- Dinosaurs 'survived in a remote 'lost world' for half a million years before extinction'
- Dinosaurs declined before mass extinction
- Beaked, bird-like dinosaur tells story of finger evolution
- Sands of Gobi Desert yield new species of nut-cracking dinosaur
- First dino 'blood' extracted from ancient bone
- Discovery raises new doubts about dinosaur-bird links
- Dolphins maintain round-the-clock visual vigilance
- Scientists discover ultrasonic communication among frogs
- Darwin in a test tube: Scientists make molecules that evolve, compete, mimick behavior of Darwin's finches
As for the short stories, they all show how little we actually know about animals and their skills and intellect.
Dinosaurs 'survived in a remote 'lost world' for half a million years before extinction'
By Richard Alleyne
01 May 2009
Until now, palaeontologists widely believed the creatures were wiped out 65 million years ago when an asteroid collided with Earth. But now experts say a "pocket" of dinosaurs survived and roamed a remote area of what is now New Mexico and Colorado.
Carbon dating of newly-discovered bones in the San Juan Basin proves that these lived for another half-a-million years. The discovery, published this week in the journal Palaeontologia Electronica, has been hailed as one of the most important breakthroughs in palaeontology this century.
The bones were discovered buried at Ojo Alamo, a soft sandstone valley deep in the remote San Juan Basin. A team of experts unearthed the bones, which included 34 from a single hadrosaur, and used carbon dating techniques to age them.
According to the results, they were 500,000 years younger than any other dinosaur bones previously found. source
My comment: So, evidence number 1. It seems likely to me that some dinosaurs really survived. Is there a reason why they wouldn't? They were everywhere on the planet (as new evidences suggest, some lived even in Northern regions), we cannot expect that they all were affected to the same extent by the Event. And if some of them survived the crazy climate, they could have found what to eat and even multiplied for a while. But in view of the hostility of the environment, they could never become the masters of the Earth again. Note how many myths tell us that dragons lived along in caves, often the last of their kind (no wonder about this-almost every hero killed a bunch of them).
Dinosaurs declined before mass extinctionApril 30th, 2009
Dinosaurs were dying out much earlier than the mass extinction event 65 million years ago, Natural History Museum scientists report in the Proceedings of the Royal Society journal today.
The diversity of dinosaur species was already on the decline millions of years before this event. This changes the current theory about how and when dinosaurs became extinct.
Until now, the common theory was that all dinosaurs, except the ancestors of birds, were wiped out at one time, perhaps by a huge meteorite, at the end of the Cretaceous period. Many dinosaur species such as Triceratops were wiped out abruptly around this time. However, this does not tell the full story.
Barrett and his team found that most species, such as those in the theropod group, like Baryonyx and T.rex, had already declined millions of years earlier.
Barrett and his team's results uncovered a relationship between the amount of fossil-containing rock available and the pattern of species diversity. In general, the more rock available, the higher the diversity uncovered.
The diversity decline at the end of the Cretaceous was at a time in Earth's history when plenty of rock and fossils were preserved. So the high amount of available rock from this time should have shown a high diversity of dinosaurs if there was one. But it didn't. source
My comment:Evidence 2. Why did the dinosaurs decline? First, I have to underline this is an indirect evidence, but still, they were the masters of the Earth, they should have thrived. I don't have a response. I think they might have come to a point where further development was unsustainable ( does this ring a bell? ) or maybe they have found the optimal variety and were just enjoying their peaceful life. Or (more likely) there's something big we simply miss out.
Beaked, bird-like dinosaur tells story of finger evolutionJune 17th, 2009 James Clark, and Xu Xing, have discovered a unique beaked, plant-eating dinosaur in China. This finding demonstrates that theropod, or bird-footed, dinosaurs were more ecologically diverse in the Jurassic period than previously thought and offers important new evidence about how the three-fingered hand of birds evolved from the hand of dinosaurs.
Limusaurus inextricabilis was found in 159 million-year-old deposits located in the Junggar Basin of Xinjiang, northwestern China. A close examination of the fossil shows that its upper and lower jaws were toothless, demonstrating that the dinosaur possessed a fully developed beak. Its lack of teeth, short arms without sharp claws and possession of gizzard stones suggest that it was a plant-eater, though it is related to carnivorous dinosaurs.
