Phylogenetics and Evolution of Terrestrial Plant Adaptations

The transition of plants from aquatic to terrestrial environments represents one of the most transformative events in Earth’s history. Phylogenetic analyses of green algae and embryophytes have elucidated a single origin of land plants from streptophyte algal ancestors, with successive diversification into bryophytes, lycophytes, ferns and seed plants. Genomic and transcriptomic comparisons reveal that key innovations—such as the elaboration of cell‐wall biosynthetic pathways, the acquisition and diversification of phytohormone signalling networks, and expansions of transcription‐associated protein families—preceded or accompanied the colonisation of land. Morphological and physiological traits, including desiccation tolerance, ultraviolet screening by phenolic compounds, and complex multicellular organisation, arose through coordinated gene family gains and regulatory rewiring. Stress‐response modules originally adapted to fluctuating freshwater and subaerial habitats were co-opted for terrestrial challenges. The resulting evolutionary framework not only clarifies sister-group relationships among streptophyte algae and embryophytes, but also underpins modern efforts to engineer crops with enhanced resilience to drought, temperature extremes and soil constraints. By integrating molecular phylogenetics with functional biology, current research offers a comprehensive account of how plants conquered land and continues to inform ecological restoration, sustainable agriculture and climate-adaptive breeding programmes.

Research from Nature Portfolio

Phytohormone profiling across the Viridiplantae has demonstrated that many signalling molecules such as auxin, cytokinin and salicylic acid were already present in charophyte algae, whereas certain conjugated forms emerged only in land plants, highlighting stepwise elaboration of hormonal control. Fine-grained stress‐response experiments with Mesotaenium under variable light and temperature regimes have uncovered conserved genetic network “hubs” that pre‐date terrestrialisation, indicating that lipid droplet formation and cell-wall signalling were ancient features of streptophyte stress tolerance. Complementary genome assemblies of early-diverging streptophyte algae reveal that embryophyte-type photorespiration, canonical phytochromes and cellulose synthase-like genes were established before full colonisation of land, suggesting that the ancestral streptophyte toolkit was pre-adapted for subaerial environments.

Phylogenetics and Evolution of Terrestrial Plant Adaptations publication trend

The graph below shows the total number of articles in phylogenetics and evolution of terrestrial plant adaptations across all publications each year (not limited to Nature Index journals).

Technical terms

Phylogenetics: The reconstruction of evolutionary relationships among organisms using genetic or morphological data.

Streptophyte algae: A lineage of green algae including the closest living relatives of land plants.

Terrestrialization: The evolutionary process by which aquatic ancestors adapted to life on land.

Phytohormones: Endogenous signalling molecules that regulate plant growth, development and stress responses.

Transcription-associated proteins (TAPs): Regulatory factors involved in control of gene expression and developmental pathways.

Extracellular matrix (ECM): The network of polysaccharides and proteins outside the cell that provides structural support and mediates environmental interactions.

References

1. Phytohormone profiling in an evolutionary framework. Nature Communications (2024).
2. Environmental gradients reveal stress hubs pre-dating plant terrestrialization. Nature Plants (2023).
3. The extracellular matrix of green algae. Plant Physiology (2023).
4. Enhanced sensitivity of TAPscan v4 enables comprehensive analysis of streptophyte transcription factor evolution. The Plant Journal (2024).
5. Genomes of early-diverging streptophyte algae shed light on plant terrestrialization. Nature Plants (2019).