The Cretaceous Terrestrial Revolution (abbreviated KTR), also known as the Angiosperm Terrestrial Revolution (ATR) by authors who consider it to have lasted into the Palaeogene, describes the intense floral diversification of flowering plants (angiosperms) and the coevolution of pollinating insects, as well as the subsequent faunal radiation of frugivorous, nectarivorous and insectivorous avians, mammals, lissamphibians, squamate reptiles and web-spinning spiders during the Middle to Late Cretaceous, from around 125 Mya to 80 Mya. Alternatively, according to Michael Benton, the ATR is proposed to have lasted from 100 Ma, when the first highly diverse angiosperm leaf floras are known, to 50 Ma, during the Early Eocene Climatic Optimum, by which point most crown lineages of angiosperms had evolved.
Appearance of angiosperms
Molecular clock analyses of angiosperm evolution suggest that crown group angiosperms may have diverged up to 100 million years before the start of the KTR, although this is possibly due to artefacts of the inabilities of molecular clock estimates to account for explosive accelerations in evolution that may have caused the extremely fast diversification of angiosperms shortly after their first appearance in the fossil record.
Causes
The KTR was enabled by the dispersed positions of the continents and the formation of new oceans during the Cretaceous in the aftermath of Pangaea's breakup in the preceding Jurassic period, which enhanced the hydrological cycle and promoted the expansion of temperate climatic zones, fuelling radiations of angiosperms. Among mammals, enhanced tectonic activity generated diversity increases by increasing montane habitats, which promote increased diversity in hot climates.
Another cause of the explosive angiosperm diversification was the evolution of leaf vein densities greater than 2.5–5 mm/mm, when the leaf interior transport path length of water became shorter than the leaf interior transport path length of CO2. This enabled greater utilisation of CO2 and gave an evolutionary advantage to flowering plants over conifers because they could sequester more CO2 for the same amount of water. The much greater capacity of angiosperms for assimilating CO2 sharply increased global bioproductivity.
The drying of many terrestrial ecosystems during the Middle Cretaceous Hothouse (MKH) benefitted angiosperms, which were able to survive hot and dry environments, and the increased fire activity helped to enhance diversification of angiosperms. Angiosperms enabled more frequent fires than gymnosperms, and they also recovered more quickly from fires than gymnosperms did. This created a feedback loop that advantaged angiosperms over gymnosperms during the Cretaceous.
Biotic effects
Although angiosperm diversity drastically grew over the Cretaceous, this did not necessarily translate to ecological dominance, which they only achieved in the Early Cenozoic.
Angiosperms responded to increasing coevolution with frugivores by enlarging the sizes of their fruits, which peaked during the Early Eocene.
Before Lloyd et al.'s 2008 paper described the KTR, it had been widely accepted in paleontology that new families of dinosaurs evolved during the Middle to Late Cretaceous, including the euhadrosaurs, neoceratopsians, ankylosaurids, pachycephalosaurs, carcharodontosaurines, troodontids, dromaeosaurs and ornithomimosaurs. However, the authors of the paper have suggested that the apparent "new diversification" of dinosaurs during this time is due to sampling biases in the fossil record, and better preserved fossils in Cretaceous age sediments than in earlier Triassic or Jurassic sediments. However, later studies still suggest the possibility that the KTR caused a rise in dinosaur diversity. Dinosaurs contributed little to angiosperm diversification, which was instead mainly driven by coevolution with other animals, such as insects and herbivorous mammals. It has been suggested that some pterosaurs may have been seed dispersers symbiotically linked to angiosperms. A comprehensive molecular study of evolution of mammals at the taxonomic level of family also showed important diversification during the KTR. Mammals have been found to have decreased in disparity during the KTR.
