Tag Archive for 'Amniota'

The 355-million-year-old track-bearing slab from the Snowy Plains Formation, Australia. Image credit: Long et al., doi: 10.1038/s41586-025-08884-5.

Fossil Tracks Found in Australia Push Back Origin of Reptiles by 35 Million Years

May 15, 2025 by News Staff

Paleontologists have discovered fossilized tracks of a reptile-like animal — securely dated to the early Tournaisian age of the Carboniferous period,...

Life restoration of Lalieudorhynchus gandi and an associated aquatic tupilakosaurid temnospondyl (bottom left); estimated water depth about 2 m, algae are possible. Image credit: Frederik Spindler.

Permian Synapsid Had Hippopotamus-Like Semi-Aquatic Lifestyle

Aug 4, 2022 by Enrico de Lazaro

A new genus and species of caseid synapsid that lived 264 million years ago (Permian period) has been identified from a partial but well-preserved postcranial...

Field photograph of the pathologic ovum-in-ovo egg documented from the Lameta Formation of village Padlya, Dhar District, Madhya Pradesh, India. Two slightly partially broken circular eggshell outlines can be seen with broken eggshell fragments within. A crescent-shaped gap is characteristically present in the upper right part of the egg. Image credit: Dhiman et al., doi: 10.1038/s41598-022-13257-3.

Unique Titanosaur Egg-Inside-Egg Found in India

Jun 22, 2022 by Enrico de Lazaro

Paleontologists have found a fossilized egg within another egg — a condition known as ovum-in-ovo — of a titanosaurid dinosaur in central India....

This artist’s impression shows a long umbilical scar on Psittacosaurus. Image credit: Jagged Fang Designs.

Some Non-Avian Dinosaurs Had ‘Belly Buttons,’ New Fossil Shows

Jun 13, 2022 by News Staff

In egg-laying amniotes (reptiles, birds and monotremes), the developing embryo is tethered to a number of the extraembryonic membranes that deliver oxygen...

Central bearded dragon cells under a microscope, showing the tiny microchromosomes huddled together amongst the larger chromosomes. Image credit: Shayer Alam / La Trobe University.

‘Microchromosomes’ are Fundamental Building Blocks of Amniote Chromosomes, Study Finds

Nov 2, 2021 by News Staff

Tiny ‘microchromosomes’ (<0.5 µm) are the building blocks of all animal genomes, but they underwent ‘dizzying rearrangement’ in mammals, including...

Brookesia nana, male. Image credit: Glaw et al., doi: 10.1038/s41598-020-80955-1.

World’s Tiniest Reptile Found in Madagascar

Feb 1, 2021 by Natali Anderson

An international team of scientists has discovered a new, extremely miniaturized species of the chameleon genus Brookesia living in a montane rainforest...

Xu et al. present the first anatomical and histological evidence of tail repair with regrowth in an archosaur, the American alligator (Alligator mississippiensis); the regrown alligator tails constituted approximately 6-18% of the total body length and were morphologically distinct from original tail segments. Image credit: Norbert Nagel / CC BY-SA 3.0.

Young American Alligators Can Regrow Their Tails, Study Shows

Nov 24, 2020 by News Staff

Young American alligators (Alligator mississippiensis) have the ability to regrow their tails up to 18% of their total body length, according to a study...

The central bearded dragon (Pogona vitticeps). Image credit: George Chernilevsky.

Bearded Dragons Share Sleep Patterns with Mammals, Study Reveals

Apr 29, 2016 by News Staff

A new study led by Dr. Gilles Laurent from the Max Planck Institute for Brain Research in Frankfurt, Germany, reveals slow-wave (SW) and rapid eye movement...