Paleobotanical Insights into South American Flora

Fossil plants from South America offer a window into the evolution, distribution and ecological dynamics of ancient floras on the former Gondwanan landmass. From the early Palaeocene recovery after the end-Cretaceous extinction to greenhouse intervals in the Eocene, palaeobotanical records reveal shifts in diversity, biogeographic connections and community structure. Key sites in Patagonia and Tierra del Fuego preserve a range of macrofossils—leaves, woods, flowers and infructescences—as well as spores and pollen that document the presence of lineages now confined to Australasia, Malesia or tropical regions. These data demonstrate early dispersal of eucalypts and conifers beyond their modern ranges, survival of Gondwanan taxa through climatic upheavals and the assembly of diverse rainforests at high southern latitudes. Integrating palaeoclimate reconstructions with taxonomic and anatomical studies has elucidated the drivers of diversification and extinction, highlighting ancient parallels with today’s carbon-rich ecosystems and offering deep-time perspectives on plant responses to elevated CO₂ and warming.

Research from Nature Portfolio

A comprehensive study of insect feeding and fungal interactions on Agathis leaves from late Cretaceous to middle Eocene sites in Patagonia reveals remarkably similar damage patterns to those on living Agathis in Asia and the Pacific. This continuity of leaf-mines, galls, scale insect covers and rust fungus suggests that entire ecological guilds persisted on a single host lineage as it migrated across shifting plates, underscoring the long-term stability of host–herbivore–pathogen associations. Another investigation quantifies spore and pollen diversity across pre-, mid- and post-Eocene Climatic Optimum intervals in southern Patagonia. Diversity rose by about 40 % during the greenhouse peak, driven by the co-occurrence of neotropical migrants and relict Gondwanan elements. This work provides a deep-time analogue for modern high-latitude warming and demonstrates how elevated CO₂ and temperature fostered rich, mixed biotas in an ice-free Southern Hemisphere realm.

Paleobotanical Insights into South American Flora publication trend

The graph below shows the total number of articles in paleobotanical insights into south american flora across all publications each year (not limited to Nature Index journals).

Technical terms

Gondwana: The southern supercontinent composed of present-day South America, Africa, Antarctica, Australia and India during the Mesozoic and early Cenozoic.

Palaeoclimate: The climate conditions prevailing in the geological past, inferred from fossil and sedimentary proxies.

Infructescence: A cluster of fruits derived from a single inflorescence, often preserved intact in the fossil record.

Leaf-mine association: Damage pattern created by insect larvae feeding within leaf tissues, leaving characteristic tunnels or blotches.

Phylogenomic analysis: Reconstruction of evolutionary relationships using genome-scale data, here applied to integrate fossil morphological traits with molecular phylogenies.

References

1. Persistent biotic interactions of a Gondwanan conifer from Cretaceous Patagonia to modern Malesia. Communications Biology (2020).
2. Impact of mid Eocene greenhouse warming on America’s southernmost floras. Communications Biology (2021).
3. Oldest Known Eucalyptus Macrofossils Are from South America. PLOS ONE (2011).
4. Fossil flowers from the early Palaeocene of Patagonia, Argentina, with affinity to Schizomerieae (Cunoniaceae). Annals of Botany (2018).
5. First Evidence for Wollemi Pine-type Pollen (Dilwynites: Araucariaceae) in South America. PLOS ONE (2013).