The colonial legacy of herbaria.

Herbarium collections shape our understanding of Earth's flora and are crucial for addressing global change issues. Their formation, however, is not free from sociopolitical issues of immediate relevance. Despite increasing efforts addressing issues of representation and colonialism in natural history collections, herbaria have received comparatively less attention. While it has been noted that the majority of plant specimens are housed in the Global North, the extent and magnitude of this disparity have not been quantified. Here we examine the colonial legacy of botanical collections, analysing 85,621,930 specimen records and assessing survey responses from 92 herbarium collections across 39 countries. We find an inverse relationship between where plant diversity exists in nature and where it is housed in herbaria. Such disparities persist across physical and digital realms despite overt colonialism ending over half a century ago. We emphasize the need for acknowledging the colonial history of herbarium collections and implementing a more equitable global paradigm for their collection, curation and use.

Himalayan orogeny and monsoon intensification explain species diversification in an endemic ginger (Hedychium: Zingiberaceae) from the Indo-Malayan Realm.

The Indo-Malayan Realm is a biogeographic realm that extends from the Indian Subcontinent to the islands of Southeast Asia (Malay Archipelago). Despite being megadiverse, evolutionary hypotheses explaining taxonomic diversity in this region have been rare. Here, we investigate the role of geoclimatic events such as Himalayan orogeny and monsoon intensification in the diversification of the ginger-lilies (Hedychium J.Koenig: Zingiberaceae). We first built a comprehensive, time-calibrated phylogeny of Hedychium with 75% taxonomic and geographic sampling. We found that Hedychium is a very young lineage that originated in Northern Indo-Burma, in the Late Miocene (c. 10.6 Ma). This was followed by a late Neogene and early Quaternary diversification, with multiple dispersal events to Southern Indo-Burma, Himalayas, Peninsular India, and the Malay Archipelago. The most speciose clade IV i.e., the predominantly Indo-Burmese clade also showed a higher diversification rate, suggesting its recent rapid radiation. Our divergence dating and GeoHiSSE results demonstrate that the diversification of Hedychium was shaped by both the intensifications in the Himalayan uplift as well as the Asian monsoon. Ancestral character-state reconstructions identified the occurrence of vegetative dormancy in both clades I and II, whereas the strictly epiphytic growth behavior, island dwarfism, lack of dormancy, and a distinct environmental niche were observed only in the predominantly island clade i.e., clade III. Finally, we show that the occurrence of epiphytism in clade III corresponds with submergence due to sea-level changes, suggesting it to be an adaptive trait. Our study highlights the role of recent geoclimatic events and environmental factors in the diversification of plants within the Indo-Malayan Realm and the need for collaborative work to understand biogeographic patterns within this understudied region. This study opens new perspectives for future biogeographic studies in this region and provides a framework to explain the taxonomic hyperdiversity of the Indo-Malayan Realm.

Generating DNA sequence data with limited resources for molecular biology: Lessons from a barcoding project in Indonesia.

The advent of the DNA sequencing age has led to a revolution in biology. The rapid and cost-effective generation of high-quality sequence data has transformed many fields, including those focused on discovering species and surveying biodiversity, monitoring movement of biological materials, forensic biology, and disease diagnostics. There is a need to build capacity to generate useful sequence data in countries with limited historical access to laboratory resources, so that researchers can benefit from the advantages offered by these data. Commonly used molecular techniques such as DNA extraction, PCR, and DNA sequencing are within the reach of small laboratories in many countries, with the main obstacles to successful implementation being lack of funding and limited practical experience. Here we describe a successful approach that we developed to obtain DNA sequence data during a small DNA barcoding project in Indonesia.