Featured Research

from universities, journals, and other organizations

Dinosaurs In Bullet-proof Vests

Date:
November 17, 2004
Source:
University Of Bonn
Summary:
Their armour was perfect; even their eyelids consisted of plates of bone. What are known as ankylosauruses are among the best armoured animals known to us. These herbivores were up to ten metres long, with a tail ending in a huge bony club – 'probably used as a weapon', says Torsten Scheyer, 'even though they definitely could not simply swing it back and forth; the whole construction was simply too stiff for that.'

Torsten Scheyer with a model, which demonstrates the fiber direction in the bone plates.
Credit: Image courtesy of University Of Bonn

Their armour was perfect; even their eyelids consisted of plates of bone. What are known as ankylosauruses are among the best armoured animals known to us. These herbivores were up to ten metres long, with a tail ending in a huge bony club – 'probably used as a weapon', says Torsten Scheyer, 'even though they definitely could not simply swing it back and forth; the whole construction was simply too stiff for that.'

Torsten Scheyer has examined the dinosaurs' armour as part of his diploma thesis. The results are astonishing: 'The armour plating is not nearly as similar to those of the crocodile as was previously assumed,' he adds. 'Their microstructure is substantially more complex, at least in some types of ankylosaurus.'

A complete set of dinosaur chain mail was composed of hundreds of thousands of bony armour plates known as osteoderms. Most of these were smaller than a European one-cent coin, but some also had a diameter of several dozen centimetres and ended in long points. 'Unlike tortoise shells, the individual plates lay next to each other. They were not fused together,' the PhD student Torsten Scheyer explains. This kind of armour was flexible and could thus not break so easily under pressure. Although modern crocodiles have a similar kind of armour, the individual plates have a much simpler structure.

By using a polarisation microscope Torsten Scheyer discovered that collagen fibres were interwoven in the bone calcium of the dinosaur's armour plating, forming mats which were interspersed with each other three-dimensionally. Within each mat the fibres were aligned parallel to one another, with the fibres at right angles to the layer above and below them. 'The armour was thereby endowed with great strength in all directions,' Torsten Scheyer stresses. Today's composite materials are based on the same principle, which are used to make the rotor blades for wind farms or bullet-proof vests – except that in these cases the collagen mats are replaced by glass or carbon fibres.

Collagen is a protein found in connective tissue, sinews or cartilage. The ankylosauruses' armour plating was formed in the layer of connective tissue, thereby surrounding the existing collagen network. In the process of fossilisation this network decays, being replaced by minerals. 'In the fossils the pattern of the fibres can often still be traced, even after hundreds of millions of years,' Torsten Scheyer adds.

Some armour plating is even more stable

Palaeontologists divide the ankylosaurus into three subdivisions. The bullet-proof vest structure can only be proved in one of these; a second type has a relatively simple kind of armour plating. In the third group the armour paradoxically consists of what is known as haversian bone, a form which was first described in human beings in the 17th century by the British anatomist Dr. Clopton Havers. In the course of people's lives their bones are restructured. The trabeculae in the inside of the bones dissolve and are replaced by numerous small tubes of bone known as osteons. This reduces the stability of the bones and is one cause of the well-known phenomenon of brittle bones among the elderly. Torsten Scheyer explains, 'Ankylosauruses have these osteons, too, but in contrast to humans these are also strengthened with fibres.'

Possibly these collagen fibres are the reason why this third type of armour plating is even more stable than the 'normal' ankylosaurus armour. 'In this third group the plates of bone are far thinner than in all the other ankylosauruses – this cuts down weight and nutrients.' He adds, however, that despite this the armour was probably difficult to crack, not only because of their reinforcement with fibres: 'These thin plates of bone were shaped in such a sophisticated way that they could cope with pressure much better and did not break so easily.'


Story Source:

The above story is based on materials provided by University Of Bonn. Note: Materials may be edited for content and length.


Cite This Page:

University Of Bonn. "Dinosaurs In Bullet-proof Vests." ScienceDaily. ScienceDaily, 17 November 2004. <www.sciencedaily.com/releases/2004/11/041116214722.htm>.
University Of Bonn. (2004, November 17). Dinosaurs In Bullet-proof Vests. ScienceDaily. Retrieved April 17, 2014 from www.sciencedaily.com/releases/2004/11/041116214722.htm
University Of Bonn. "Dinosaurs In Bullet-proof Vests." ScienceDaily. www.sciencedaily.com/releases/2004/11/041116214722.htm (accessed April 17, 2014).

Share This



More Fossils & Ruins News

Thursday, April 17, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Couple Finds Love Letters From WWI In Attic

Couple Finds Love Letters From WWI In Attic

Newsy (Apr. 17, 2014) A couple found love letters from World War I in their attic. They were able to deliver them to relatives of the writer of those letters. Video provided by Newsy
Powered by NewsLook.com
Erotic Art Offers Glimpse of China's 'lost' Sexual Philosophy

Erotic Art Offers Glimpse of China's 'lost' Sexual Philosophy

AFP (Apr. 16, 2014) Explicit Chinese art works dating back centuries go on display in Hong Kong, revealing China's ancient relationship with sex. Video provided by AFP
Powered by NewsLook.com
French Historians Fight to Save Iconic La Samaritaine Buildings

French Historians Fight to Save Iconic La Samaritaine Buildings

AFP (Apr. 15, 2014) Parisians and local historians are fighting to save one of the French capital's iconic buildings, the La Samaritaine department store. Duration: 01:42 Video provided by AFP
Powered by NewsLook.com
Bee Fossils Provide Insight Into Ice Age Environment

Bee Fossils Provide Insight Into Ice Age Environment

Newsy (Apr. 12, 2014) Archeologists have found many fossils in the La Brea Tar Pits, including those of saber-tooth tigers and mammoths. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins