IT has brought dinosaurs trampling and roaming the salons of millions of viewers. Now, 25 years after the first broadcast of the series, a new one, updated Walking with dinosaurs is back on the BBC this weekend.
In the years that followed, science has not been motionless. About 50 species have been discovered each year since 1999 and the advent of powerful imaging techniques and digital reconstruction have led to major progress in our understanding of what dinosaurs looked like and how they lived. Here are some of the biggest developments.
Feathered dinosaurs
In the 1990s, a handful of feather dinosaurs fossils had been identified, but they were not well preserved and their wider meaning remained clear.
“The public was not ready for that,” said Dr. Dave Hone, paleontologist at Queen Mary, University of London. “Now, we are to the point where we have dozens of feathered species definitely a hundred more when we are very convinced that they had feathers because all their parents do. This pushes feathers in the family tree, which is a fairly important change.”
The feathers count, not only in terms of appearance, but they added weight to the argument that certain dinosaurs were with hot blood and shape our understanding of the behavior and the evolution of dinosaurs.
“Undoubtedly, the most surprising discovery concerning dinosaurs in the past 25 years has been the discovery of feathered dinosaurs in the province of Liaoning in China, and the realization that many theropod dinosaurs had at least a coverage of feathers and not reptilian scales,” said Dr. John Nudds, an eldest course of Palaeontology at the University of Manchester University.
“These were probably initially for the insulation of eggs, perhaps also for display, and were then modified for the flight. It turned out to be out of all reasonable doubts that birds have evolved from dinosaurs and are in fact dinosaurs.
Arctic dinosaurs
Imagine a jurassic landscape and you probably think of a jungle with some simmering volcanoes in the background. But scientists now believe that dinosaurs lived in much more varied climates, including the coldest extremes on the planet.
Recent analysis of Hundreds of fossils, including those of baby dinosaurs, have recovered from northern Alaska suggests that they reproduced in the region and it was probably their permanent home rather than a stop on a seasonal migratory pathway. The region would have been dropped in the dark for four months of the year and would have experienced temperatures well below the frost.
Weird, large and new species
T-Rex, Diplodocus, Stegosaurus: the former prevail over the kingdom of dinosaurs remained unchanged in popular imagination for decades. But no shortage of unique and charismatic species has been unearthed in the past 25 years, many paleontologists would like to see greater attention.
“One of the strangests is Deinocheirus,” said Professor Paul Barrett, paleontologist at the Natural History Museum in London. The species had been temporarily identified on the basis of the discovery of a gigantic pair of weapons in the 1960s, but it was not until 2014 when a pair of more complete skeletons was described that its unusual characteristics were fully to the point.
“It looks like the offspring of a night of passion between a radiator and a duck,” said Barrett. “He has a duck’s head, a huge sail on his back, side claws, he seems to have been assembled by a committee.”
“An absolutely amazing number of new species have been found,” said Hone, citing Yi qiA slippery dinosaur with feathers, like a personal favorite. “It is essentially a hybrid of a bird and a flying squirrel,” he said.
Over the past two decades, discoveries have also experienced larger species than ever discovered. Patagotitan (announced in 2014) has an estimated duration of 37 meters and an estimated weight of 69 tonnes, taking the title for the largest known land animal, and Dreadnoughts (Developed in 2005) at the height of its physique on the battleship.
“Some of these things grow 60 to 70 tonnes,” said Barrett. “We must understand the challenges they should have faced to move and eat.”
Dinosaurs who take the seas
While the former debates of dinosaurs began to rest, new ones took place. The discovery of a series of spinosaurus The fossils have opened a new battlefield on the question of whether these dinosaurs may have been adapted to life and hunting in water. It has already been assumed that dinosaurs live and only hunt on earth (the pleosaurs and the pliosaurs are marine reptiles, not dinosaurs).
“Is the big question that it was a prosecutor?” Or did he drive out like a huge heron and catch fish with his mouth? ” said Dr. Jeremy Lockwood, a GP who has become a paleontologist based on the island of Wight which Discovered a relevant specimen nicknamed “The Horned Crocodile Faced Heron”. “It is a furious controversy that allowed the world of paleontology.”
15 meters from snout to the tail, Spinosaurus is longer than any other meat eating dinosaur, has conical teeth like those observed in crocodiles, a long Newt -shaped tail and dense bones that could help it flow to swim under water.
However, computer simulations have raised questions about its hydrodynamic properties, a suggesting that it would have driven on the side when it was submerged, according to Lockwood. “I can see the two points of view, but I would not dream of setting up on one,” he said.
Lizards in a soft shell
Among the most important discoveries of the last decade is that of soft shell eggsWith fossilized embryos, as old as 200 million years. “All the eggs we had so far had like chicken eggs,” said Hone. The latest evidence suggests that many species of dinosaurs have laid soft shell eggs, something like those that are lizard or crocodiles today.
Even more intriguing, the analysis of the teeth of the embryos in some of the eggs, suggests that they have gesturing up to six months. This opens up a new view of the reproductive life of dinosaurs, which suggests that they may have buried eggs in nests or burrows.
“Do they take a nest for months at the same time?” Or dig a hole and searching and returning a year later to see if their babies have hatched? ” said hone. “All the options are really bizarre.”