Palm Demography Is Biased Towards Neotropical and Human-Used Species, While the Richest Biogeographic Region and Threatened Taxa Are Neglected

Abstract

Demographic studies are essential for understanding how species populations respond over time to environmental conditions and anthropogenic pressures. This knowledge is crucial for developing effective conservation and management strategies. The Arecaceae family (palms), comprising approximately 2500 species, plays significant ecological and socio-economic roles but faces constant threats due to land-use changes and harvesting. Although numerous demographic studies have been conducted, no comprehensive synthesis exists to identify gaps and achievements within this field for Arecaceae, which could guide future research efforts. This study provides an overview of current knowledge on Arecaceae demography. Through a systematic review, 59 demographic studies were identified, totaling 181 study cases. A total of 29 genera and 44 species were recorded, with Chamaedorea radicalis, a human-used species, the most frequently studied. Species classified as Least Concern in the IUCN Red List were the most commonly sampled. The Neotropical region had the highest representation, with Mexico, Colombia, and Brazil as the main contributors. In contrast, the Indo-Malayan biogeographic region, which harbours the highest palm species richness, had only one recorded demographic study. The Matrix Projection Model was the most widely used demographic analysis method, followed by the Integral Projection Model. The average sampling time was 2.43 years. Despite the substantial number of demographic studies on Arecaceae, significant gaps remain, particularly in regions and countries with higher species richness and among species classified as threatened. Future research should prioritise underrepresented taxa and regions, as well as long-term monitoring efforts to enhance conservation strategies.