Dwarf Dinosaurs Lived on 'Neverland'-Like Island

By Jennifer Viegas

The largest group of animals ever to walk the earth included dwarf varieties.
Vlad Codrea

THE GIST:

• Dwarf dinosaurs existed on a Late Cretaceous island, a new analysis of bones confirms.
• Dwarf dinosaurs appear to have emerged from a process called progenesis, which shortens the developmental period.
• The dwarf dinosaurs lived fast, reaching sexual maturity at earlier ages than their mainland counterparts, and they likely died young.

---

When Hungarian baron Franz Nopcsa claimed that his sister in 1895 found bones belonging to dwarf dinosaurs on his family's Transylvanian estate, many thought his claims were on par with Count Dracula fiction.

A new study not only confirms the existence of dwarf dinosaurs, but also explains how dinosaurs shrank during the Late Cretaceous at a Neverland-like place -- Hateg Island, Romania -- where dinos never really grew up.

According to the study, which has been accepted for publication in the journal Palaeogeography, Palaeoclimatology, Palaeoecology, the unusual phenomenon appears to have only affected some of the island's dinosaur residents.

WATCH VIDEO: From a tiny, tough guy T. rex to a mummified duck-billed dino, take a look at these stories and more in these dinosaur videos.

Related Links:

---

• New Tyrannosaur Had More Teeth Than T. Rex
• Stolen Dino Fossil Found in Montana
• HowStuffWorks.com: Late Cretaceous Period
• World's 'First Bird' Was More Dinosaur than Bird

---

"The other animals living with the dinosaurs -- fish, frogs, albanerpetonids (salamander-like amphibians), turtles, crocodilians, pterosaurs, birds, lizards, snakes, and mammals -- were generally much smaller anyway, but so far haven't shown obvious size differences from mainland relatives," lead author Michael J. Benton told Discovery News.

Benton, who directs the Palaeobiology and Biodiversity Research Group at the University of Bristol, and his colleagues conducted one of the most extensive studies yet on the Hateg Island dinosaur remains. They analyzed the dinosaurs' limb proportions and bone growth patterns, comparing them with those of mainland dinos.

The analysis determined that at least four of the Hateg dinosaurs were dwarves.

The diminutive dinosaurs included the titanosaurian sauropod Magyarosaurus, which had a body length of about 16 to 19 feet. That's impressive by human standards, but is miniature compared to a sauropod such as Argentinosaurus, which grew to be at least 82 feet long.

Another small dinosaur was the hadrosaurid Telmatosaurus. Its 13-foot-long body contrasted with the average size of other hadrosaurids, which were 23 to 33 feet long, according to Benton.

Two species of Zalmoxes dinosaurs also appear to have been dwarves, with one -- Zalmoxes robustus -- measuring about 10 feet in length.

"So these forms are all typically half the length of their close relatives on larger land masses, and this equates to a body mass of perhaps one-eighth that of the relatives," said Benton. "Body mass is what matters most in biological terms, such as physiology and food intake."

Magnified sections of the dinosaurs' bones revealed that the animals were adults and not juveniles. The scientists believe the dinosaurs likely shrank due to a process called progenesis, which shortens the developmental period. Sexual maturity happened early, and these dinosaurs may have also died two to five years younger than their "normal"-sized counterparts.

"This in-depth study by Benton and colleagues is both fascinating and provocative," paleontologist Scott Sampson, a research curator at the Utah Museum of Natural History, told Discovery News, "demonstrating that the largest group of animals ever to walk the earth included dwarfed varieties."

Sampson added that the study also supports "the more general 'island rule'-- the idea that, when marooned on islands, evolution tends to make large animals smaller, and small animals larger."

Scientists continue to debate why this happens on islands. Reduced supplies of food, smaller ranges, and few larger predators have all been theorized.

"I think most biologists accept that there is something going on, and that the island rule has validity," Benton said.

Original here

Directed Panspermia: Moral Obligation or Bio-Pollution?

By Ian O'Neill

The Huygens probe as it descended through Titan's atmosphere in 2004. Could a similar delivery method seed life on other worlds? (NASA)

The speculative mechanism of panspermia could explain how life formed on Earth and how it might exist elsewhere in our solar system and beyond. Hitching rides on chunks of rock blasted into space by meteorite impacts or gliding through space on a comet, it turns out that "life as we know it" has an astonishing knack of surviving in the most extreme environments.

But what if mankind could purposefully launch space probes packed with little biological "starter kits" toward star systems that appear to have the potential to nurture life? We have lots of life down here, isn't it our duty to spread our seed amongst the stars?

WATCH: Extremophiles, micro-organisms that can live in volcanos, space and the deep oceans, are still a mystery, but one scientist has found a way to use them to study other elements.

Yes, says Michael Mautner, Research Professor of Chemistry at Virginia Commonwealth University, in a paper submitted to an upcoming issue of the Journal of Cosmology. Before the rich biosphere of Earth is dead, Mautner believes that we need to ship Earth Brand™ biology to suitable adopted homes so our evolutionary line has a chance to gain a foothold elsewhere in the universe.

"We have a moral obligation to plan for the propagation of life, and even the transfer of human life to other solar systems which can be transformed via microbial activity, thereby preparing these worlds to develop and sustain complex life," Mautner said. "Securing that future for life can give our human existence a cosmic purpose."

