Showing 20 articles starting at article 601
Categories: Offbeat: Earth and Climate, Paleontology: Fossils
Published DNA sequence enhances understanding origins of jaws
(via sciencedaily.com) Researchers have discovered and characterized a DNA sequence found in jawed vertebrates, such as sharks and humans, but absent in jawless vertebrates, such as lampreys. This DNA is important for the shaping of the joint surfaces during embryo development.
Published Ancient superpredator got big by front-loading its growth in its youth
(via sciencedaily.com) Original source Whatcheeria, a six-foot-long salamander-like creature that lived 340 million years ago, was the T. rex of its time: the biggest, baddest predator in its habitat. A new study reveals how they grew to their 'giant' size: instead of growing slow and steady throughout their lives like many modern reptiles and amphibians, they did most of their growing when they were young.
Published 525-million-year-old fossil defies textbook explanation for brain evolution
(via sciencedaily.com) According to a new study, fossils of a tiny sea creature with a delicately preserved nervous system solve a century-old debate over how the brain evolved in arthropods, the most species-rich group in the animal kingdom. Combining detailed anatomical studies of the fossilized nervous system with analyses of gene expression patterns in living descendants, they conclude that a shared blueprint of brain organization has been maintained from the Cambrian until today.
Published Decrease in crucial trace element preceded ancient mass extinction
(via sciencedaily.com) A decline in the element molybdenum across the planet's oceans preceded a significant extinction event approximately 183 million years ago, new research shows.
Published World's oldest meal helps unravel mystery of our earliest animal ancestors
(via sciencedaily.com) The contents of the last meal consumed by the earliest animals known to inhabit Earth more than 550 million years ago has unearthed new clues about the physiology of our earliest animal ancestors, according to scientists.
Published Earth might be experiencing 7th mass extinction, not 6th
(via sciencedaily.com) Earth is currently in the midst of a mass extinction, losing thousands of species each year. New research suggests environmental changes caused the first such event in history, which occurred millions of years earlier than scientists previously realized.
Published 1,700-year-old spider monkey remains discovered in Teotihuacán, Mexico
(via sciencedaily.com) Original source The complete skeletal remains of a spider monkey -- seen as an exotic curiosity in pre-Hispanic Mexico -- grants researchers new evidence regarding social-political ties between two ancient powerhouses: Teotihuacán and Maya Indigenous rulers. The remains of other animals were also discovered, as well as thousands of Maya-style mural fragments and over 14,000 ceramic sherds from a grand feast. These pieces are more than 1,700 years old.
Published Solid salamander: Prehistoric amphibian was as heavy as a pygmy hippo
(via sciencedaily.com) Scientists have calculated the body mass of two ancient amphibians.
Published Rapid fluctuations in oxygen levels coincided with Earth's first mass extinction
(via sciencedaily.com) Rapid changes in marine oxygen levels may have played a significant role in driving Earth's first mass extinction, according to a new study.
Published Ray-finned fish survived mass extinction event
(via sciencedaily.com) Ray-finned fish, now the most diverse group of backboned animals, were not as hard hit by a mass extinction event 360 million years ago as scientists previously thought.
Published Tiniest ever ancient seawater pockets revealed
(via sciencedaily.com) Ancient seawater pockets offer a new source of clues to climate change in vanished oceans and our own.
Published Earth can regulate its own temperature over millennia, new study finds
(via sciencedaily.com) A new study confirms that the planet harbors a 'stabilizing feedback' mechanism that acts over hundreds of thousands of years to keep global temperatures within a steady, habitable range.
Published Exploring the possibility of extraterrestrial life living in caves
(via sciencedaily.com) For millennia, caves have served as shelters for prehistoric humans. Caves have also intrigued scholars from early Chinese naturalists to Charles Darwin. A cave ecologist has been in and out of these subterranean ecosystems, examining the unique life forms -- and unique living conditions -- that exist in Earth's many caves. But what does that suggest about caves on other planetary bodies? In two connected studies, engineers, astrophysicists, astrobiologists and astronauts lay out the research that needs to be done to get us closer to answering the old-age question about life beyond Earth.
Published Footprints claimed as evidence of ice age humans in North America need better dating, new research shows
(via sciencedaily.com) The preserved footprints found in New Mexico's Lake Otero Basin would upend scientific understanding of how, and when, humans first arrived in North America, if they are accurately dated. A new study brings the age claim into question.
Published Welsh 'weird wonder' fossils add piece to puzzle of arthropod evolution
(via sciencedaily.com) Original source International team of researchers describe new fossil species discovered in fossil deposit near Llandrindod Wells in mid-Wales. The fossil, Mierridduryn bonniae, shares many features with Cambrian 'weird wonder' Opabinia, but is 40 million years younger. Robust phylogenetic analyses suggest that Mierridduryn is either the third opabiniid ever discovered, or is a distinct group that is key for understanding the evolution of the arthropod head.