Insect diversity overall appears to have been minimally affected by the KTR, as molecular evidence shows that the increase in diversity of pollinating insects was asynchronous with the KTR. However, Early Cretaceous angiosperms were short in stature and would have been heavily reliant on insect pollination, and fossil remains of early angiosperms suggest such a dependence on zoophilous pollination. Genetic evidence indicates a major radiation of phasmatodeans occurred during the KTR, likely in response to a coeval radiation of enantiornitheans and other visual predators. Ants likewise underwent massive increase in diversity as part of the KTR. Similarly, bee pollinator diversification strongly correlates with angiosperm flower appearance and specialization during the same era. Flies, already successful pollinators before the rise of angiosperms, quickly adapted to the new hosts. Beetles became pollinators of angiosperms by the earliest part of the Late Cretaceous. Lepidopterans radiated during the KTR, though the angiosperm radiation is insufficient in and of itself to completely account for their diversification. Among one lineage of sawflies, there was a change in preferred host plants amidst the biotic reorganisation of the KTR. Not all insects were advantaged by this diversification and rearrangement of ecosystems; long-proboscid insects that were mainstays of gymnosperm-dominated ecosystems earlier in the Mesozoic underwent a major decline. Late-surviving eoblattodeans evolved long, slim bodies with long external ovipositors in response to the angiosperm radiation, but this proved to be an evolutionary dead end in the long run and the group went extinct. The so-called "golden age" of neuropterans during the Middle Mesozoic, when gymnosperms dominated the flora, ended with the KTR and its reshaping of the terrestrial environment.
The KTR may have supercharged the contemporary Mesozoic Marine Revolution (MMR) by enhancing weathering and erosion, accelerating the flow of limiting nutrients into the world’s oceans.
For nearly the entirety of Earth's history, including most of the Phanerozoic eon, marine species diversity exceeded terrestrial species diversity, a pattern which was reversed during the Middle Cretaceous as a result of the KTR in what has been termed a biological "great divergence", named after the historical Great Divergence.
See also
References
- ^ Benton, Michael James; Wilf, Peter; Sauquet, Hervé (26 October 2021). "The Angiosperm Terrestrial Revolution and the origins of modern biodiversity". New Phytologist. 233 (5): 2017–2035. doi:10.1111/nph.17822. hdl:1983/82a09075-31f4-423e-98b9-3bb2c215e04b. PMID 34699613. S2CID 240000207. Retrieved 24 November 2022.
- ^ Lloyd, G. T.; et al. (2008). "Dinosaurs and the Cretaceous Terrestrial Revolution. 2008". Proceedings of the Royal Society B: Biological Sciences. 275 (1650): 2483–2490. doi:10.1098/rspb.2008.0715. PMC 2603200. PMID 18647715.
- Barba-Montoya, Jose; Dos Reis, Mario; Schneider, Harald; Donoghue, Philip C. J.; Yang, Ziheng (5 February 2018). "Constraining uncertainty in the timescale of angiosperm evolution and the veracity of a Cretaceous Terrestrial Revolution". New Phytologist. 218 (2): 819–834. doi:10.1111/nph.15011. PMC 6055841. PMID 29399804.
- Gurung, Khushboo; Field, Katie J.; Batterman, Sarah J.; Goddéris, Yves; Donnadieu, Yannick; Porada, Philipp; Taylor, Lyla L.; Mills, Benjamin J. W. (4 August 2022). "Climate windows of opportunity for plant expansion during the Phanerozoic". Nature Communications. 13 (1): 4530. Bibcode:2022NatCo..13.4530G. doi:10.1038/s41467-022-32077-7. PMC 9352767. PMID 35927259.
- Weaver, Lucas N.; Kelson, Julia R.; Holder, Robert M.; Niemi, Nathan A.; Badgley, Catherine (January 2024). "On the role of tectonics in stimulating the Cretaceous diversification of mammals". Earth-Science Reviews. 248: 104630. doi:10.1016/j.earscirev.2023.104630. Retrieved 11 October 2024 – via Elsevier Science Direct.
- de Boer, Hugo Jan; Eppinga, Maarten B.; Wassen, Martin J.; Dekker, Stefan C. (27 November 2012). "A critical transition in leaf evolution facilitated the Cretaceous angiosperm revolution". Nature Communications. 3 (1): 1221. Bibcode:2012NatCo...3.1221D. doi:10.1038/ncomms2217. ISSN 2041-1723. PMC 3514505. PMID 23187621.
- Boyce, C. Kevin; Zwieniecki, Maciej A. (26 June 2012). "Leaf fossil record suggests limited influence of atmospheric CO 2 on terrestrial productivity prior to angiosperm evolution". Proceedings of the National Academy of Sciences of the United States of America. 109 (26): 10403–10408. doi:10.1073/pnas.1203769109. ISSN 0027-8424. PMC 3387114. PMID 22689947.