These are certainly lofty plans, but he proposes that we send a variety of basic organisms to "potentially fertile" worlds throughout the universe (to worlds from a few to over 500 light years away). Using early-Earth as an example, organisms like cyanobacteria could be sent to alien worlds to go into reproductive overdrive, feasting on toxic gases and releasing byproducts such as oxygen.

These little biological starter kits would support a brand new biosphere, helping more complex life forms to develop and evolve.

(Is anyone else thinking this was borrowed from the plot of Star Trek III: The Search for Spock?)

In his paper, Mautner goes into some detail about what this galactic seeding mission would look like. As current launch costs are astonishingly high (using current technology, it costs $10,000 to get a one kilogram payload off the Earth's surface and into space), the space seeding pods would need to be small. But using tiny "pods" weighing only 0.1 grams, as many as 100,000 microorganisms could be accommodated to give a reasonable chance of success.

Perhaps surprisingly, he indicates that we'd need "hundreds of tons" of biological material. But in this case, the launch costs would be a modest $1 billion; a bargain considering we'd be ensuring the continuation of Earth Brand™ life on various new worlds.

All these plans are completely speculative however, and to put a cost on such a mission is fanciful at best. Although Prof. Mautner does a great job of identifying how we could go about flinging our seed to the furthermost reaches of the galaxy, I'd question the fundamental point of "directed panspermia" at all. Is it really our "moral responsibility"?

I understand that we -- as life forms -- see the whole life thing as sacred, but what if one of these biological pods fertilizes a world where another life form is struggling to survive? Who are we to say that our Earth Brand™ life is superior to another brand of alien microbe?

If our life takes hold of a planet where another life had the opportunity to evolve into an interstellar civilization in a couple of billions of years time, wouldn't we be in violation of some kind of cosmic anti-monopoly regulation (or at least in violation of the Prime Directive)?

And there's another thing to ponder: What if "life" is the universal equivalent of some kind of infection. Is life rare because the universe has a very strong immune system? Firing our genetic code far and wide could be considered to be biological pollution.

I'm all for spreading the human influence around the galaxy, but I think this can only be considered if we physically go to these alien worlds, to evaluate these places in person before we start setting up home. Blindly sending life from Earth to habitable worlds and planet-forming accretion disks seems a little reckless, especially as we have no clue about the consequences if we started impregnating unsuspecting planets.

I know these points are just as speculative as Mautner's paper, but it does make you wonder whether sending it into space is really a "moral responsibility" when we have little clue about who or what we are in the grand (cosmic) scale of things.

Just because we've got it doesn't mean the rest of the universe wants it.

Original here

Martian Dune Mystery Solved by Bouncing Sand Grains Read More http://www.wired.com/wiredscience/2010/02/martian-dune-mystery-solved-by-bouncing-sand-

By Lisa Grossman, Science News

Once Martian sand grains hop, they don’t stop.

That’s the conclusion of a new study that finds sand can move on Mars without much windy encouragement.

Mars’ sandy surface has clearly been shaped by wind. Its characteristic dunes and ripples are the kind formed by sand particles taking short wind-borne hops, a process called saltation.

But atmospheric simulations and landers’ direct measurements of wind speed have found that the Martian wind hardly ever blows hard enough to kick sand grains off the ground in the first place.

The new paper, to appear in an upcoming Physical Review Letters, suggests a solution to this paradox: a kind of billiard-ball effect in which one sand particle knocks the next one into motion. “It’s much easier to keep this process going than it is to start it in the first place,” says study author Jasper Kok, an atmospheric physicist at the National Center for Atmospheric Research in Boulder, Colo., who did most of this research while at the University of Michigan in Ann Arbor. “It’s like when you ride a bike: It costs a lot of exertion to get it going, but once you’re going it’s easier to keep going.”

Kok modified a numerical model, previously applied to geological processes on Earth, to include Martian gravity and atmospheric conditions. Unlike in other models, Kok simulated a process called splashing, in which a flying sand particle knocks at least one new grain into the air as it smacks into the ground.

“That’s hard to study in a wind tunnel,” notes planetary scientist Robert Sullivan of Cornell University. The study “goes numerically where we have a hard time going with wind tunnel experiments,” he says.

The way sand grains knock each other around turns out to make all the difference, Kok says. Because Martian gravity and air density are so much lower than Earth’s, a small kick from the wind sends sand particles on Mars flying much higher, up to a meter off the ground.

“It’s like playing golf on the moon,” Kok says. Particles get caught in stronger winds as they rise, causing them to pick up speed and ultimately slam into the ground, where they kick up more particles and start the cycle over. “This splashing process is really efficient,” Kok says. “It can keep saltation, or sand blowing, going on Mars at relatively low wind speeds.” These jumping sand grains can create ripples over time even without high sustained winds, he says.

The finding could help solve other puzzles in the Martian landscape. Earlier models predicted that crescent-shaped sand dunes called barchan dunes should grow to at least 500 meters long — but many are only 100 meters. And the Mars rover Opportunity has found sand ripples made up of particles only 100 micrometers in diameter, so small that scientists had expected them to stay aloft once kicked up. The new model could explain both riddles by showing that splashing can keep particles moving at low wind speeds. Slow-moving sand grains don’t travel far and therefore make short dunes, but even tiny particles can get pushed into ripples, Kok says.

“This study is very welcome, very informative,” Sullivan says. “The results go a long way toward explaining several mysteries.”

Images: Martian dunes imaged by HiRISE 1) Barchan dunes. 2) Barchan dunes. 3) Megaripples. Credit: NASA/JPL/University of Arizona.

Original here