Origin and evolution of the Micronesian biota: Insights from molecular phylogenies and biogeography reveal long‐distance dispersal scenarios and founder‐event speciation

Abstract

Micronesian islands taxa show high endemism rates, but very little is known about their biogeographical histories. The lack of systematic biogeography is mainly due to insufficient phylogenetic research in Micronesia. With the recent increase in published molecular biogeographic data, we were able to, for the first time, answer fundamental biogeography questions by reviewing and analyzing numerous geological, ecological, and evolutionary studies. This review, in addition to providing an overview of Micronesian geological history, confirmed the importance of long‐distance dispersal mechanisms and founder‐event speciation, and morphological and physiological adaptations of plant propagules to cross vast stretches of ocean by wind, ocean currents, bird, or bat dispersal. These adaptations to habitat and geological features, including reef types, determined colonization success as well as inland dispersal and speciation mechanisms. We further identified the source areas of the Micronesian biota and reconstructed historical dispersal scenarios: a dominant Austro‐Melanesian dispersal scenario, an Indo‐Malaysian connecting to the Austro‐Melanesian dispersal scenario, and a Neotropical American and an African dispersal scenario toward Micronesia. Most generic origins were estimated between the Eocene and the Miocene and dispersed to Micronesia between the Miocene and the Pleistocene.

Phylogenomic assessment prompts recognition of the Serianthes clade and confirms the monophyly of Serianthes and its relationship with Falcataria and Wallaceodendron in the wider ingoid clade (Leguminosae, Caesalpinioideae)

“…Of this clade, Serianthes is the only genus with Pacific Island representatives, while Falcataria is the only genus occurring in Australia. Serianthes is the most widespread, most likely because of its indehiscent pods, which are dispersed via ocean currents ( Demeulenaere and Ickert-Bond 2022 ).…”

Slowing taxon cycle can explain biodiversity patterns on islands: Insights into the biogeography of the tropical South Pacific from molecular data

“…We identified relevant literature by searching the Web of Science using the keywords “Pacific AND island* AND phylo*.” Results were supplemented with references in synthesis studies that reviewed phylogenetic relationships in the tropical South Pacific (Keppel et al, 2009) or in particular archipelagos within this region: Galapagos (Parent et al, 2008; García‐Verdugo et al, 2014), Hawaii (Price & Wagner, 2018), Marquesas (Hembry, 2018), Micronesia (Demeulenaere & Ickert‐Bond, 2022), and New Caledonia (Pillon, 2012; Nattier et al, 2017). We excluded studies for which sampling did not cover large portions of a taxon's distribution, such as studies with detailed sampling in only one or two archipelagos for taxa found in many Pacific archipelagoes.…”

“…Furthermore, the biodiversity of independent island nations has been little studied compared to territories administered by nations outside the insular Pacific (Keppel et al, 2012; Brodie et al, 2013). This is exemplified by studies using aggregated molecular studies being restricted to the predominantly externally controlled regions of the Galapagos (Parent et al, 2008; García‐Verdugo et al, 2014), Hawaii (Price & Wagner, 2018), Marquesas (Hembry, 2018), Micronesia (Demeulenaere & Ickert‐Bond, 2022), and New Caledonia (Pillon, 2012; Nattier et al, 2017). A holistic picture of the history and evolution of biodiversity in the tropical Pacific is therefore lacking.…”

A Review of the Ethnomedicinal, Phytochemical, and Anticancer Properties of Melicope Species

“…[3] They are widely distributed in Asia, Australia, the Indian Ocean Islands, Madagascar, and the Pacific Islands. [4] The species in the genus are evergreen and vary from shrubs to mostly dioecious trees. Depending on the species, the leaves are trifoliate or unifoliate, with dry to fleshy fruits.…”

“…and Euodia J. R. Forst, where in some cases, they are synonyms [3] . They are widely distributed in Asia, Australia, the Indian Ocean Islands, Madagascar, and the Pacific Islands [4] . The species in the genus are evergreen and vary from shrubs to mostly dioecious trees.…”