PALEO

paleo

An asteroid redirected bird evolution

When an asteroid hit Earth 66 million years ago, it helped wipe out all the dinosaur lineages save one: the birds. But birds didn’t completely dodge the cataclysm the asteroid triggered. Recent research suggests that forests around the planet were devastated. With forests gone, bird species that called trees home went extinct alongside their nonavian dinosaur cousins. This means that the birds that we see living in trees today evolved from lineages that, in the aftermath of the impact, were ground-dwelling.

30 Aug 2018

Grazing gave elephant ancestors an edge

The poor dental hygiene of some ancient elephant-like beasts has proven a boon to future scientists. In a new study, researchers used grass fragments recovered from the teeth of two extinct species of Central Asian gomphotheriids to decode the animals’ feeding habits during the middle Miocene.

24 Aug 2018

Geomedia: Books: Informative and inspiring: "Why Dinosaurs Matter"

In his new book, “Why Dinosaurs Matter,” vertebrate paleontologist Kenneth Lacovara aims to explain why, in fact, studying ancient life does matter. Lacovara has spent his career excavating and publishing on dinosaurs and paleoenvironments, as well as communicating the wonders of paleontology. To share this passion, Lacovara founded Edelman Fossil Park at Rowan University in New Jersey, a publicly accessible quarry containing vertebrate and invertebrate fossils from the Cretaceous-Paleogene boundary, roughly 66 million years ago.

21 Aug 2018

Down to Earth With: Paleobiologist Rowan Lockwood

In 1608, Captain John Smith noted that oysters “lay as thick as stones” on the floor of the Chesapeake Bay. The shell reefs — built up by hundreds of years of oyster generations — were so large, ships wrecked against them. And each oyster was so massive, to eat one, you had to cut it into pieces — like a steak.

27 Jul 2018

Island-dwelling mammal had small brain, keen senses

A host of fossils has been discovered near the Romanian town of Haţeg, including 15 species of Late Cretaceous dinosaurs — some of them dwarf dinosaurs — and enormous pterosaurs with 12-meter wingspans, prompting the establishment of the Haţeg Country Dinosaurs Geopark in 2005.

26 Jul 2018

Diamonds and the Eocene climate of the Bell River Basin

Diamonds mined from the kimberlite pipes of the Lac de Gras diamond field in Northwest Territories, Canada, are among the world’s youngest known diamonds, dating from 75 million to 45 million years ago. In some cases, when the magmas that carried these diamonds to Earth’s surface encountered water-saturated rock at shallow depths, violent steam explosions called phreatomagmatic eruptions resulted. Such explosions can form volcanic craters known as maars, which often fill with water and accumulate lake sediment, along with soil and vegetation that collapse into them from their margins. In the case of the Panda kimberlite pipe at the Ekati Mine in the Lac de Gras area, maar sediments accumulated far below the surrounding terrain, such that they were later buried under glacial deposits rather than being eroded away by ice sheets during the past million years. Wood and other organic materials were entombed and preserved in their natural state, thereby preserving shreds of the Paleo-Bell River Basin.

25 Jul 2018

Saglek Basin sediments suggest a Grand Canyon connection

Pollen makes an ideal fossil. Pollen grains — each only a few tens of microns in diameter — are produced in astronomical quantities by plants and record information about the ecosystem from which they came, thus providing a way to reconstruct past environments. Additionally, pollen is composed of a highly stable organic substance, sporopollenin, which resists decay as well as the high heat and pressure associated with deep burial, lithification and tectonism. It is so resistant, in fact, that it can be eroded from rock and recycled into younger sediments, a process recognized in the 1980s by V. Eileen Williams of the University of British Columbia in her studies of Paleo-Bell River sediments deposited in the Labrador Sea.

25 Jul 2018

The Paleo-Bell River: North America's vanished Amazon

With similar geologic and tectonic histories, including a continuous mountain cordillera along their western margins, why does South America have a massive river draining a continentwide basin but North America does not? Before the Pleistocene, it did.
25 Jul 2018

Mineral clue to finding perfectly preserved fossils?

The exquisitely preserved fossils found in the 500-million-year-old Burgess Shale in Canada are famous for the detailed anatomy they display. They also provide a rare and crucial record of the Cambrian Explosion, when most of the major animal groups first appeared.

17 Jul 2018

Pterosaurs flew into the Late Cretaceous

Late Cretaceous skies might have been more crowded than previously thought. Until recently, scientists thought the dearth of pterosaur fossils found from the Late Cretaceous meant that the flying reptiles were in decline before the catastrophic end of the Mesozoic. But the recent discovery in Morocco of several new pterosaur species suggests this unique branch of reptiles may have been thriving just before the end-Cretaceous extinction.

04 Jul 2018

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