rośliny-i-grzyby: Extinction event

Evidence: 100 • authority: 72

An extinction event (also known as a mass extinction or biotic crisis) is a widespread and rapid decrease in the biodiversity on Earth. Such an event is identified by a sharp fall in the diversity and abundance of multicellular organisms. It occurs when the rate of extinction increases with respect to the background extinction rate and the rate of speciation. Estimates of the number of major mass extinctions in the last 540 million years range from as few as five to more than twenty. These differences stem from disagreement as to what constitutes a "major" extinction event, and the data chosen to measure past diversity.

Evidence: 45 • authority: 72

Extinction is the termination of a species via the death of its last member. A taxon may become functionally extinct before the death of its last member if it loses the capacity to reproduce and recover. As a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. Over five billion species are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryotes globally, possibly many times more if prokaryotes a…

Evidence: 45 • authority: 72

The Late Devonian mass extinction, also known as the Kellwasser event, was a mass extinction event which occurred around 372.15 million years ago, at the boundary between the Frasnian and Famennian ages of the Late Devonian period. It is placed as one of the "Big Five" most severe mass extinction events in Earth's history, with likely around 40% of marine species going extinct, though the degree of severity is contested. A second mass extinction called the Hangenberg event, also known as the end-Devonian extinction, occurred 13 million years later around 358.86 million years ago, bringing an end to the Famennian and Devonian, as the world transitioned into the Carboniferous Period. The effe…

Evidence: 45 • authority: 72

The Late Ordovician mass extinction (LOME), sometimes referred to as the end-Ordovician mass extinction or the Ordovician–Silurian extinction, is the first of the "big five" major mass extinction events in Earth's history, occurring roughly 445 million years ago (Ma). It is often considered to be the second-largest-known extinction event, behind only the end-Permian mass extinction, in terms of the percentage of genera that became extinct. Extinction was global during this interval, eliminating 49–60% of marine genera and nearly 85% of marine species. Under most tabulations, only the Permian–Triassic mass extinction exceeds the Late Ordovician mass extinction in biodiversity loss. The extin…

Evidence: 41 • authority: 80

PHANEROZOIC PALEOTEMPERATURES: THE EARTH’S CHANGING CLIMATE DURING THE LAST 540 MILLION YEARS

Evidence: 30 • authority: 92

Application of a novel schema for describing fossil fern foliage and investigating taxonomic and morphological change across the Cretaceous-Paleogene boundary in western North America.. Premise The Chicxulub asteroid impact at the Cretaceous-Paleogene (K-Pg) boundary triggered a mass extinction 66 million years ago. Ferns thrived in the aftermath of the extinction, evidenced by the well-documented "fern spore spike." However, fern macrofossil records across the K-Pg boundary are less understood. Methods We analyzed 698 fern macrofossils from 19 Cretaceous and 83 Paleogene localities in the Raton (Colorado and New Mexico), Denver (Colorado), and Williston basins (North Dakota and Montana), g…

Evidence: 30 • authority: 72

The Cretaceous–Paleogene (K–Pg) extinction event, formerly known as the Cretaceous–Tertiary (K–T) extinction event, was a major mass extinction of three-quarters (75%) of the plant and animal species on Earth which occurred around 66 million years ago. The event caused the extinction of all the non-avian dinosaurs and most other tetrapods weighing more than 25 kg (55 lb), excepting some ectothermic species such as sea turtles and crocodilians. It marked the ends of both the Cretaceous period and the Mesozoic era, and logged the beginning of the current geological era, the Cenozoic era. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the K–Pg boundary or K…

Evidence: 22 • authority: 80

Ten Million Years of Mammal Extinctions in North America

Evidence: 22 • authority: 80

Ocean ecosystems take two million years to recover after mass extinction – new research

Evidence: 22 • authority: 80

Could asteroids bombard the Earth to cause a mass extinction in ten million years?

Evidence: 22 • authority: 80

More than 252 million years ago, mammal ancestors became warm-blooded to survive mass extinction

Evidence: 22 • authority: 80

Periodic impact cratering and extinction events over the last 260 million years