Study pits man v. machine in piecing together 425-million-year-old jigsaw

November 16, 2009

A new study pitting academic expertise against a computer in recreating a 425 million-year old jigsaw puzzle has discovered that there is no substitute for wisdom born out of experience.

The research tested the reliability of expert identification versus computer analysis in reconstructing fossils. The investigation, based on fossil teeth from extinct vertebrates, found that the most specialized experts provided the most reliable identifications.

University of Leicester researcher Dr Mark Purnell said: "Being a palaeontologist can be fun, but sometimes it isn't easy. Take vertebrates, the group to which we belong. When a vertebrate animal dies, whether it's a fish, a sabre-tooth cat or a dinosaur, the flesh rots away and the bones of the skeleton are usually scattered before being fossilised. In order to interpret them correctly, the palaeontologist must piece them back together, or at least work out which bits are which.

"This is difficult enough when you have modern relatives for comparison; but what if there's nothing alive today that's remotely like the extinct animal you need to analyse? It's exactly like doing a jigsaw puzzle without a picture."

This is what faces palaeontologists who study conodonts. Lead author David Jones, who carried out the study while at the University of Leicester, explains: "Earth's oceans teemed with conodonts for 300 million years; they were the most common vertebrates around, and they were the first to evolve teeth. In fact the conodont skeleton was all teeth: a basket of hacksaw-shaped blades which was extended out of the mouth to grab prey, behind which lay pairs of slicing blades and crushing teeth - a set of gnashers straight out of Alien."

Ancient marine rocks are often packed with hundreds or thousands of scattered conodont teeth, with many species jumbled up together.

"To make matters worse, within any one animal, teeth from different parts of the skeleton looked almost identical! Now we have a jigsaw puzzle with no picture, where each piece could go in different places. But just so it's not too easy, conodont teeth are also microscopic, "said Dr Purnell, of the Department of Geology.

Traditionally, experts would wrestle with this puzzle based on their previous experience and comparison with more complete skeletons, but researchers investigated whether there is another way?

For the new study, published in the latest issue of the journal Palaeontology, David Jones and Mark Purnell, from the University of Leicester, teamed-up with Peter von Bitter from the Royal Ontario Museum, Canada, to bring sophisticated statistical techniques to bear on solving this skeletal jigsaw. They used material from a 425 million year old rock deposit in Ontario, Canada which, unlike almost all other deposits in the world, preserves both scattered teeth and complete skeletons of conodonts. This material allowed them to compare the success rate of experts in placing the teeth in the correct positions within the skeleton, with the success rate of computer-based methods.

So how do the experts stack up against the machines? "Pretty well" says Jones. "This is reassuring for palaeontologists! but the computer-based approach did at least as well and was also consistent; experts disagreed amongst themselves, and less experienced palaeontologists, not surprisingly, made more mistakes.

"The statistical techniques therefore allow us to test and verify the conclusions drawn by palaeontologists, greatly increasing the confidence with which we can reconstruct the skeletons of extinct vertebrates. But it's not time to retire the experts; at least not yet..." say the researchers.
-end-
Notes to Editors:

1. The paper, "Morphological criteria for recognising homology in isolated skeletal elements: comparison of traditional and morphometric approaches in conodonts" by David Jones, Mark Purnell and Peter von Bitter is published in the current issue of Palaeontology. Copies of the paper can be obtained on request from David Jones or Mark Purnell (details below).

2. David Jones is currently at the School of Biological Sciences, Monash University, Melbourne, Australia

3. Palaeontology is published by the Palaeontological Association, a registered charity that promotes the scientific study of fossils. It is one of the world's leading learned societies in this field. For further information about the Association and its activities, or forthcoming papers of interest in Palaeontology, contact the Publicity Officer, Mark Purnell, publicity@palass.org

4. High resolution versions of the images below can be obtained from pressoffice@le.ac.uk

Issued by: University of Leicester press office: 0116 252 3335 pressoffice@le.ac.uk

Contact: David Jones: David.Jones@bristol.ac.uk; tel. +61(0)399051626
Mark Purnell, mark.purnell@le.ac.uk: 0116 252 3645

University of Leicester

Related Teeth Articles from Brightsurf:

Astronomers sink their teeth into special supernova
Astronomers using several telescopes at NOIRLab, including the Southern Astrophysical Research (SOAR) Telescope, have obtained critical data on a particular type of exploding star that produces copious amounts of calcium.

Researchers discover biomarkers of ALS in teeth
Mount Sinai scientists have identified biological markers present in childhood that relate to the degenerative and often fatal neurological disease called amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig's disease, according to a study published in the Annals of Clinical and Translational Neurology in May.

Brush your teeth to protect the heart
Brushing teeth frequently is linked with lower risks of atrial fibrillation and heart failure, according to a study published today in the European Journal of Preventive Cardiology, a journal of the European Society of Cardiology (ESC).

Piranha fish swap old teeth for new simultaneously
With the help of new technologies, a team led by the University of Washington has confirmed that piranhas lose and regrow all the teeth on one side of their face multiple times throughout their lives.

What wolves' teeth reveal about their lives
UCLA biologist discovers what wolves' broken teeth reveal about their lives.

These pink sea urchins have teeth that sharpen themselves
Sea urchins have five teeth, each held by a separate jaw in a circular arrangement at the center of their spiked, spherical bodies.

The secret strength of gnashing teeth
There's a method to finite element modeling for materials microarchitecture to make super strong glass.

No teeth cleaning needed: Crocodiles shed old teeth, grow new ones
Having one of the most powerful bites in the animal kingdom, crocodiles must be able to bite hard to eat their food such as turtles, wildebeest and other large prey.

Why deep-sea dragonfish have transparent teeth
Off the coast of San Diego, 500 meters under the sea, pencil-sized sea monsters grin pitch-black smiles because their mouths are filled with transparent teeth.

Brush your teeth -- postpone Alzheimer's
Researchers at the University of Bergen in Norway have discovered a clear connection between oral health and Alzheimer┬┤s disease.

Read More: Teeth News and Teeth Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.