- Zhang, Mingzhen; Dai, Shuang; Du, Baoxia; Ji, Liming; Hu, Shusheng (25 October 2018). "Mid‐Cretaceous Hothouse Climate and the Expansion of Early Angiosperms". Acta Geologica Sinica. 92 (5): 2004–2025. doi:10.1111/1755-6724.13692. ISSN 1000-9515. Retrieved 11 October 2024 – via Wiley Online Library.
- Bond, William J.; Midgley, Jeremy J. (July 2012). "Fire and the Angiosperm Revolutions". International Journal of Plant Sciences. 173 (6): 569–583. doi:10.1086/665819. ISSN 1058-5893. Retrieved 25 June 2024 – via The University of Chicago Press Journals.
- ^ Friis, E.M.; Pedersen, K. Raunsgaard; Crane, P.R. (22 March 2006). "Cretaceous angiosperm flowers: Innovation and evolution in plant reproduction". Palaeogeography, Palaeoclimatology, Palaeoecology. 232 (2–4): 251–293. Bibcode:2006PPP...232..251F. doi:10.1016/j.palaeo.2005.07.006. Retrieved 20 May 2024 – via Elsevier Science Direct.
- Eriksson, Ove (20 December 2014). "Evolution of angiosperm seed disperser mutualisms: the timing of origins and their consequences for coevolutionary interactions between angiosperms and frugivores". Biological Reviews. 91 (1): 168–186. doi:10.1111/brv.12164. ISSN 1464-7931. PMID 25530412. Retrieved 25 June 2024 – via Wiley Online Library.
- Benton, Michael J. (15 November 2023). "The dinosaur boom in the Cretaceous". Geological Society, London, Special Publications. 544 (1): 70. Bibcode:2023GSLSP.544...70B. doi:10.1144/SP544-2023-70. ISSN 0305-8719.
- Barrett, Paul M.; Willis, Katherine J. (24 August 2001). "Did dinosaurs invent flowers? Dinosaur—angiosperm coevolution revisited". Biological Reviews. 76 (3): 411–447. doi:10.1017/S1464793101005735. ISSN 1464-7931. PMID 11569792. Retrieved 25 June 2024 – via Cambridge Core.
- Fleming, Theodore H.; Lips, Karen R. (October 1991). "Angiosperm Endozoochory: Were Pterosaurs Cretaceous Seed Dispersers?". The American Naturalist. 138 (4): 1058–1065. doi:10.1086/285269. ISSN 0003-0147. Retrieved 30 June 2024 – via The University of Chicago Press Journals.
- Meredith, Robert W. (2011). "Impacts of the Cretaceous Terrestrial Revolution and KPg Extinction on Mammal Diversification". Science. 334 (6055): 521–524. Bibcode:2011Sci...334..521M. doi:10.1126/science.1211028. PMID 21940861. S2CID 38120449.
- Grossnickle, David M.; Polly, P. David (22 November 2013). "Mammal disparity decreases during the Cretaceous angiosperm radiation". Proceedings of the Royal Society B: Biological Sciences. 280 (1771): 20132110. doi:10.1098/rspb.2013.2110. ISSN 0962-8452. PMC 3790494. PMID 24089340.
- Asar, Yasmin; Ho, Simon Y.W.; Sauquet, Hervé (11 May 2022). "Early diversifications of angiosperms and their insect pollinators: were they unlinked?". Trends in Plant Science. 27 (9): 858–869. Bibcode:2022TPS....27..858A. doi:10.1016/j.tplants.2022.04.004. PMID 35568622. Retrieved 30 June 2024.
- Hu, Shusheng; Dilcher, David L.; Jarzen, David M.; Winship Taylor, David (8 January 2008). "Early steps of angiosperm–pollinator coevolution". Proceedings of the National Academy of Sciences of the United States of America. 105 (1): 240–245. Bibcode:2008PNAS..105..240H. doi:10.1073/pnas.0707989105. ISSN 0027-8424. PMC 2224194. PMID 18172206.
- Tihelka, Erik; Cai, Chenyang; Giacomelli, Mattia; Pisani, Davide; Donoghue, Philip C. J. (11 November 2020). "Integrated phylogenomic and fossil evidence of stick and leaf insects (Phasmatodea) reveal a Permian–Triassic co-origination with insectivores". Royal Society Open Science. 7 (11): 201689. Bibcode:2020RSOS....701689T. doi:10.1098/rsos.201689. PMC 7735357. PMID 33391817.
