BSBI at the 2024 International Botanical Congress in Madrid: Days 5-7

This is the third and final report by BSBI trustee Richard Allanach from the XX International Botanical Congress in Madrid, following on from Days 1&2 and Days 3&4. 

Over to Richard:

"Amongst the five lectures and 54 symposia delegates could attend on Thursday there was still plenty of opportunity for botanists to meet and plan future activity. Current and future BSBI Presidents Micheline Sheehy Skeffington and Paul Ashton met with Xavier Pico of our sister society, the Spanish Botanical Society (SEBOT), to discuss future collaboration. Xavier is lucky enough to work in the Donana, a fabulous wetland area in southern Spain - home to lynxes, hoopoes and the sage- leaved rockrose. In the image on the right, BSBI correspondent Richard Allanach hovers to the right of the gathering.

Friday at the twentieth International Botanical Congress in Madrid was definitely Commonwealth Day. For reasons of narrative clarity we will describe it back to front. The major public lecture which closed the day was about RBG Kew's’ series of reports on the ‘State of the World’s plants and fungi’ in which BSBI is a partner and contributes data to the reports.

Headline – half of the world’s flowering plant species are threatened with extinction. Prof Alexandre Antonelli, Director of Science at RBG Kew, referred to the well known concept of floristic hotspots. The next International Botanical Congress in 2029 will be held in the middle of flowering season in the floral hotspot of Cape Province, South Africa (9,500 plant species, 68% endemic). As well as floral hotspots, Prof Antonelli introduced the concept of floral "dark spots" based first on the probable number of undiscovered plant species and secondly on our geographical knowledge of the spread of each species. Unsurprisingly, and thanks to the work of BSBI members over many decades, our islands were placed at the polar opposite end of the spectrum from the world’s dark spots. Prof Antonelli believes we have few undiscovered species (but see below). However then came a moment for Hiberno-Britannic pride. Whilst our islands and France are ranked equally for likely undiscovered species it is believed our geographical knowledge of the species we have is significantly better than our Gallic neighbours. Indeed a French delegate to the BSBI stand acknowledged that Plant Atlas 2020 was significantly better than anything our Trans-Manche cousins have, before he concluded that because of the greater floral diversity of France if they had produced a Flora similar to our own it would have taken four volumes rather than our paltry two.

An encouraging feature of the Congress was the number of delegates from India. Their team of 68 botanists was the tenth largest delegation and comfortably exceeded the sum of delegates from the entire continent of Africa. Naturally many Indian delegates came and talked to us on the BSBI stand. Hopefully this might lead to future collaboration.

Saturday: The first lecture of the day raised an interesting possibility that RBG Kew might be wrong and that our islands hold as yet unclassified new species. Prof Angela Moles of the University of New South Wales, Australia spoke about climate change and the movement of plant species. A paradox is that a third of studied species are heading in the “wrong” direction towards a warmer climate. She also spoke about a South African aster Arctotheca populifolia (beach daisy) which was first recorded in Australia less than 100 years ago. The Australian population was morphologically distinct, flowers at a different time of year and even when forced to breed in a lab experiment has a very low rate of setting viable seed. On that basis Prof Moles argued the Australian population could be classed as a new species. Given the propensity of our Victorian forebears to bring back specimens from all over their world and their subsequent escape into the wild surely some could meet the same levels of morphological distinctness and theoretical and practical gene isolation. They will have had decades longer than the beach daisy to become independent of their parent population.

If you had fallen asleep after Sandra Knapp’s opening lecture ‘Why Botany, Why Now?’ on the opening day of the XX International Botanical Congress and not woken up until twenty to four on the final afternoon you might have thought the entire event was dominated by BSBI speakers. In the final slot before the closing ceremony, BSBI President-Elect Prof Paul Ashton (image on right) spoke about how genes flow across our environment. Prof Ashton took three species: Water Sedge Carex aquatilis, Meadow Crane's-bill Geranium pratense and Downy-fruited Sedge Carex filiformis, and used his own research to report on their genetic diversity in our islands. His lecture was well illustrated with distribution information from BSBI's Plant Atlas 2020 and among other matters he concluded that in Britain, Carex filiformis was now fragmented into genetically isolated populations, with all the threats to future survival that poses. He concluded his lecture with a rousing call for conservation action directed to renewing the corridors that enable genes to flow between different plant species populations. 

After Paul’s lecture all that remained was the closing ceremony and the adoption of the rather wordy Madrid Declaration - doubtless many BSBI members will be pleased that improved support for herbaria made it into the first point of the ten points of the declaration".

Huge thanks to Richard for these reports from the International Botanical Congress!