Phylogenetic Analysis of Basal Angiosperms

Basal angiosperms constitute the earliest-diverging lineages of flowering plants, encompassing the so-called ANA-grade of Amborellales, Nymphaeales and Austrobaileyales. Phylogenetic analysis in this context combines morphological traits with extensive molecular data to resolve branching order, divergence times and genomic innovations that underpinned the rapid rise of angiosperms. Key approaches include the sequencing of whole nuclear and plastid genomes, targeted enrichment of orthologous nuclear loci and the integration of fossil calibration to infer both topology and timing. Such efforts have illuminated ancient whole-genome duplication events, clarified the sister-group relationships of water lilies and Amborella to all other extant flowering plants, and provided a robust framework for interpreting the evolution of floral organ identity, reproductive strategies and biogeographical patterns. Beyond fundamental insights into angiosperm origins, these analyses inform conservation priorities for relictual lineages and underpin comparative studies of trait evolution across the angiosperm tree of life.

Research from Nature Portfolio

One foundational study presented the high-quality genome assembly of a blue-petalled water lily, revealing that Nymphaeales and Amborellales are successive sister lineages to all other extant angiosperms. Comparative phylogenomic analyses identified a lineage-specific whole-genome duplication event in the water lily lineage, which appears to have contributed to the retention of key regulatory genes involved in flowering transition and organ development. Broad expression of ancestral ABCE floral-identity genes supports a model in which early angiosperms possessed a broadly active programme for organ determination. The genome also uncovered parallel evolution of floral scent and pigment biosynthetic pathways shared with more derived mesangiosperms, underscoring convergent innovation in floral attraction mechanisms.

Phylogenetic Analysis of Basal Angiosperms publication trend

The graph below shows the total number of articles in phylogenetic analysis of basal angiosperms across all publications each year (not limited to Nature Index journals).

Technical terms

Basal angiosperms: Earliest-diverging lineages of flowering plants, including Amborella, water lilies and Austrobaileyales.

Phylogenomics: Reconstruction of evolutionary relationships using genome-scale sequence data.

Plastid genome: The circular DNA of chloroplasts, often used in plant phylogenetics.

Whole-genome duplication: An event in which an organism’s entire genetic material is duplicated, providing raw material for evolutionary innovation.

Vicariance: Geographic separation of populations by barriers, leading to speciation.

Long-distance dispersal: Movement of propagules across significant geographic barriers, contributing to range expansion.

References

1. The water lily genome and the early evolution of flowering plants. Nature (2019).
2. Climatic niche evolution and niche conservatism of Nymphaea species in Africa, South America, and Australia. BMC Plant Biology (2024).
3. Revised Species Delimitation in the Giant Water Lily Genus Victoria (Nymphaeaceae) Confirms a New Species and Has Implications for Its Conservation. Frontiers in Plant Science (2022).
4. Reconstructing the age and historical biogeography of the ancient flowering-plant family Hydatellaceae (Nymphaeales). BMC Ecology and Evolution (2014).