Bayesian Methods to Analyze Historical Collections in Time and Space: A Case Study Using Cabo Verde Endemic Flora

Abstract

Biological collections, including herbarium specimens, are unique sources of biodiversity data presenting a window on the history of the development and accumulation of knowledge of a specific geographical region. Understanding how the process of discovery impacts that knowledge is particularly important for oceanic islands which are often characterized by both high levels of endemic diversity and high proportions of threatened taxa. The archipelagos of the Macaronesian region (i.e. Azores, Canaries, Savages, Madeira, and Cabo Verde) have been the focus of attention for scientific expeditions since the end of the 17th century. However, there is no integrated study describing the historical process of collecting, discovery and description of its flora. Using as a case study the Cabo Verde endemic angiosperm flora, we review the history of collecting in the flora and apply a Bayesian approach to assess the accumulation of species discovery, through time and space across the nine islands of the archipelago. Our results highlight the central role not only of natural characteristics (e.g. area, age, maximum altitude and average value of the terrain ruggedness index) but also historical factors (i.e. the location of major harbors) for the development of knowledge of the flora. The main factors that have determined the process of species description in the archipelago and how this impact our understanding of diversity patterns across archipelagos are discussed.

Cabo Verde’s Poaceae Flora: A Reservoir of Crop Wild Relatives Diversity for Crop Improvement

“…Since the end of the journeys to the Antilles and the establishment of regular trade with Brazil, maize became the food basis of the Cabo Verdean population (Santos and Torrão, 1998) and is currently a dominant part of their diet (Monteiro et al, 2020). The importance of historical factors and the role played by Cabo Verde in the Atlantic navigation during the 16th-19th centuries (Romeiras et al, 2020), contributed to change and determine the present composition of Cabo Verde's flora, with more than 70% of exotic species, most of them introduced for food purposes. Therefore, the valorisation of the plant genetic resources related to millet crops and their wild relatives is of major importance to fight hunger and ensure food and nutrition security in Cabo Verde.…”

Tackling Food Insecurity in Cabo Verde Islands: The Nutritional, Agricultural and Environmental Values of the Legume Species

“…740 vascular plant taxa, of which ca. 92 are endemic [6]. In a recent conservation assessment based on the International Union for Conservation of Nature (IUCN) Red list criteria, ca.…”

“…Also, during human settlement, the introduction of useful plants was of chief importance to change the present-day composition of the archipelago's flora, which comprises a great number of exotic taxa [10]. Historical contingencies, namely the location of the main harbours (i.e., Mindelo, in São Vicente, and Cidade da Praia, in Santiago) and the establishment of the first settlements greatly impacted the knowledge of local flora and the botanical explorations in this archipelago [6].…”

Diversification of Aeonium Species Across Macaronesian Archipelagos: Correlations Between Genome-Size Variation and Their Conservation Status

“…The climate of this archipelago is tropical dry, and the altitude and the north-east trade winds are key factors in shaping species distribution (Neto et al, 2020). The knowledge of the Cabo Verde flora lagged far behind the central Macaronesian archipelagos of the Canaries and Madeira, and there is still incomplete knowledge about the taxonomy and geographic distribution of most species (Romeiras et al, 2020).…”