Why Do We Have An Internal Skeleton?

Описание: If you think about it, skeletons aren't awesome. Instead of the super strong shells or exoskeletons so many other animals have, we have these internal skeletons. That leaves or fragile bodies highly vulnerable to all kinds of serious injury. But as Trace explains, our internal skeletons are actually an evolutionary advantage.

Read More:

What if people had exoskeletons?
http://science.howstuffworks.com/life...
"Human beings are like reptiles, amphibians, birds, and fish in the fact that we all have internal skeletons. Muscles connect to the skeleton to provide motion, and we have soft skin on the outside."

Why Exoskeletons Exist
http://scienceline.ucsb.edu/getkey.ph...
We've learned that all arthropods have a tough outer covering called an exoskeleton. However, we have also learned that some arthropods, such as "honey-pot" ants and ticks actually expand as they collect honey or blood in their body. Is the exoskeleton able to expand? Do these organisms have a different type of exoskeleton that other arthropods?

Where did bone come from?
http://www.ncbi.nlm.nih.gov/pmc/artic...
"Bone is specific to vertebrates, and originated as mineralization around the basal membrane of the throat or skin, giving rise to tooth-like structures and protective shields in animals with a soft cartilage-like endoskeleton."

Exoskeleton Evolution
http://www.calacademy.org/sciencetoda...
"Less than three inches long, it has nonetheless made quite an impression. Diania cactiformis, more affectionately known as the "walking cactus," has given scientists new clues to the evolution of arthropods."

Skeletal System
http://hes.ucfsd.org/gclaypo/skelweb/...
"Your Skeletal system is all of the bones in the body and the tissues such as tendons, ligaments and cartilage that connect them.
Your teeth are also considered part of your skeletal system but they are not counted as bones. Your teeth are made of enamel and dentin. Enamel is the strongest substance in your body."

The problem with giant exoskeletons
http://www.forestazuaron.com/2012/bio...
"Last week we looked into a problem most fantasy worlds have, and this week we're looking at a related, but more specific, problem endemic to science fiction. The Ender series. Starship Troopers. Them! (and dozens of other horror classics)."

Oldest human skeleton offers new clues to evolution
http://www.cnn.com/2009/TECH/science/...
"The oldest-known hominid skeleton was a 4-foot-tall female who walked upright more than 4 million years ago and offers new clues to how humans may have evolved, scientists say."

Invertebrate vs Vertebrate
http://www.diffen.com/difference/Inve...
"Animals can be classified into two main groups: Vertebrates and invertebrates. The main difference between vertebrates and invertebrates is that invertebrates do not have a backbone or a spinal column."

Watch More:
All About Penis Bones:
   • Penises Have Bones?!  
TestTube Wild Card:
http://testtube.com/dnews/dnews-114-w...
Why Can't We Regrow Teeth?
   • Why Can't We Regrow Teeth?  

____________________

DNews is dedicated to satisfying your curiosity and to bringing you mind-bending stories & perspectives you won't find anywhere else! New videos twice daily.

Watch More DNews on TestTube http://testtube.com/dnews

Subscribe now! http://www.youtube.com/subscription_c...

DNews on Twitter   / dnews  

Anthony Carboni on Twitter   / acarboni  

Laci Green on Twitter   / gogreen18  

Trace Dominguez on Twitter   / trace501  

DNews on Facebook   / dnews  

DNews on Google+ http://gplus.to/dnews

Discovery News http://discoverynews.com