The Evolution of the Cretaceous Plants 

We do have evidence to show flowering plants in the late Cretaceous were pretty abundant but less than today reaching about a 50/50 diversity in south American flora Forests were generally much more open in the Cretaceous. Though more closed forests may have been present in North America suggesting the open forest structure may have been the consequence of sauropods seeing that they seem to have disappeared in North America prior to 67 Mya when Asian megafauna intrude into North America suggesting that Asia and North America were connected at this time probably due to the restructuring of land along the pacific via transform faulting and of course subduction, really complex geology but either way it suggests the two continents had briefly been connected via a land bridge around the time the Cretaceous came to a cataclysmic end. Unfortunately a number of gymnosperms particularly cycads and gingkoes really do seem to have declined during the Cretaceous at the same time as angiosperms exploded in diversity though it seems to have stabilized towards a roughly 50/50 mix. A talk based on North American late cretaceous flora mostly up in Canada (Alberta and Saskatchewan I think?) on the Royal Tyrrell museum channel seems to suggest a strong case for niche partitioning with gymnosperms being better adapted towards open sun i.e. canopy level flora and angiosperms predominately occupying the understory and ferns on the forest floor, there is still a modern analog of this type of ecosystem in the temperate rainforest of the Pacific northwest though it would have been much warmer than that more like the gulf coast. Forests were as a general rule it seems much more varied in their floral diversity in large part because the constant grazing of sauropods kept plants from taking over. Interestingly by the late Cretaceous gingkoes seem to have been effectively living fossils i.e. rare by that point in time having declined since their Jurassic heyday. Conifers were doing quite well though

I am not a paleobotanist, but I know something about this particular topic. And the answer is 'it depends'. By the Maastrichtian stage, the final 5 million years (+/-) of the Cretaceous Period, in many parts of the Northern Hemisphere Angiosperms were definitely dominant in overall diversity and in some habitats in total numbers of individual plants. Gymnosperms and ferns were still very important constituents of the flora in many biomes, but it is inarguable that they had undergone a significant decline in both species diversity and in their share of the vegetable biomass. Cycads saw an even more pronounced decline. It is simply not true that the Angiosperms needed the K-Pg extinction event to raise to dominance. Whatever effect that event had on the subsequent evolution of Earth's flora, the issue of dominance was already clear. Thats not to say the evolution and success of Gymnosperms and ferns was over by any means. Many forest types today are dominated by Gymnosperms and the ferns experienced a huge adaptive radiation in response to the expansion of tropical rainforests. If you are interested look up papers on the subject by Scott Wing, Kirk Johnson and Leo Hickey.

Yes sorry I've made a mistake, it's Weichselia

I did it last year, but I had copyright problems with Dougal Dixon..

@ Do you still have your After Man documentary saved in your files somewhere?

Retép Scávok yes, it really did, it was somewhen in Albian or Aptian (in the Early Cretaceous), maybe a few milion years earlier. But fossils of Poaceae (true grasses) are very rare in the cretaceous sediments (or metamorphic rocks). Paleontologists found only their seeds and pollen grain in some coprolites of herbivorous dinosaurs (or in their fossilized stomachs, for example in the fossilized stomach of the most complete dinosaur fossil… yeah, inside of Borealopelta markmitchelli). I read some sources that suggest that Poaceae diversified a little in the Cretaceous period, but were still rare as compared with recent. I also read somewhere else that their largest ecological expansion came allegedly in the Miocene period (around 16 - 11 milion years ago) and continues to recent.

@@Marasuchus216 thanks

@@szalard you’re welcome :)

True grasses were definitely present in the Cretaceous. That is not to imply they were a dominant component of the flora. Although in at least one Late Cretaceous paleoenvironment in Spain, Cattails (basal members of the Poales--the order which includes grasses) was a dominant member of the flora alongside Willows and Palms. The biggest news in this regard is the discovery of true grass phytoliths in the dentition and fossilized dung of dinosaurs going back to the late Early Cretaceous (113-101 million years ago). By the end of the Cretaceous in India at least 5 major clades of grasses were recovered from phytoliths found in the fossil dung of Titanosaurid Sauropods. That particular discovery blew the collective minds of the paleobotanical community.

My most boomer comments, thanks for your participation and thanks for the "kid" I'm flattered 😁

@. You do have interesting 🎥 and I would like to see them all the way thru. But that C.G.V. is like.... To me...someone dragging their fingernails down a chalkboard.

​@@tazkrebbeks3391wtf is cgv