Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Armour-plated fish and the evolution of dentists

08.01.2002


The discovery of small spikes lining the mouths of primitive fossil fish reveal surprising new details about how early animals fed. New research published today in a Royal Society paper sheds light on how teeth evolved.



Primitive fish did not have jaws or fins but were covered in rigid bony scales and resembled small armour-plated submarines. Dr Mark Purnell, a palaeontologist at the University of Leicester, has discovered that heterostracans, one of the most important groups of these early fish, had small spiky structures lining the inside edge of the mouth. These structures were made of hard dentine and were possibly the precursors of teeth as we know them today.

Only animals with backbones have true teeth, and the enamel and dentine of which they are made are the hardest materials in the body. ‘If you go looking for fossils of sharks, dinosaurs or any other vertebrate animal, you are more likely to find teeth than bones. Yet, surprisingly, mystery and uncertainty still surround the questions of when teeth first evolved and what they were used for,’ says Dr Purnell.


These new discoveries indicate that these early ‘teeth’ were not separated, individual structures but were modified from the armour plating that shielded the outside of the body. They had sharp points, cusps and ridges, but, unlike teeth, these points all faced forwards, and the fish could not have bitten or grabbed their food, or consumed anything but very small or soft items. This new evidence suggests that these early ‘teeth’ evolved not in a ferocious biting creature, but from the bony scales of a slime-slurping sucker.

Understanding how, when, and why animals first cut their teeth more than 400 million years ago is fundamental to understanding why the world around us is as it is. ‘Imagine a world without teeth – the history of life would certainly have taken a different course. Sharks would no longer be terrifying and dentists, more frightening to many people, would never have evolved,’ adds Dr Purnell.

Dr Mark Purnell | alphagalileo

More articles from Life Sciences:

nachricht 'Y' a protein unicorn might matter in glaucoma
23.10.2017 | Georgia Institute of Technology

nachricht Microfluidics probe 'cholesterol' of the oil industry
23.10.2017 | Rice University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Salmonella as a tumour medication

HZI researchers developed a bacterial strain that can be used in cancer therapy

Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Microfluidics probe 'cholesterol' of the oil industry

23.10.2017 | Life Sciences

Gamma rays will reach beyond the limits of light

23.10.2017 | Physics and Astronomy

The end of pneumonia? New vaccine offers hope

23.10.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>