Taxonomy term

reptile

Two ichthyosaurs become one

While dinosaurs ruled on land in the Mesozoic, dolphin-like marine reptiles called ichthyosaurs roamed the oceans. Paleontologists first described the genus in 1821 based on remains discovered in England, naming the first species Ichthyosaurus communis. The description of a second species, I. intermedius, followed in 1822. Although these two species were the earliest-known ichthyosaurs, they are also some of the most poorly understood, as their initial descriptions were based on limited remains.

22 Jun 2017

Hammerhead herbivore pioneered vegetarianism in Triassic seas

New fossils found in southern China hint that the earliest herbivorous marine reptiles got off to a bizarre start: Atopodentatus unicus, which lived about 244 million years ago and sported a unique hammerhead-like snout for grazing underwater plants, sheds light on how the earliest marine reptiles began experimenting with herbivory after the Permian mass extinction, which killed off 96 percent of marine organisms about 252 million years ago. This “Great Dying” event left vast holes in the ecology of the Early Triassic, and a diversity of new feeding styles evolved to occupy the open niches.

 
21 Sep 2016

Turtle finds lower Altiplano elevation estimate

Rare turtle fossils uncovered in Bolivia suggest that, about 13 million years ago, the southern portion of South America’s Altiplano — the arid, high-elevation plateau immediately west of the Andes — was far lower than previously thought.

29 Apr 2016

Inside an icthyosaur's brain

While the dinosaurs were busy ruling the continents in the Mesozoic, an order of marine reptiles known as the ichthyosaurs ruled the oceans. Ichthyosaurs are well known from numerous fossils, but they are often found flattened, limiting researchers’ ability to study the skulls and braincases as they existed in life.

01 Apr 2016

Unshelled ancestor fills big gap in turtle family tree

Turtles may seem like innocent creatures, but the uniquely shelled reptiles have long posed a problem for paleontologists. Shelled turtles are plentiful in the fossil record, but specimens of their intermediate forebears — the missing links between ancestral unshelled reptiles and modern turtles — have remained elusive. Now, a closer look at the skull of what may be one of the earliest turtle relatives is filling gaps in the turtle family tree.
 
28 Dec 2015

Oldest marine turtle found in Colombia

A 120-million-year-old sea turtle recently discovered in Colombia is about 25 million years older than the previously oldest-known marine turtle. Despite its age, the new 2-meter-long specimen is very similar to living marine turtles and was placed in the group Chelonioidea, which includes the modern Hawksbill turtle and green sea turtle.
 
28 Dec 2015

Snake forebear had two back legs but no front legs

The more than 3,400 species of snakes alive today may have descended from one ancestor that lacked forelimbs, but which had small vestigial hind limbs complete with ankle bones and toes, according to a new study published in BMC Evolutionary Biology.
 
30 Aug 2015

Ancient marine reptiles born alive and ready to hunt

Mosasaurs, giant marine reptiles found in all the world’s oceans during the Late Cretaceous, may have reached up to 18 meters in length, and they were fearsome predators. Little is known, however, about newborn, or neonate, mosasaurs because very few have been found. Now, new research describing a rare fossil find from Kansas reveals that mosasaurs likely gave birth to live young that were born swimming and able to survive alongside the adults.
 
23 Aug 2015

Early Triassic fossil showed live birth in action

An exceptional case of fossil preservation has provided the oldest view yet of the moment of live birth in a vertebrate. The fossil contains parts of four marine reptile individuals — a mother and her three young — from the ichthyopterygian genus, Chaohusaurus, and was unearthed in the Anhui Province of eastern China. While one of the young is still inside the mother and a second is already outside (and mostly obscured from view by other portions of the fossil), the third juvenile can be clearly seen emerging headfirst from the mother’s pelvis. Thought to be about 1 meter long when fully grown, Chaohusaurus lived about 248 million years ago in the Early Triassic and was an ancestor of later ichthyosaurs.

22 Jun 2014

Triassic Park: On the origin of (dinosaur) species

Ask a third grader what happened to the dinosaurs and she will tell you that an asteroid killed them all. Many adults even know what caused the demise of the dinosaurs: A massive bolide crashed into the Yucatán Peninsula in Mexico about 65 million years ago, setting in motion a series of environmental changes that killed off 60 percent of life on Earth. But if you ask people about the origin of dinosaurs 165 million years earlier, you get blank looks. Even many paleontologists have little to say about the subject.

18 Jan 2011