Extinction events Archives

Home Biology Evolution Home Biology Paleontology & Fossils July 31, 2024 Editors' notes Mass extinction 66 million years ago triggered rapid evolution of bird genomes, study finds by University of Michigan Photograph of a Broad-billed Tody, Todus subulatus, a member of the bird group Coraciimorphae.

Biogeochemical Cycles & Geobiology, Extinction events, Genomics, Proteomics, Bioinformatics, Impact events, Nomenclature, Systematics, Natural History, Press Release

Mass Extinction 66 million Years Ago Triggered Rapid Evolution Of Bird Genomes

by Keith CowingAugust 1, 2024August 1, 2024

Shortly after an asteroid slammed into Earth 66 million years ago, life for non-avian dinosaurs ended, but the evolutionary story for the early ancestors of birds began.

AI-generated image of what the ocean may have looked like during the Paleozoic era, around 500 million years ago. -- Syracuse University

Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Fossils & Paleontology, Gaia - Planetary Perspectives, Habitable Zones, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography

Scientists Untangle Interactions Between Earth’s Early Life Forms And The Environment Over 500 Million Years

by Keith CowingJuly 30, 2024July 30, 2024

The atmosphere, the ocean and life on Earth interacted over the past 500-plus million years in ways that improved conditions for early organisms to thrive. Now, an interdisciplinary team of […]

A quarry illustrating bands of stratified limestone from the ancient seafloor in what is now Mercato San Severino in Italy. Credit: Courtesy of F. Tissot

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Fossils & Paleontology, Gaia - Planetary Perspectives, Mapping, Geodesy, Cartography, Bathymetry, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography

Sediments Reveal The Ancient Ocean During a Mass Extinction Event

by Keith CowingJuly 15, 2024July 7, 2024

About 183 million years ago, volcanic activity in modern South Africa unleashed an estimated 20,500 gigatons of carbon dioxide (CO2) into the ocean-atmosphere system over a period of 300 to […]

Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Fossils & Paleontology, Gaia - Planetary Perspectives, Press Release

Ocean’s Loss of Oxygen Caused Massive Jurassic Extinction. Could it Happen Again?

by Keith CowingJune 27, 2024June 27, 2024

Researchers have discovered a clue in Italian limestone that helps explain a mass extinction of marine life millions of years ago, and may provide warnings about how oxygen depletion and […]

Adaptation to the harsh conditions of a geologic period of global glaciation may have sparked the development of multicellular life. (image: Michael Schiffer/Unsplash)

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Cryobiology, Extinction events, Genomics, Proteomics, Bioinformatics, Habitable Zones, Icy Worlds, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography

Why The Harsh Snowball Earth Kick-started Our Earliest Multicellular Ancestors

by Keith CowingJune 27, 2024June 27, 2024

For a billion years, single-celled eukaryotes ruled the planet. Then around 700 million years ago during Snowball Earth — a geologic era when glaciers may have stretched as far as […]

Ammonites basking under the Late Cretaceous sun. CREDIT Callum Pursall (@cpursall on X)

Extinction events, Fossils & Paleontology, Gaia - Planetary Perspectives, Impact events, Press Release

Ammonites’ Fate Sealed By The Meteor Impact That Wiped Out The Dinosaurs

by Keith CowingJune 27, 2024June 27, 2024

Ammonites were not in decline before their extinction, scientists have found.

Ratio of the cumulative collision rate of comets with the Earth analog to the cumulative collision rate of carbonaceous asteroids with the Earth analog. The cumulative collision rates are reset at the time of the Moon-forming impact; and the ratio is set to 0 when the cumulative collision rates of carbonaceous asteroids (denominator) equals 0. So the dashed line shows the number of collisions with comets relative to the number of collisions with carbonaceous asteroids (weighted by their respective numbers in our simulations) on Earth since gas disk dispersal until the Moon-forming impact; and the solid line shows the same relative number since the Moon-forming impact until the end of the simulation. While cumulative collision rates of comets with Earth are ≃ 4 orders of magnitude smaller than those of carbonaceous asteroids before the Moon-forming impact, they are between 3 and 7 orders of magnitude smaller after the Moon-forming impact. In 30% of our simulations, there is about 1 comet every 103 carbonaceous asteroids colliding with the Earth after the Moon-forming event, which is consistent with the total cometary mass expected during late accretion. -- astro-ph.EP

