Zitteliana online dating, cretaceous–Paleogene extinction event
Cretaceous–Paleogene extinction event
It contradicts the article on sharks, and self-contradicts. As the marine microbiota recovered, however, does seeing each other mean dating it is thought that increased speciation of benthic foraminifera resulted from the increase in food sources.
In addition, it is postulated that some early monotremes, marsupials, and placentals were semiaquatic or burrowing, as there are multiple mammalian lineages with such habits today. Once the atmosphere cleared, photosynthetic organisms, initially ferns and other ground-level plants, returned.
Species that depended on photosynthesis declined or became extinct as atmospheric particles blocked sunlight and reduced the solar energy reaching the ground. In particular, metatherians largely disappeared from North America, and the Asian deltatheroidans became extinct aside from the lineage leadng to Gurbanodelta.
Diversification of mammals stalled across the boundary. However, these fossil beds are geographically limited, covering only part of one continent. Similarly, fossil pollen shows devastation of the plant communities in areas as far apart as New Mexico, Alaska, China, and New Zealand.
The absence of these birds in the Paleogene is evidence that a mass extinction of archaic birds took place there. These large pterosaurs were the last representatives of a declining group that contained ten families during the mid-Cretaceous. These characteristics have been linked to crocodilian survival at the end of the Cretaceous.
While the deep sea realm was able to remain seemingly unaffected, there was an equal loss between the open marine apex predators and the durophagous demersal feeders on the continental shelf. The apparent rate is influenced by a lack of fossil records, rather than extinctions. It is thought that all non- avian theropods became extinct, including then-flourishing groups such as enantiornithines and hesperornithiforms.
The paragraph on sharks and survival through the K-T event simply does not make sense. Not only did the climate temperature increase, but the water temperature decreased, causing a drastic decrease in marine diversity. This is reminiscent of areas blighted by modern volcanic eruptions, where the recovery is led by ferns, which are later replaced by larger angiosperm plants. Additionally, all six turtle families in existence at the end of the Cretaceous survived into the Paleogene and are represented by living species.
It also requires some language cleanup. It does not represent all marine species, just those that are readily fossilized. The dominance of fungal species lasted only a few years while the atmosphere cleared and plenty of organic matter to feed on was present.
This plant extinction caused a major reshuffling of the dominant plant groups. Ultimate recovery of the benthic populations occurred over several stages lasting several hundred thousand years into the early Paleocene.
No purely herbivorous or carnivorous mammals seem to have survived. Other scientists have made the same assessment following their research.