the Friday morning when we had Friday bread. I mentioned to Just that I was about to complete my PhD thesis, and asked him casually if there might be an opportunity for a postdoctoral position,' she says and continues:

'- Honestly, I had expected a short or polite answer, but to my great surprise, Just took my question seriously and mentioned several projects that I could potentially be involved in. And not long after that, I had the opportunity to work with Just in a postdoctoral position.'

'- Because I had to transition from animal breeding to plant breeding, there was a lot to learn, but Just was always patient and tireless, explaining things while filling the whiteboard in his office with text and drawings to help me understand and solve a given problem,' says Xiangyu.

Through all their talks, Xiangyu also experienced Just's passion for research, and often, even though his calendar was full of meetings, he had time to talk to her about life and how she was doing.

'- I really felt that Just didn't just see me as a postdoc, but that he also taught me how to build my future career. To me, he was not just a supervisor, he was more of a father figure,' Xiangyu concludes.

Just has around 430 publications on his CV from 1980 until today, and more are added on a regular basis. The list testifies to an extensive collaboration with Danish and international researchers in virtually all corners of his research area.

After 5 years as dean, Just returned to research in 2011, and on that occasion, he was appointed professor.

How come you then chose to work with plant genetics?

'- When I quit as dean, first of all I received a grant of DKK 10 million from the rector to restart my research. So, there was like a free space to start something new. One of the first things that happened was that I was contacted by some plant breeding companies, who had heard about some new technologies that we had used in livestock up until then, and which they could see a potential in using in the plant area as well. The problem in the plant area was that they had focused a lot on molecular genetics, individual genes, whereas we look at all genes at the same time using mathematical models. And my prejudice is somewhat that looking at individual genes basically doesn't work for many important traits, whereas using the mathematical models and looking at everything at the same time works better,’ Just explains. 

‘- And that’s what we demonstrated, first on grasses and then on other species. We have in turn done projects on all the most important Danish plant species, and shown that the method ensures a more effective breeding program than the classical methods. And the reason we were asked was because we had the skills to use that type of math and models. But the entire plant world had focused primarily on molecular genetics. And they were really, really good molecular geneticists, but generally bad at quantitative genetics, that is, the general model-oriented genetics that we primarily use. And the few left who knew that technique had either retired or died. So that's why we were asked if we wanted to go into a project in that direction. So, we first started on grasses, and since then it has developed to the point where we had a whole group of between 10 and 15 people working on plants. At first it was in Foulum, but later we moved to the Campus in Aarhus and now work together with plant geneticists from Flakkebjerg,' he elaborates.

So now it's been 15 years and it's evolved into a cornerstone of QGG?

'- Yes, but it has a much greater professional breadth now. In the beginning, when we were in Foulum, we were not as such a plant group, we were more part of quantitative genetics, and then we collaborated with various plant researchers and plant breeding companies. We now have a close collaboration with plant research, which is partly at the Flakkebjerg Research Center. In the future, we will undoubtedly see a much closer collaboration between quantitative, i.e. mathematical, and molecular genetics,' he says.

If you have to put into words yourself what has been your greatest contribution to the research field, what has it then been?

'- It has obviously been some contributions that we especially made during my PhD regarding mathematical methods to investigate genetic variation. Methods that are still used a lot. And the other major contribution has been to move modern quantitative genetics into the plant world. These are the two places where I have contributed the most,' he says.

'- The first one was very mathematical and very direct science-oriented. The second, the transfer of an area of ​​knowledge, of course requires a solid research background, but to a large extent also a management background, in order to contribute to the transfer of knowledge together with research colleagues and cooperation with employees in commercial companies.'

If we are to talk a bit about the person behind the researcher, you have told me that you grew up in the countryside and your parents had a smallholding. You also said that you are married and you have two daughters. What do you do in your spare time?

'- It is divided in two, understood in the way that before, especially the period when I was head of research, director and dean, I did not have much free time, but I did take a vacation once in a while. I had a fixed principle of arriving at work at 8 am each day, and then drive home at a more or less normal time to take an afternoon break. After that I worked most days until 9 pm, but not longer. This means that I spent quite a lot of time working, because it’s not something that comes by itself. And therefore, leisure was a relatively rare concept for me. And these things applied to pretty much every day of the week. So, there is no doubt that, due to the time spent, my hourly wage has, among other things, been far too low,' Just laughs.

