Tyrannosaurus rex size compared too many fish dating site tinder online dating australia services
Based on marine fossils, it is estimated that 75% or more of all species were made extinct by the K–Pg extinction event.The event appears to have affected all continents at the same time.Approximately 46% of diatom species survived the transition from the Cretaceous to the Upper Paleocene.This suggests a significant turnover in species, but not a catastrophic extinction of diatoms, across the K–Pg boundary.Similar, but more complex patterns have been found in the oceans.Extinction was more severe among animals living in the water column than among animals living on or in the sea floor.This plant extinction caused a major reshuffling of the dominant plant groups.Omnivores, insectivores, and carrion-eaters survived the extinction event, perhaps because of the increased availability of their food sources.
These characteristics have been linked to crocodilian survival at the end of the Cretaceous.
Scientists hypothesize that these organisms survived the collapse of plant-based food chains because they fed on detritus (non-living organic material).
In stream communities, few animal groups became extinct because such communities rely less directly on food from living plants and more on detritus that washes in from the land, buffering them from extinction.
Non-avian dinosaurs, for example, are known from the Maastrichtian of North America, Europe, Asia, Africa, South America, and Antarctica, Even though the boundary event was severe, there was significant variability in the rate of extinction between and within different clades.
Species that depended on photosynthesis declined or became extinct as atmospheric particles blocked sunlight and reduced the solar energy reaching the surface of the Earth.