- Jouault, Corentin; Condamine, Fabien L.; Legendre, Frédéric; Perrichot, Vincent (11 March 2024). "The Angiosperm Terrestrial Revolution buffered ants against extinction". Proceedings of the National Academy of Sciences of the United States of America. 121 (13): e2317795121. Bibcode:2024PNAS..12117795J. doi:10.1073/pnas.2317795121. ISSN 0027-8424. PMC 10990090. PMID 38466878.
- Cardinal, S.; Straka, J.; Danforth, B. N. (2010). "Comprehensive phylogeny of apid bees reveals the evolutionary origins and antiquity of cleptoparasitism". Proceedings of the National Academy of Sciences of the United States of America. 107 (37): 16207–11. Bibcode:2010PNAS..10716207C. doi:10.1073/pnas.1006299107. PMC 2941306. PMID 20805492.
- Peñalver, Enrique; Arillo, Antonio; Pérez-de la Fuente, Ricardo; Riccio, Mark L.; Delclòs, Xavier; Barrón, Eduardo; Grimaldi, David A. (9 July 2015). "Long-Proboscid Flies as Pollinators of Cretaceous Gymnosperms". Current Biology. 25 (14): 1917–1923. Bibcode:2015CBio...25.1917P. doi:10.1016/j.cub.2015.05.062. PMID 26166781. Retrieved 20 May 2024.
- Zhang, Qingqing; Wang, Bo (24 April 2017). "Evolution of Lower Brachyceran Flies (Diptera) and Their Adaptive Radiation with Angiosperms". Frontiers in Plant Science. 8: 631. doi:10.3389/fpls.2017.00631. ISSN 1664-462X. PMC 5401883. PMID 28484485.
- Bao, Tong; Wang, Bo; Li, Jianguo; Dilcher, David (3 December 2019). "Pollination of Cretaceous flowers". Proceedings of the National Academy of Sciences of the United States of America. 116 (49): 24707–24711. Bibcode:2019PNAS..11624707B. doi:10.1073/pnas.1916186116. ISSN 0027-8424. PMC 6900596. PMID 31712419.
- Tihelka, Erik; Li, Liqin; Fu, Yanzhe; Su, Yitong; Huang, Diying; Cai, Chenyang (12 April 2021). "Angiosperm pollinivory in a Cretaceous beetle". Nature Plants. 7 (4): 445–451. Bibcode:2021NatPl...7..445T. doi:10.1038/s41477-021-00893-2. ISSN 2055-0278. PMID 33846595. Retrieved 20 May 2024.
- Pellmyr, Olle (February 1992). "Evolution of insect pollination and angiosperm diversification". Trends in Ecology & Evolution. 7 (2): 46–49. Bibcode:1992TEcoE...7...46P. doi:10.1016/0169-5347(92)90105-K. PMID 21235949. Retrieved 20 May 2024.
- Schneider, Harald (28 January 2016). "The ghost of the Cretaceous terrestrial revolution in the evolution of fern–sawfly associations". Journal of Systematics and Evolution. 54 (2): 93–103. doi:10.1111/jse.12194. ISSN 1674-4918. Retrieved 11 May 2024 – via Wiley Online Library.
- ^ Lu, Xiu-Mei; Zhang, Wei-Wei; Liu, Xing-Yue (5 May 2016). "New long-proboscid lacewings of the mid-Cretaceous provide insights into ancient plant-pollinator interactions". Scientific Reports. 6 (1): 25382. Bibcode:2016NatSR...625382L. doi:10.1038/srep25382. ISSN 2045-2322. PMC 4857652. PMID 27149436.
- Li, Xin-Ran; Huang, Di-Ying (29 March 2023). "Atypical 'long-tailed' cockroaches arose during Cretaceous in response to angiosperm terrestrial revolution". PeerJ. 11: e15067. doi:10.7717/peerj.15067. ISSN 2167-8359. PMC 10066690. PMID 37013144.
- Boyce, C. Kevin; Lee, Jung-Eun (1 June 2011). "Could Land Plant Evolution Have Fed the Marine Revolution?". Paleontological Research. 15 (2): 100–105. doi:10.2517/1342-8144-15.2.100. ISSN 1342-8144. Retrieved 29 September 2023.
- Vermeij, Geerat J.; Grosberg, Richard K. (2 July 2010). "The Great Divergence: When Did Diversity on Land Exceed That in the Sea?". Integrative and Comparative Biology. 50 (4): 675–682. doi:10.1093/icb/icq078. PMID 21558232. Retrieved 1 October 2022.