Also in the weekend?

'- Yes. Of course, there has been free time in between, but there is no doubt that my family's patience has been greatly strained. Therefore, it has been important for me, when I started to scale back on my working time, as I did four years ago, to create more time for other interests. And I spend that time, among other things, being a beekeeper. So, I spend time taking care of my bees, of course, and I'm active in the local beekeepers' association. I’m on the board of our local cultural and sports centre, and I’m active in an association that contributes to better access to nature and other things, such as nature renovation and nature restoration. And then my wife and I have started spending a lot of time on hikes too, both in Denmark and internationally. In general, we are very nature-oriented,' Just explains.

Where do you hike?

'-My wife has always been very interested in traveling and hiking, so we have also been on hiking trips in, for example, Australia, South Africa, Kilimanjaro, Korea, China, Peru, Brazil, Costa Rica, Canada and many other places. But now it's mostly in Denmark, and then every year we take a few trips a little further away, typically to Spain, or at least Southern Europe. In everyday life, we typically go on shorter trips a few times each week.'

Tell us about your bees. How many hives do you have?

'- Right now, I have seven hives, which is about twice as many as I would like. Actually, I would like to have three or four, but they do breed, so they’re kind of multiplying. I’ve been lucky to make them survive. There are always other beekeepers who have too few bees in the spring, as it is generally during the winter period that there can be some mortality. If there are any beekeepers who are short of bee colonies, they will get or buy some from me.'

Do you harvest the honey yourself? How many jars do you get?

'- It varies a lot, because if I sell a bee family, there won't be that many jars out of it. But last year we made, I can't remember exactly, it's about 200 kg, so it's approximately 450 jars. Some of it I sell, some of it I give away as hostess gifts or the like, and I also have a stall by the road. Finally, I have a collaboration with a couple of farm shops that sell my honey.'

'- I think it's fun to look after the bees and then harvest the honey,' he continues. '- But the rest of it with putting it on jars and going out to market it, I don't think that's so much fun. So, if I were to have more bees, I should do more. But I actually think it's more fun to make a few extra beehives and extra bee families.'

When I ask Per Madsen if there are any stories and anecdotes to tell about Just from their 50-year collaboration, he hesitates a bit. 

But when he calls you a grumpy old man, you call him the same?

'- Yes. That's right,' Per laughs.

'- When my daughter was doing her master's in Foulum, she had heard that there were many who thought that there were two grumpy old men in the department, and they did not dare to come to. And she couldn't understand that, because as a 1½-year-old she sat on Just's lap. That was when we did that AI-REML thing, they came for dinner at our place in the evening. So, these grumpy old men, she wasn't so afraid of them. Because, as she said, "I sat on Just's lap when I was 1½ years old, and the other one is my dad". So that's why, but apparently someone has thought that we might be a little difficult to approach.'

When I spoke to Just a year and a half ago on the occasion of Per's 50th work anniversary, I got the story about Per, who, after a festive conference dinner in Armidale (Australia), missed the flight to Sydney and on to Auckland (New Zealand), where he and Just were going to the next conference. 

It turns out that Just has done just about the same stunt.

Per tells the story: '- Together with Gert Aamand from NAV/SEGES we were going to a farewell seminar for Esa Mäntysaari in Jokioinen, Finland. Just found a nice connection from Aarhus Airport via Arlanda to Helsinki. When it was announced that the gate was open, we had not yet seen Just, but we boarded the plane. When we took off, we still hadn't seen Just, and when we landed at Arlanda, I got a text message in which Just explained that he had been sitting and waiting at the airport, where it was clearly marked that no calls are made to the gate. Just came to the gate only when it was closed. And then we had some problems because a car was booked for us in Helsinki. We had to drive up to LUKE in Jokioinen, and the car was rented in Just's name. It couldn't just be transferred to me, so I had to rent a car all over again. I don't know if he had to pay for that car, I've never asked.'

So Just did the same stunt as you did in Armidale?

'- Yes,' Per laughs. '- But eventually I arrived at the destination, Just didn't.'