Guardians of Grail Forum Index Guardians of Grail
The best PVKII Clan
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   GalleriesGalleries   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Cheap Christian Louboutin Shoes ydlw

 
Post new topic   Reply to topic    Guardians of Grail Forum Index -> General
View previous topic :: View next topic  
Author Message
cheapbag214s
Post Master
Post Master



Joined: 27 Jun 2013
Posts: 19871
Read: 0 topics

Warns: 0/5
Location: England

PostPosted: Mon 7:47, 09 Dec 2013    Post subject: Cheap Christian Louboutin Shoes ydlw

Birds evolved after decoupling normal limb size from body size
MONTREAL, Sept. 17 () -- A change in dinosaurs' limbs in relation to their bodies eventually led to the development of wings and their evolution [url=http://www.christianslouboutinvip.com/]Cheap Christian Louboutin Shoes[/url] into [url=http://www.ejglobal.com/blog.php?do=showone&type=blog&cid=6&itemid=1210768]http://www.ejglobal.com/blog.php?do=showone&type=blog&cid=6&itemid=1210768[/url] birds, Canadian researchers say.Birds originated from a group of small dinosaurs called maniraptorans about 150 million years ago, and recent findings show many maniraptorans were already very bird-like, with feathers, hollow bones, small body sizes and high metabolic rates, researchers at McGill University in Montreal said.But true birds began to evolve when both the forelimbs and hind limbs underwent a dramatic decoupling from body size, they said, allowing early birds to accomplish flight.Forelimbs lengthened and [url=http://house.focus.cn/msgview/8159/282309950.html]http://house.focus.cn/msgview/8159/282309950.html[/url] served as airfoils, while hind legs shrank, reducing [url=http://www.experienceproject.com/]http://www.experienceproject.com/[/url] drag in flight -- the reason modern birds tuck their legs as they fly -- and aiding perching and moving around on tree branches, they said.A combination of better [url=http://r.club.china.com/jsp/error/error.jsp?message=sessionTimeNot]http://r.club.china.com/jsp/error/error.jsp?message=sessionTimeNot[/url] wings [url=http://steven789789web.ihost.tw/viewthread.php?tid=25478&extra=page%3D1&frombbs=1]http://steven789789web.ihost.tw/viewthread.php?tid=25478&extra=page%3D1&frombbs=1[/url] and more compact legs would have been critical for the survival of birds in a time when another group of flying reptiles, the pterosaurs, dominated the skies and competed for food, the researchers said."Our findings suggest that birds underwent an abrupt change in their developmental mechanisms, such that their forelimbs and hind limbs became subject to [url=http://www.christianslouboutinvip.com/]Christian Louboutin Black Friday 2013[/url] different length controls," Hans Larsson, a McGill macroevolutionist, said.Deviations from the rules of how an animal's limbs normally scale with changes in body size usually indicate some major shift in function or behavior, the researchers said."The origin of birds and powered flight is a classic major evolutionary transition," said Alexander Dececchi, who participated in the study as a McGill graduate student and is now a postdoctoral [url=http://www.christianslouboutinvip.com/]Christian Louboutin Cyber Monday 2013[/url] researcher at the University of South Dakota. "Our findings suggest that the limb lengths of birds had to be dissociated from general body size before they could radiate so successfully."It may be that this fact is what allowed them to become more than just another lineage of maniraptorans and led them [url=http://www.christianslouboutinvip.com/]Christian Louboutin Discount[/url] to expand to [url=http://www.christianslouboutinvip.com/Louboutin-Men-Spiked-Sneakers-14/]Christian Louboutin Men Sneakers[/url] the wide range of limb shapes and sizes present in today's birds."


The post has been approved 0 times
Back to top
View user's profile
Display posts from previous:   
Post new topic   Reply to topic    Guardians of Grail Forum Index -> General All times are GMT + 1 Hour
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

fora.pl - załóż własne forum dyskusyjne za darmo
Powered by phpBB © 2001, 2005 phpBB Group
Regulamin