By the start of the Triassic, all the Earth's landmasses had ... The oceans teemed with the coiled-shelled ammonites, mollusks, and sea urchins that survived the Permian extinction and were ...

Based on the fossil record, ammonites came in a wide range of sizes and shapes, from smaller than an inch to as large as nine feet wide. Some ammonites had long, straight shells, while others had ...

Like Shastasaurus, the Shasta Lake ammonites lived during the Triassic Period, about 231 million years ago, Summers said. Paleontologists have found other Triassic Period fossils throughout Shasta ...

Global warming triggered by heavy volcanic activity is hypothesized by some scientists to have caused the end-Triassic extinction event that obliterated up to 80 percent of Earth’s species. These ...

Fossils found in the northern part of Hokkaido are a new type of ammonite, the once-ubiquitous spiral-shelled creatures that went extinct with the dinosaurs 65 million years ago, researchers said.

The Triassic period, spanning 252 to 201 million years ago, was crucial for the evolution of terrestrial tetrapods, including early dinosaurs, mammalian ancestors, and crocodile relatives.

The Triassic Period was a time of great change. Bookended by extinctions, this era saw huge shifts in the diversity and dominance of life on Earth, ushering in the appearance of many well-known groups ...

Koichi Fukuoka’s career as a copperplate engraver took an unexpected turn after he encountered fossils of ammonites, a spiral-shelled creature that lived in the age of the dinosaurs. The artist ...

The Triassic period stands out in Earth’s history as the time when dinosaurs first evolved. It was followed by the Jurassic and Cretaceous periods – at the end of the latter, the dinosaurs ...