Phylogeny
This plant is currently accepted by plant systematists as the most basal lineage in the angiosperms clade. By "most basal", scientists mean that the Amborellaceae diverged the earliest from all other lineages of flowering plants. Comparing the derived characteristics that all other angiosperms share with each other, but not with the Amborella Family, may give scientists clues to what features early flowering plants had and how these characteristics have evolved through time. One early twentieth century idea of "primitive", or less derived, angiosperms that was accepted until relatively recently was modeled on the Magnolia blossom with numerous parts arranged in spirals on an elongated receptacle rather than the small numbers of parts in distinct whorls of more derived flowers. However, studies of a well-preserved fossil putative aquatic angiosperm, Archaefructus, have raised questions about what characteristics are more ancestral.
In a study designed to clarify relationships between the well-sequenced and well-studied model plants such as Arabidopsis thaliana, and the basal angiosperms such as Amborella, Nuphar of the Nymphaeaceae, Illicium, the monocots, and more derived angiosperms, the eudicots, scientists examined the chloroplast genomes and expressed sequence tags of these organisms, and other seed plants to create this cladogram. Note that in this image, the angiosperms are all of the plants not labeled "gymnosperms." This hypothesized relationship of the extant seed plants places Amborella as the sister taxon to all other angiosperms, and shows the gymnosperms as a monophyletic group sister to the angiosperms, supporting the theory that Amborella branched off earliest from all other living angiosperms. The dashed line between Amborella and Nuphar is meant to indicate some uncertainty about the relationship between the Amborellaceae and the Nymphaeaceae, and whether or not they form a clade that is sister to the angiosperms, rather than Amborella alone being a monophyletic group sister to the angiosperms.
Because of its evolutionary position at the base of the flowering plant clade, there has been support for sequencing the complete genome of Amborella trichopoda to serve as a reference for evolutionary studies. In 2010, the US National Science Foundation began a genome sequencing effort in Amborella, and the draft genome sequence was posted on the project website in January 2012. The species was featured in the second episode of the BBC documentary series How to Grow a Planet, where Professor Iain Stewart described it as the "closest living relative of the first flower to evolve."
Read more about this topic: Amborella