By Helen Roberts
For the past three years, the University of Bristol Botanic Garden has hosted Fascination of Plants Day. The event is part of a much larger initiative launched under the umbrella of the European Plant Science Organisation (EPSO). The goal of the day is to get people interested in plants and share the significance of plant science in both the social and environmental arenas.
In 2013, the inaugural year of the event, a total of 689 institutions in 54 countries opened their doors to the public and talked about the wonder of plants. The activities carried out by each institution were extremely varied, but they were united in their celebration of plants. Here at the University of Bristol Botanic Garden, there was a focus on plant classification. In Russia, huge numbers of people attended guided tours on Siberian flora. In Nigeria, focus groups discussed possible partnerships between farmers, processors and scientists. In Norway, workshops were held for children to teach them how to grow their own vegetable gardens.
This year, Fascination of Plants Day was held on Sunday, 17th May. Students at the University of Bristol were in the garden discussing plant classification and research in the plants sciences. I met two final-year undergraduate students, Joshua Valverde and Will Perry, who were on hand discussing different topics within the plant sciences and fielding questions from the public.
What’s in a name?
Many queries related to binomial nomenclature or plant naming. In biology, the name of a plant (and indeed all living things) is divided into two parts; the first name – the genus – defines a group that comes from a common ancestor and have some common features and the second part – the species – groups together organisms that can interbreed and produce fertile offspring. Together, the genus and species forms the Latin name. Poster information compiled by Joshua explained the history of plant classification.
Joshua explained how plant classification changed over the centuries.
“To begin with, Theophrastus, a Greek philosopher, was one of the first to document and characterise plants by their morphological features. After that, plants were classified according to their medicinal use. And then long and unwieldy Latin names were used based on the morphology of the particular plant. It wasn’t until the mid-1700s that Carl Linnaeus introduced the binominal system.”
Of course, taxonomists don’t always agree on which groupings some species belong to, nor on where groups should be placed in the broader contexts of plant evolution. Classification of plants originally relied on finding similarities in form and structure (morphology) between plants. “This was subject to error though because unrelated species may evolve similar structures as a result of living in similar habitats or in response to some other adaptive need. This is called convergent evolution,” explained Joshua.
However, molecular methods have helped resolve some of these disputes.
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| Gnetum gnemon, a member of the order Gnetales. Photo courtesy of gbohne on Flickr CC. |
“Morphological data suggested that the order Gnetales [what we now consider a group of ‘advanced’ conifers] was the closest living relative to the first flowering plant,” explained Joshua. “After molecular analyses of various genes, however, it is now thought that Amborella trichopoda [a shrub native to New Caledonia] is the closest living relative to the first flowering plant. Water lilies also seem to be quite an ancient lineage.”
Will informed me that visitors were particularly interested in how DNA sequencing over the last decade has advanced our understanding of the evolution of plants. He explained that a lot of this work has been carried out by the Angiosperm Phylogeny Group (APG) – an informal group of systematic botanists from around the world who are trying to reach a consensus on the taxonomic groupings of flowering plants. In fact, one of the phylogenetic trees produced by the APG is displayed on a visitor information board in the Botanic Garden.
The roots of a prestigious society
Additional information on plant classification included details about the Linnean Society of London. This society was founded in 1778 and named after the famous Swedish scientist Carl Linnaeus (1707-1778). The aims of the society are to “inspire and inform the public in all areas of natural history through its broad range of events and publications”.
The society maintains the vast animal and plant collections of Carl Linnaeus (the Linnean Herbarium holds some 14,300 specimens alone), looks after his personal library as well as having its own extensive research library. The society has a hugely prestigious past and it was at a society meeting in 1858 that Charles Darwin and Alfred Russel Wallace presented papers relating to the theory of evolution by natural selection! The society today continues to report on scientific advances and holds a number of events (including a student lecture series) throughout the year ranging from the genetic diversity of farmed animals to the future of plant conservation.
Opportunities for hands-on learning
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| Daisy pollen in oil under a light microscope. Image courtesy of microscopy-uk.org.uk/ |
For those members of the general public that enjoy hands-on learning, the Botanic Garden had some dissecting and light microscopes available to look at various plant structures. Under one microscope there was some daisy pollen, which I heard one member of the general public describe as resembling “those spiky looking naval mines”.
Fascination of Plants Day is held each May, so be sure to join us in the Garden for this worthwhile event next year! And don’t forget to come down to the Festival of Nature this weekend (13th-14th June) learn about pitcher plant research, soil and so much more!