Seeds planted 300 years ago are helping us today (Irish Times Article)

16 March 2011

By Dick Ahlstrom:

Trinity College’s botany department is celebrating its tercentenary at a time when its collection is helping in the study of climate change

TRINITY COLLEGE Dublin is busy planting a new medicinal garden on campus, to help celebrate the 300th anniversary of the study of botany there.

And there is a fitting symmetry in doing so given the then provost and university fellows resolved, on June 25th, 1687, that the campus’s kitchen garden “should be made a physic garden at the charge of the college”, to provide suitable plant material for the teaching of medicine. This garden effectively marks the start of botany at Trinity, although only informally.

No one on campus has pinpointed where exactly that garden grew but 300 years ago this year, in 1711, Trinity appointed Henry Nicholson MD as its first botany lecturer.

The university has much to celebrate, given its long tradition of involvement in one of the most fundamental areas of science, says Prof Fraser Mitchell, associate professor and head of the Botany Department in the School of Natural Sciences at Trinity.

“Plant science is a fundamental building block. It is the system that traps energy from the sun to drive ecosystems,” he says.

The 300th celebrations (visit tcd.ie/botany/tercentenary) highlight the important contributions made by the department over the centuries, but also demonstrate the relevance of its work today.

Climate change and the effects on plants caused by rapidly rising carbon dioxide levels are a subject of intense study internationally. But the department and, more particularly its world famous plant collection or “herbarium”, holds 300,000 plant specimens, many of which were collected before greenhouse gas levels began to rise.

The herbarium has become an important international research tool because of the ongoing changes to our environment, says Prof Mitchell.

Plant specimens held there are used in the study of climate change; in areas such as world food production and to look at the extinction of plant species.

People are concerned about animal conservation, “but you can’t conserve them without conserving their ecosystems” (the plant-dominated habitats in which a species lives).

The collection has been built over centuries and the original plant material is there to be examined and studied.

“The herbarium is part of a big international network. It is something that is irreplaceable. It is like an ancient library; if you lose it you can’t get any of it back,” says Mitchell.

Its international importance is apparent in the hundreds of plant “type species” held there. These were new plant discoveries subsequently established to be unique and not part of other collections. These then become the international “type” against which all other similar finds are compared.

The Physic Garden planted in 1687 points up the importance of plants in providing medical treatments. A large fraction of the modern drugs we use were originally derived from plants.

It is not surprising then that the first three lecturers in the department, Henry Nicholson, William Stephens and Charles Chemys were all medical doctors and Stephens later moved to chemistry. Those three disciplines, botany, chemistry and medicine, are closely linked, Prof Mitchell says.

The current herbarium curator is Prof John Parnell, but the original curator and its founder was Thomas Coulter, who took the job in 1840. It began with his personal collection.

He was a highly successful early plant collector and he added to the herbarium during his time in office.

He was followed in 1844 by one of Trinity’s more famous botanists, William Henry Harvey. He explored the world for novel plants, adding 100,000 specimens to the herbarium from Australia, Africa, North America, and Asia.

He was a friend of Charles Darwin, who proposed natural selection as a driver for evolution. Darwin, when on his round-the-world-tour on board the HMS Beagle in the 1830s, sent back plant material and hand written notes to Harvey for analysis.

“The herbarium is one of our more remarkable resources,” says Dr Daniel Kelly, senior lecturer in botany at Trinity.

“A piece of [a plant] dried and preserved, able to last indefinitely, is the ultimate definition of a species.”

Image: Amphiroa Darwinii at the Botany Building in Trinity College Dublin, which was sent to Trinity by Charles Darwin while onboard the HMS Beagle in the 1830s. Photographer: Dara Mac Dónaill

© 2011 The Irish Times