Read the full-length paper 'Inequality in plant diversity knowledge and unrecorded plant extinctions': An example from the grasses of Madagascar' here.

Madagascar’s grasses. Eighteen species have been missing since at least 2011 and may have become extinct without anyone realising. Credit: Maria Vorontsova

1. This paper addresses two different subject areas – unrecorded plant extinctions, and complex inequality facing botanists in Madagascar. We argue that these two things are related, and inequality is a driver of unrecorded extinctions.

2. More than 500 plant species are already presumed extinct and many more could have been lost without anyone being aware, especially in species-rich areas with high levels of human impact, where botanical knowledge is poor. Inequality in the availability and accessibility of plant diversity data, professional expertise, and funding interact to produce chronic differences in knowledge between countries.

Global patterns of plant extinction and rediscovery. A. Proportions of native plant species which are presumed extinct. Low proportions (%) in blue, through greens, yellows and to high proportions (%) in red. B. Numbers of extinct (non-rediscovered) and rediscovered species. The colours illustrate the number of extinct and rediscovered plant species recorded in each area: pink indicates extinctions, green indicates rediscoveries, and mixed shades indicate both extinction and rediscovery. Dark grey indicates more than one extinction as well as more than one rediscovery. Light grey indicates no record of a globally extinct plant. Data from Humphreys et al. (2019) and WCSP (2018). Credit: all authors.

2. The flora of Madagascar has been described largely by foreigners, science funding is external, and Malagasy botanists face multiple challenges including poor roads, unsafe field locations, small underfunded local herbarium collections, poor education, poor access to the internet, and poor access to published material as well as to opportunities to publish.

Madagascar’s biggest herbarium. Most specimens of Malagasy grasses are held abroad. A quarter of the Madagascar’s grass species are missing from the island’s biggest herbarium at the Parc botanique et zoologique de Tsimbazaza, so species identification in Madagascar is often impossible. Credit: Maria Vorontsova.

2. Unrecorded extinctions are more likely among Malagasy than British and Irish grasses: they were described later, have smaller ranges, and are more threatened. It is possible that extinction rates of Malagasy grasses will increase tenfold in the next century.
    
3. Differences in our knowledge of the Malagasy and British floras are long-standing, deep, and perpetuated by numerous modern-day factors. We urge researchers to understand and acknowledge these differences, and we provide examples of good modern work practice by co-authors Sylvie Andriambololonera (IUCN Species Survival Commission, Madagascar Plant Specialist Group) and Lucienne Wilmé (journal Madagascar

The first author Maria Vorontsova has studied the grasses of Madagascar and the British Isles for 10 years, spending time in both countries. In this paper she uses grasses as an example to compare levels of botanical knowledge and their historical and contemporary causes in both countries. Plant evolutionary biologist Aelys Humphreys at Stockholm University analysed the data to see whether inequality increased the chances of unrecorded extinctions. Sylvie Andriambololonera, Andriambolantsoa Rasolohery, Lucienne Wilmé and Pete Lowry have all contributed their knowledge of botany in Madagascar.