“The Cretaceous is the period when flowering plants (known as angiosperms) first evolved,” explained co-author Andrew Scott from the Department of Earth Sciences at Royal Holloway, University of London.
“It was also a time when there was a large number of fires, partly because there were probably higher atmospheric oxygen levels than there are today.”
Research suggested that oxygen made up about 25% or higher during this period, compared with 21% today.
“Angiosperms, particularly weedy angiosperms, can do particularly well in these sorts of circumstances; they can regenerate very fast and take advantage of such a regime,” Professor Scott told BBC News. ( read more )