The origins and evolutionary relationships between the three main groups of amphibians are hotly debated. A molecular phylogeny based on rDNA analysis dating from 2005 suggests salamanders and caecilians are more closely related to each other than they are to frogs and the divergence of the three groups took place in the Paleozoic or early Mesozoic before the breakup of the supercontinent Pangaea and soon after their divergence from the lobe-finned fishes. This would help account for the relative scarcity of amphibian fossils from the period before the groups split. Read more ...
Paleontologists have identified fossil fragments of what are thought to be the oldest known frogs in North America. Science Daily - February 27, 2019
Prehistoric frogs in amber surface after 99 million years BBC - June 15, 2018
Frogs trapped in amber for 99 million years are giving a glimpse of a lost world. The tiny creatures have been preserved in sticky tree resin since the end of the Age of the Dinosaurs. The four fossils give a window into a world when frogs and toads were evolving in the rainforests. Amber from Myanmar, containing skin, scales, fur, feathers or even whole creatures, is regarded as a treasure trove by paleontologists.
'Frog-amander' Fossil Fills Evolutionary Gap Live Science - May 21, 2008
A frog-like creature with a stubby tail once paddled through a quiet pond in what is now Texas, snapping up mayflies while keeping an ear out for bellowing mates, new fossil evidence suggests. That was about 290 million years ago. This amphibian is from near to the point where frogs and salamanders first split.
70-million-year-old fossil of a giant frog has been unearthed in Madagascar BBC - February 19, 2008
A 70-million-year-old fossil of a giant frog has been unearthed in Madagascar by a team of UK and US scientists. The creature would have been the size of a "squashed beach ball" and weighed about 4kg (9lb), the researchers said. They added that the fossil, nicknamed Beelzebufo or "frog from hell", was "strikingly different" from present-day frogs found on the island nation.
Giant "Frog From Hell" Fossil Found in Madagascar National Geographic - February 19, 2008
A 70-million-year-old fossil of a giant frog has been unearthed in Madagascar by a team of UK and US scientists. The creature would have been the size of a "squashed beach ball" and weighed about 4kg (9 lb), the researchers said. They added that the fossil, nicknamed Beelzebufo or "frog from hell", was "strikingly different" from present-day frogs found on the island nation. The researchers added that the discovery of the fossil supported the theory that Madagascar and the Indian and South American land masses could have been linked until the Late Cretaceous Period (75-65 million years ago).
Ancient Frog could be 25M years old National Geographic - February 15, 2007
A miner from Mexico's Chiapas state has made the find of a lifetime a tiny tree frog preserved in amber that could be 25 million years old, a scientist recently announced . The block of amber, or fossilized tree resin, encasing the 0.4-inch (1-centimeter) frog was unearthed in 2005 and sold to a private collector, according to the Associated Press (AP). The collector then lent the piece seen in this photo released on February 14 to scientists. The specimen appears to belong to the genus Craugastor, said Gerardo Carbot, of the Chiapas Natural History and Ecology Institute, who has been studying the find. This genus includes many modern frogs native to Central America.
Fossil frogs yield 'soft tissues' BBC - July 26, 2006
Scientists have extracted marrow from the bones of frogs and salamanders that died 10 million years ago in the muddy swamps of north-eastern Spain. The first fossilized bone marrow known to science provides a rare insight into the make-up of prehistoric animals. It is preserved in remarkable detail; usually only hard tissue such as bone survives in the fossil record. The soft tissue may yield traces of protein and DNA, researchers report in the journal Geology. Bone marrow is the tissue that fills the centre of large bones, acting as a factory for producing new platelets and red and white blood cells.
ANCIENT AND LOST CIVILIZATIONS
PHYSICAL SCIENCES INDEX
ALPHABETICAL INDEX OF ALL FILES
CRYSTALINKS HOME PAGE
PSYCHIC READING WITH ELLIE
2012 THE ALCHEMY OF TIME