Plant and insect diversification

I ask veteran plant-palaeontologist, Emeritus Professor John Anderson, to reflect on how the End Permian extinction event wrought profound changes in the plant diversity of the time. The fossil records show a complete change in the kinds of plants present before and after the End Permian event. ‘Like a teacher cleaning the blackboard’, the high rate of extinctions virtually created a complete new ecospace that was filled by the Dicroidium flora, which spread right across Gondwanaland.

The ‘ecospace’ which John refers to led to the radiation of insects (like beetles), the origins of mammals, the origins of dinosaurs and eventually of flowering plants. In Mid-Cretaceous, as flowering plants diversify, there was a co-evolution of the major orders of insects (especially the pollinators such as butterflies, moths, ants, wasps, and bees). John has shared these lovely insect and plant ‘timetrees’ from the magazine he was showing me:

• Biodiversity and Insect Timetree. John Anderson, Clarke Scholtz, Connal Eardley, Hannah Bonner (artist), Ditshego Madopi (layout), 2016. ‘Biodiversity & Extinction, Part 5: Insects’, Supernova, Vol. 5(3), Pretoria, RSA.

• Plant and Insect Timetree. Hannah Bonner (artist), Satu Jovero (production), John Anderson (scientist), 2018.

John raises his grave concerns about the current threat to pollinators and flowering plant species which resemble, in his eyes, a looming sixth extinction.