The newly discovered dinosaur's hand is unusual and provides surprising new insights into a long-standing controversy over which fingers are present in living birds, which are theropod dinosaur descendants. The hands of theropod dinosaurs suggest that the outer two fingers were lost during the course of evolution and the inner three remained. Conversely, embryos of living birds suggest that birds have lost one finger from the outside and one from the inside of the hand. Unlike all other theropods, the hand of Limusaurus strongly reduced the first finger and increased the size of the second. Drs. Clark and Xu and their co-authors argue that Limusaurus' hand represents a transitional condition in which the inner finger was lost and the other fingers took on the shape of the fingers next to them. The three fingers of most advanced theropods are the second, third and fourth fingers--the same ones indicated by bird embryos--contrary to the traditional interpretation that they were the first, second and third.
Limusaurus is the first ceratosaur known from East Asia and one of the most primitive members of the group. Ceratosaurs are a diverse group of theropods that often bear crests or horns on their heads, and many have unusual, knobby fingers lacking sharp claws. source
My comment: First-I suggest you read the article at the source, because I edited it quite much. But note-this dino had 5 fingers! Which I find stunningly odd. Why five? And something else, how come birds are descendants of dinosaurs when they all went happily (or not so much) extinct 65 million years ago? I don't want to sound crazy and offer some reptile conspiracy. I'm just curious-after all if the birds could descend from dinosaurs then something survived and lived on. Why? And how? And is there more?
Sands of Gobi Desert yield new species of nut-cracking dinosaurJune 17th, 2009
Plants or meat: That's about all that fossils ever tell paleontologists about a dinosaur's diet. But the skull characteristics of a new species of parrot-beaked dinosaur and its associated gizzard stones indicate that the animal fed on nuts and/or seeds. These characteristics present the first solid evidence of nut-eating in any dinosaur.
"The parallels in the skull to that in parrots, the descendants of dinosaurs most famous for their nut-cracking habits, is remarkable," said Paul Sereno, a paleontologist at the University of Chicago and National Geographic Explorer-in-Residence.
The paleontologists discovered the new dinosaur, which they've named Psittacosaurus gobiensis, in the Gobi Desert of Inner Mongolia in 2001. The dinosaur is approximately 110 million years old, dating to the mid-Cretaceous Period.
The quantity and size of gizzard stones in birds correlates with dietary preference. Larger, more numerous gizzard stones point to a diet of harder food, such as nuts and seeds. "The psittacosaur at hand has a huge pile of stomach stones, more than 50, to grind away at whatever it eats, and this is totally out of proportion to its three-foot body length," Sereno explained.
Technically speaking, the dinosaur is also important because it displays a whole new way of chewing, which Sereno and co-authors have dubbed "inclined-angle" chewing.
The unusual chewing style has solved a major mystery regarding the wear patterns on psittacosaur teeth. Psittacosaurs sported rigid skulls, but their teeth show the same sliding wear patterns as plant-eating dinosaurs with flexible skulls. source
My comment: This isn't really an evidence, but it's interesting, because it shows the variety of dinosaurs. Obviously, there's more to them than just a huge lizard trying to rip off the head of sexy blond.
First dino 'blood' extracted from ancient bone
- 19:00 30 April 2009 by Jeff Hecht
A dinosaur bone buried for 80 million years has yielded a mix of proteins and microstructures resembling cells. The finding is important because it should resolve doubts about a previous report that also claimed to have extracted dino tissue from fossils.
Proteins such as collagen are far more durable than DNA, but they had not been expected to last the 65 million years since the dinosaurs died out. So palaeontologist Mary Schweitzer of North Carolina State University attracted wide attention when she reported finding first soft tissue and later collagen from a Tyrannosaurus rex leg bone that was intact until it was broken during excavation.
Schweitzer took a look at the pristine leg bone of a plant-eating hadrosaur that had been encased in sandstone for 80 million years.
Now they report recovering not just collagen – which conveys little evolutionary information because it is the same in almost all animals – but also haemoglobin, elastin and laminin, as well as cell-like structures resembling blood and bone cells. The proteins should reveal more about dinosaur evolution because they vary much more between species. sourceMy comment: Nice. Maybe then one day, we'd able to know more about their physiology, which could tell us more about the way their brain worked. And ultimately, how intelligent they were!
Discovery raises new doubts about dinosaur-bird linksJune 9th, 2009
It's been known for decades that the femur, or thigh bone in birds is largely fixed and makes birds into "knee runners," unlike virtually all other land animals, the OSU experts say. What was just discovered, however, is that it's this fixed position of bird bones and musculature that keeps their air-sac lung from collapsing when the bird inhales.
