Pollination Biology of Mesozoic Insects

The Mesozoic era witnessed the origin and early diversification of insect–plant pollination interactions long before the dominance of modern flowering plants. During the Triassic and Jurassic, numerous lineages of long-proboscid insects—such as scorpionflies, lacewings and early neuropterans—fed on gymnosperm pollination drops, using specialised siphonate mouthparts to access ovulate fluids. By the mid-Cretaceous, the rise of angiosperms introduced novel floral morphologies and rewards, driving the emergence of new pollination syndromes. Amber-preserved specimens reveal intricate mouthpart adaptations in beetles, wasps and early bees, often bearing gymnosperm or eudicot pollen on hairs and oral structures. These fossils document shifts from generalist pollen feeding to specialised associations, illustrating how early pollinators tracked changes in plant reproductive biology. Macroevolutionary analyses further indicate that the angiosperm radiation mitigated insect extinction and later promoted origination of pollinator families, underlining the dual role of flowering plants in shaping insect diversity. The interplay of global climate, plant community shifts and insect innovation during the Mesozoic laid the foundation for modern terrestrial ecosystems and informs our understanding of pollinator resilience under environmental change.

Research from Nature Portfolio

Recent studies employing fossil-record modelling have quantified how the angiosperm radiation influenced insect macroevolutionary rates. Angiosperms are now recognised not only for their later role in driving origination of new pollinating lineages but also for buffering existing insects against extinction during the Cretaceous crisis. Detailed palaeobiological investigations of mid-Cretaceous amber have uncovered direct evidence of pollen-feeding behaviour in basal stinging wasps: hundreds of eudicot pollen grains were recovered from mouthparts and buccal cavities, demonstrating active foraging on early flowering plants. Meanwhile, investigations of long-proboscid scorpionflies from Burmese amber have elucidated complex mouthpart pump systems linked to gymnosperm pollination, revealing multiple independent origins of siphonate feeding structures and strengthening the connection between niche specialisation and morphological innovation.

Pollination Biology of Mesozoic Insects publication trend

The graph below shows the total number of articles in pollination biology of mesozoic insects across all publications each year (not limited to Nature Index journals).

Technical terms

Proboscis: An elongated, tubular mouthpart adapted for sucking fluids, as seen in long-proboscid Mecoptera and Neuroptera.

Pollination drop: A fluid secreted by gymnosperm ovules that attracts insects and provides nutrient rewards.

Gymnosperm: A group of seed plants—including cycads and conifers—that release pollination drops and preceded angiosperms.

Angiosperm: Flowering plants characterised by enclosed ovules and specialised floral structures, whose radiation reshaped pollinator communities.

Eudicot: A major clade of angiosperms with tricolpate pollen, representing a large proportion of modern flowering plant diversity.

References

1. The angiosperm radiation played a dual role in the diversification of insects and insect pollinators. Nature Communications (2024).
2. Life habits and evolutionary biology of new two-winged long-proboscid scorpionflies from mid-Cretaceous Myanmar amber. Nature Communications (2019).
3. New data from the Middle Jurassic of China shed light on the phylogeny and origin of the proboscis in the Mesopsychidae (Insecta: Mecoptera). BMC Ecology and Evolution (2016).
4. Generalist Pollen-Feeding Beetles during the Mid-Cretaceous. iScience (2020).
5. High niche diversity in Mesozoic pollinating lacewings. Nature Communications (2018).
6. Direct evidence for eudicot pollen-feeding in a Cretaceous stinging wasp (Angiospermae; Hymenoptera, Aculeata) preserved in Burmese amber. Communications Biology (2019).
7. 100 Ma sweat bee nests: Early and rapid co-diversification of crown bees and flowering plants. PLOS ONE (2020).