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Dinosaur extinction didn't cause the rise of present-day mammals, claim researchers
March 29, 2007A new, complete 'tree of life' tracing the history of all 4,500 mammals on Earth shows that they did not diversify as a result of the death of the dinosaurs, says new research published in Nature today.
The study was undertaken in the UK by scientists at Imperial College London and the Zoological Society of London (ZSL). It contradicts the previously accepted theory that the Mass Extinction Event (MEE) that wiped out the dinosaurs 65 million years ago prompted the rapid rise of the mammals we see on the earth today.
The multinational research team has been working for over a decade to compile the tree of life from existing fossil records and new molecular analyses. They show that many of the genetic 'ancestors' of the mammals we see around us today existed 85 million years ago, and survived the meteor impact that is thought to have killed the dinosaurs. However, throughout the Cretaceous epoch, when dinosaurs walked the earth, these mammal species were relatively few in number, and were prevented from diversifying and evolving in ecosystems dominated by dinosaurs.
The tree of life shows that after the MEE, certain mammals did experience a rapid period of diversification and evolution. However, most of these groups have since either died out completely, such as Andrewsarchus (an aggressive wolf-like cow), or declined in diversity, such as the group containing sloths and armadillos.
The researchers believe that our 'ancestors', and those of all other mammals on earth now, began to radiate around the time of a sudden increase in the temperature of the planet - ten million years after the death of the dinosaurs.
Professor Andy Purvis from Imperial College London's Division of Biology explains: "Our research has shown that for the first 10 or 15 million years after the dinosaurs were wiped out, present day mammals kept a very low profile, while these other types of mammals were running the show. It looks like a later bout of 'global warming' may have kick-started today's diversity - not the death of the dinosaurs.
"This discovery rewrites our understanding of how we came to evolve on this planet, and the study as a whole gives a much clearer picture than ever before as to our place in nature."
Dr Kate Jones from the Zoological Society of London adds: "Not only does this research show that the extinction of the dinosaurs did not cause the evolution of modern-day mammals, it also provides us with a wealth of other information. Vitally, scientists will be able to use the research to look into the future and identify species that will be at risk of extinction. The benefit to global conservation will be incalculable.\\\
Imperial College London
The tree of life shows that after the MEE, certain mammals did experience a rapid period of diversification and evolution. However, most of these groups have since either died out completely, such as Andrewsarchus (an aggressive wolf-like cow), or declined in diversity, such as the group containing sloths and armadillos.
The researchers believe that our 'ancestors', and those of all other mammals on earth now, began to radiate around the time of a sudden increase in the temperature of the planet - ten million years after the death of the dinosaurs.
Professor Andy Purvis from Imperial College London's Division of Biology explains: "Our research has shown that for the first 10 or 15 million years after the dinosaurs were wiped out, present day mammals kept a very low profile, while these other types of mammals were running the show. It looks like a later bout of 'global warming' may have kick-started today's diversity - not the death of the dinosaurs.
"This discovery rewrites our understanding of how we came to evolve on this planet, and the study as a whole gives a much clearer picture than ever before as to our place in nature."
Dr Kate Jones from the Zoological Society of London adds: "Not only does this research show that the extinction of the dinosaurs did not cause the evolution of modern-day mammals, it also provides us with a wealth of other information. Vitally, scientists will be able to use the research to look into the future and identify species that will be at risk of extinction. The benefit to global conservation will be incalculable.\\\
Imperial College London
Dinosaur Current Events and Dinosaur News RSSWarm-blooded dinosaurs worked up a sweat
Were dinosaurs "warm-blooded" like present-day mammals and birds, or "cold-blooded" like present day lizards? The implications of this simple-sounding question go beyond deciding whether or not you'd snuggle up to a dinosaur on a cold winter's evening.
The last European hadrosaurs lived in the Iberian Peninsula
Spanish researchers have studied the fossil record of hadrosaurs, the so-called 'duck-billed' dinosaurs, in the Iberian Peninsula for the purpose of determining that they were the last of their kind to inhabit the European continent before disappearing during the K/T extinction event that occurred 65.5 million years ago.