However, every other animal that has walked on land, the scientists said, has a moveable thigh bone that is involved in their motion - including humans, elephants, dogs, lizards and - in the ancient past - dinosaurs.The implication, the researchers said, is that birds almost certainly did not descend from theropod dinosaurs, such as tyrannosaurus or allosaurus. The findings add to a growing body of evidence in the past two decades that challenge some of the most widely-held beliefs about animal evolution.
The newest findings, the researchers said, are more consistent with birds having evolved separately from dinosaurs and developing their own unique characteristics, including feathers, wings and a unique lung and locomotion system.
There are some similarities between birds and dinosaurs, and it is possible, they said, that birds and dinosaurs may have shared a common ancestor, such as the small, reptilian "thecodonts," which may then have evolved on separate evolutionary paths into birds, crocodiles and dinosaurs. The lung structure and physiology of crocodiles, in fact, is much more similar to dinosaurs than it is to birds."source
My comment: Ok, on this I'm clueless. Though it goes well with the previous article. What do we know and how much we don't know?
Dolphins maintain round-the-clock visual vigilanceMay 1st, 2009
Dolphins have a clever trick for overcoming sleep deprivation. Sam Ridgway from the US Navy Marine Mammal Program explains that they are able to send half of their brains to sleep while the other half remains conscious. What is more, the mammals seem to be able to remain continually vigilant for sounds for days on end.
Kamolnick trained one of the dolphins, SAY, to recognise two shapes with her right eye before training her to recognise the same shapes with the left eye, reasoning that if half of her brain was asleep during testing, the dolphin would only see the shapes through the eye connected to the conscious half of the brain. But the team were in for a surprise when they began training SAY's left eye. She already recognised the shapes, even though her left eye had not seen them previously. Ridgway explains that the information must be transferred between the two brain hemispheres and suspects that the dolphin's inter-hemispheric commissures, which connects the two halves, may transfer the visual information.
Amazingly, even after 5 days of listening out for 1.5 s beeps amongst the 0.5 s beep background, the dolphins were still responding as accurately as they had done at the beginning of the experiment. And when the team checked the dolphins' blood for physical signs of sleep deprivation, they couldn't find any. After 5 days of unbroken vigilance the dolphins were in much better shape than the scientists. source
Scientists discover ultrasonic communication among frogsMay 11th, 2009
(PhysOrg.com) -- UCLA scientists report for the first time on the only known frog species that can communicate using purely ultrasonic calls, whose frequencies are too high to be heard by humans. Known as Huia cavitympanum, the frog lives only on the Southeast Asian island of Borneo.
The frogs can hear sounds up to 38 kilohertz, the highest frequency any amphibian species has been known to hear, the scientists report. Humans can hear up to about 20 kHz and typically talk at 2 or 3 kHz.
While most of the more than 5,000 frog species worldwide have eardrums that are flat on the side of the head, Huia cavitympanum has eardrums recessed in the side of the skull, similar to mammals.
Huia cavitympanum produces some audible calls and others that are entirely ultrasonic.
Narins and Arch have an idea about why the frogs, which live along a noisy stream, use both ultrasonic communication and calls that are audible to humans.
"Our hypothesis is that these frogs have shifted to use higher frequencies in their communication to avoid the interference of sound produced by rushing water in the lower-frequency range," Arch said. "However, high-frequency sounds do not transmit as far. By producing some lower-frequency calls, they can transmit calls over a greater distance, so they can communicate with frogs that are farther away. But by also producing some calls that are high-frequency — all ultrasonic — they may be able to communicate better over that background noise.
The frogs in China produce very loud calls that are, at the same time, both audible and ultrasonic. In Borneo, however, Huia cavitympanum produces some sounds that are purely ultrasonic. source
Darwin in a test tube: Scientists make molecules that evolve, compete, mimick behavior of Darwin's finchesApril 29th, 2009
As described in an article published this week in an advance, online edition of the journal Proceedings of the National Academy of Sciences (PNAS), the work demonstrates some of the classic principles of evolution. For instance, research shows that when different species directly compete for the same finite resource, only the fittest will survive. The work also demonstrates how, when given a variety of resources, the different species will evolve to become increasingly specialized, each filling different niches within their common ecosystem. source