Astrochemistry, Astrogeology, Biogeochemical Cycles & Geobiology, Comets and Asteroids, Extinction events, Gaia - Planetary Perspectives, Habitable Zones, Impact events, Meteorites & Asteroids, Moon, Origin & Evolution of Life, Status Report, Water/Hycean Worlds & Oceanography

Crash Chronicles: Relative Contribution From Comets and Carbonaceous Asteroids to Earth’s Volatile Budget In The Context of an Early Instability

by Keith CowingJune 25, 2024June 25, 2024

Recent models of solar system formation suggest that a dynamical instability among the giant planets happened within the first 100 Myr after disk dispersal, perhaps before the Moon-forming impact. As […]

On June 12, 2009, a fortuitous orbit of the International Space Station (ISS) made it possible for an astronaut on board to capture Sarychev Volcano in the early stages of eruption. The volcano is located on the northwestern end of Matua Island, which is part of the Kuril Islands, a chain of 56 islands northeast of Japan. Larger image -- NASA

Biogeochemical Cycles & Geobiology, Biophysics, Biosignatures & Paleobiology, Extinction events, Microbiology & Virology, Status Report

Carboxydovores From The Pseudomonadota Colonise Volcanic Soils During Succession

by Keith CowingJune 24, 2024June 24, 2024

Carbon monoxide (CO) degrading microorganisms are present in volcanic deposits throughout succession, with vegetation and soil influencing the communities present. The carboxydovores are a subset of CO degraders that use […]

Earth's oceans as seen by STS-114 -- NASA

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Biosignatures & Paleobiology, Extinction events, Gaia - Planetary Perspectives, Habitable Zones, Origin & Evolution of Life, Press Release, Water/Hycean Worlds & Oceanography

Self-propelling Oxygen Decline In Earth’s Ancient Oceans

by Keith CowingJune 22, 2024June 22, 2024

Scientists from the University of Copenhagen have made significant strides in understanding ancient ocean anoxia, with potential insights for today’s marine environments.

Spatial patterns in cGENIE DIC δ13C excursion size and water mass age in response to −1‰ CIE. (A) Relative size of the δ13C excursion recorded for each model grid relative to the mean δ13C excursion in the ocean layer centered at ~3,300 m water depth. δ13C excursions are calculated as the DIC δ13C value at 11 ky less the initial value in that grid. Red colors (more negative) indicate CIEs larger than the average. (B) Atlantic zonal mean size of the δ13C excursion relative to the atmospheric δ13C excursion. δ13C excursions are calculated as the DIC δ13C value at 11 ky less the initial value. Contours show the Atlantic Meridional Overturning streamfunction at 11 ky calculated using the mask in SI Appendix, Fig. S1 (for comparison to the global streamfunction, see SI Appendix, Fig. S2). (C) Relative size of the change in water mass age recorded for each model grid relative to the mean change in water mass age in the ocean layer centered at ~3,300 m water depth. Changes in water mass age are calculated as the water mass age at 11 ky less the initial age in that grid. Red colors indicate larger increases in water mass age than the global average. -- PNAS

Atmospheres, Climate, Weather, Biogeochemical Cycles & Geobiology, Extinction events, Gaia - Planetary Perspectives, Habitable Zones, Press Release, Water/Hycean Worlds & Oceanography

Ancient Ocean Slowdown Warns Of Future Climate Chaos On Earth

by Keith CowingJune 13, 2024June 13, 2024

When it comes to the ocean’s response to global warming, we’re not in entirely uncharted waters. A UC Riverside study shows that episodes of extreme heat in Earth’s past caused […]