The Living World / Environment
What Do You Know about the Life Histories of Wild Plants?
Masashi Ohara , Professor
Faculty of Environmental Earth Science / Graduate School of Environmental Science (Biological Sciences, School of Science Biology majors)
High school : Hokkaido Sapporo Nishi High School
Academic background : Hokkaido University Graduate School of Environmental Science
- Research areas
- Plant ecology, conservation ecology
- Research keywords
- Plants, ecology, evolution, life history, field, biodiversity
What prompted your research?
I was passionate about plants right from childhood. I learned the names of all the plants blooming in the hills and fields. However, when I was in high school, I had vague ideas about wanting to study plants, but my mind was still not set on any particular “This is what I want to do!” thing to study at university. I enrolled in Hokkaido University and joined the Faculty of Agriculture, where I focused on crop physiology, namely the relationship between potato sprouting and plant hormones, for my graduation thesis. Then, after graduation, I decided I wanted to do more research out in the field, and so I became a grad student at the Graduate School of Environmental Science, which had just been established, to study plant ecology. It was at this time that I encountered the research field of plant life histories. Life history research involves the study of how plants grow, flower and fruit in various outdoor environments. I had always loved plants, and I knew all their names and thought I knew all about them, so it came as a shock to me when I couldn’t even answer simple questions about, say, familiar roadside plants like dandelions and white clover, such as how exactly they grow until they start flowering, or how exactly they leave offspring. It was that shock that set me off on this path of research. I got into the research I’m doing now through my desire to solve the mystery of how plants, which can’t move by themselves once they put down roots into the soil, manage to evolve their life histories as part of the many different physical and biological environments around them.
Trillium camschatcense flowers (left), the emblem of Hokkaido University, and their life history (right) The stems of flowering individuals have three leaves, and the flowers themselves have three petals and sepals, but when they germinate from seeds, the plants spend several years with just one leaf. It takes them over ten years from germination until they finally flower.
What kind of research are you carrying out?
In my laboratory, we carry out both fieldwork and indoor genetic analysis experiments in our quest to shed light on the life histories of plants that have evolved in a diversity of environments.
Fieldwork: Looking at plants and picking them up and feeling them are fundamental to the study of plant biology. Our fieldwork involves getting out into forests, grasslands, highlands, wetlands and other habitats where the plants we are studying grow so as to observe, measure, and carry out experiments on them. Studying the various aspects of the environments in which wild plants grow, such as the environmental conditions of their habitats or the insects that carry pollen or seeds, is essential to understanding the life histories of plants. There are many biological phenomena that only become apparent through dogged perseverance, and so a lot of our research involves doing the same work each year for years on end.
Genetic analysis experiments: Genetic analysis experiments reveal things that we cannot hope to learn just through fieldwork, such as gene flow and the spread of clones through the pollen and seeds involved in reproduction, and the genetic diversity imparted to the population through them. Because wild plants grow in a variety of environments, species and populations contain genetic variation. For these experiments, we analyze enzyme protein amino acid sequences or DNA nucleotide sequences for mutants, using plants that we’ve collected in the field. Then we take the results of this genetic analysis back into the field to check their consistency with what we see on the ground there and develop an overall picture of the life histories of the plants we’re studying.
Fieldwork can be tough, but it’s also a lot of fun.
What do you plan to do next?
Since plants can’t move elsewhere of their own accord, the environments in which they find themselves are critical to their growth. As well as investigating the life histories of plants that adapt to and evolve in these diverse environments, I would like to apply the results of my research to helping to preserve the natural environment and biodiversity for posterity. And as someone who started off with a fondness for flowers and ended up becoming a botanist, I’m also eager to communicate the pleasures of such a life to the next generation.
(1) Masashi Ohara, The Life Histories and Reproductive Ecology of Plants (Shokubutsu no seikatsushi to hanshoku seitaigaku) Kaiyusha (2010)
(2) Masashi Ohara ed., The Natural History of Flowers (Hana no shizenshi) Hokkaido University Press (1999)