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Postprzez coachoutlet22 » Śro Maj 02, 2018 11:34 am

"Jurassic Park" Had it Right: Some nike Dinosaurs Hunted by NightView a photo gallery showing the fossils the researchers studied. This material is available primarily for archivalpurposes. Telephone numbers or other contact information maybe out of date; please see current contact information at mediacontacts. Stephen Spielberg's movie Jurassic Park got one thing right. Velociraptors hunted by night while big oakley vault plant-eating dinosaurs browsed around the clock, according to a paper on the dsquared2 outlet eyes of fossil animals rolex montre published on-line this week in Science Express.

That overturns the orlando magic jersey conventional wisdom that dinosaurs were active by day while early mammals scurried around at night, said Ryosuke Motani, oakley outlet online a geologist at the University of California at Davis, and a co-author mont blanc of the paper. "It was a surprise, michael kors but it makes sense," Motani said. It's also providing insight into how ecology influences the evolution of animal shape and form over tens of millions of years, according to Motani and collaborator Lars Schmitz, a postdoctoral researcher at UC Davis.

"These authors' conclusion that these dinosaurs were active replica watches diurnally and nocturnally challenges a general dogma--that nocturnality in that time was mostly restricted to mammals," says H. Richard Lane, program director in the National Science Foundation (NSF)'s Division of Earth Sciences, which funded the michael kors research. Motani and Schmitz worked out the dinosaurs' daily habits by studying their eyes. nba jersey Dinosaurs, lizards and birds all have a bony ring michael kors outlet called the "scleral ring" in their eyes, although this is lacking in mammals and crocodiles.

Schmitz and Motani measured the inner and outer dimensions of this ring, plus longchamp outlet the size of the eye socket, in dansko shoes 33 adidas shoes fossils of dinosaurs, ancestral birds and pterosaurs--and in 164 living species. Day-active, or diurnal animals have a small opening in the middle of the ring while the opening is much larger in nocturnal animals. Cathemeral animals--active in both day mont blanc pens and night--tend to be in between.

But the size of these features is also affected by ancestry. For example, two closely related animals might have similar eye shape even if one is active by day and the other by night: the shape of the eye is constrained asics outlet by ancestry, and that could bias the results. Schmitz and Motani developed a computer program to separate the "ecological signal" from this "phylogenetic signal." The detroit pistons jerseys results of that analysis are in air jordans a separate paper published simultaneously in the journal eyeglass frames Evolution. By looking at a 164 living species, they could confirm that the eye measurements wereaccurate in predicting whether animals were active by day, by night or around the clock.

Then nike air max they applied the technique to fossils, including plant-eating nike shoes outlet and carnivorous dinosaurs, flying reptiles called pterosaurs and ancestral birds.The new york knicks jerseys big plant-eating dinosaurs were active day and night, probably because they had to eat most of the time, except toms shoes for the hottest hours of the day when they avoided overheating. Modern megaherbivores like elephants show the same activity pattern, Motani said.Velociraptors and other small carnivores were night hunters.

Schmitz and Motani were not able to study big carnivores such as Tyrannosaurus rex, because there are no thomas sabo charms fossils with sufficiently well-preserved eyes. Flying creatures, including early birds and pterosaurs, were mostly day-active, although some of the polo ralph lauren outlet pterosaurs--including a filter-feeding animal that probably lived like a tods shoes outlet duck, and a fish-eating pterosaur--were apparently night-active. "

This strongly suggests cheap oakley sunglasses that ecology drives activity," Schmitz said. By separating out the effects of ancestry, researchers now have a tool to understand how animals lived in their environment and how changes in the environment influenced their evolution over millions of pandora outlet years, Motani said. The work ferragamo was also funded a postdoctoral fellowship from the German government michael kors outlet (DFG).
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