The humble beginnings of a king
Tyrannosaurus rex and related large carnivorous dinosaurs together form the family Tyrannosauridae. A long forgotten fossil skull in the collections of the Natural History Museum in London has now provided crucial clues to the early stages of the lengthy evolutionary history of these fearsome predators.
New dinosaur species from Montana
A husband and wife team of American paleontologists has discovered a new species of dinosaur that lived 112 million years ago during the early Cretaceous of central Montana.
New analyses of dinosaur growth may wipe out one-third of species
Paleontologists from the University of California, Berkeley, and the Museum of the Rockies have wiped out two species of dome-headed dinosaur, one of them named three years ago - with great fanfare - after Hogwarts, the school attended by Harry Potter.
Do 3 meals a day keep fungi away?
The fact that they eat a lot - and often - may explain why most people and other mammals are protected from the majority of fungal pathogens, according to research from Albert Einstein College of Medicine of Yeshiva University.
Crushed bones reveal literal dino stomping ground
Imagine the gruesome sound of bones snapping as a thirsty, 30-ton dinosaur tramples a heap of fresh carcasses on his way to a rapidly shrinking lake.
Chinese and American paleontologists discover a new Mesozoic mammal
An international team of paleontologists has discovered a new species of mammal that lived 123 million years ago in what is now the Liaoning Province in northeastern China.
Archaeopteryx was not very bird-like
New research published this week clips the wings of Archaeopteryx. First found in Germany in the 1860's and dating to 150 million years ago, Archaeopteryx has long been considered the iconic first bird.
Inside the first bird, surprising signs of a dinosaur
The raptor-like Archaeopteryx has long been viewed as the archetypal first bird, but new research reveals that it was actually a lot less "bird-like" than scientists had believed.
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Dozen Jumbo Dinosaurs up to 6 inches long by Toy C Set of 12 realistic toy dinosaur figures. Dinos are made from slightly flexible plastic, are hollow inside. Set includes: Ceratosaurus, Pachycephalosaurus, Stegosaurus, Parasaurolophus, Tyrannosaurus, Spinosaurus, Brachiosaurus, Velociraptor, Apatosaurus, Euoplocephalus, Triceratops, Styracosaurus. |
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ZipBin Dinosaur Playset by Neat Oh ZipBin is more than great-looking storage. It's a portable play world that unzips to reveal space to play, create and imagine. And it's easy to clean up... in a zip! The Dinosaur storage bin's dramatic exterior theme identifies the contents and will look great in your child's room. When the bin is unzipped, it becomes a dinosaur island play mat, complete with a colorful island, a volcano, and oozing tar pit and a mysterious cave. When play is done, the play mat becomes the storage bin in a zip, capturing the toys inside. Includes four dinosaurs: Tyrannosaurus Rex, Saurolophus, Triceratops, and Compsognathus, 4-5" long. ZipBin measures approximately 16" x 13" x 9". |
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My Big Dinosaur Book (My Big Board Books) by Roger Priddy (Author) |
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Scientific Explorer's My First Dinosaur Science Kit by Scientific Explorer With My First Dino Kit, You're a real paleontologist! Use excavation tools to dig up a dinosaur skeleton and then classify and display your findings. Build a glow in the dark model, or grow and shrink some giant dinos, all while you learn about the prehistoric past. Did some dinosaurs have feathers? Are crocodiles as ancient as the dinosaurs? You'll find out. Ages 4+ adult supervision required. |
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Mattel SCREATURE Interactive Dinosaur by Mattel Your own prehistoric pal! Dare pet his head? More bite than roar! Can you master Screature, or will you be his prey? Lifelike and realistic with ferocious sounds, Screature uses an infrared sensor to sense and attack his prey with your help. If you can control Screature, he will respond loyally to your petting, but if you pet him in the wrong place, Screature attacks! Set him in room guard mode and Screaturewill guard all your prized treasures! Screature is a mean little predator with a big appetite. Try me, open tray package. 3x 'AA' batteries included, with minor assembly required. |
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