Mighty predator that ruled the ocean with the most powerful bite

Mighty predator that ruled the ocean with the most powerful bite

 

Scientists now have a wealth of information about jawed vertebrates thanks to discovering the Dunkleosteus terrelli.

Its existence can be traced back to 400 million years ago when it easily lorded over the ocean kingdom. With a formidable length of 33 feet, awesome weight of 4 tons and deadly bladed jaws, it easily ate its way up and through the food chain.

Its bite force is reckoned to equal 11000 pounds that was concentrated into a select area with a super powered force of 80000 pounds per square inch.

The fish is classified as a placoderms that included a wide variety of fishes that were armored and that reigned supreme over the population of aquatic ecosystems. This species dates back to the period of the Devonian that goes as far back as 415 to 360 million years ago.

While scientists have been familiar with the existence of this high powered predator, a fresh lot of important information will soon be available in the Royal Society journal Biology Letters on November 29.

The picture one forms in the mind of this creature defies description: extremely rapid opening of the mouth that generated a powerful suction, effortlessly sucking in prey into its mouth. An awe-inspiring and unique combination of a powerful and fast bite that is not easily found among creatures.

A co-author of the soon to be published paper, Mark Westneat, Curator of Fishes at The Field Museum reveals that he found this feature of a fast and powerful bite particularly interesting. This has been enabled, he says, because of the superb and innovative engineering layout of the skull and mouth muscles. The presence of this trait recognizes the fish as a primary authentic "apex predators seen in the vertebrate fossil record."

A particularly recognizable feature of this fish is its bladed jaws. One of the first vertebrates to be invested with this feature, it allowed for an enormously powerful bite alongwith ruthlessly rapid fragmentation of the prey before being sucked into the mouth.

Such an indepth understanding of the fish by scientists was made possible with their efforts to work on the fossilized skull of a Dunkleosteus terrelli. The scientists then took backward steps to understand how the muscles came to be.

Scientists were able to fashion a biomechanical model that displayed the force and motion of the fish's jaw, the superbly kinetic skull backed by a advanced mechanism of four rotational joints that complemented each other functionally. Scientists are able to state confidently that this creature surpasses the most powerful bites of any fish and any animal including the demonic Tyrannosaurus Rex.

This powerful creature was able to choose its prey among the vast range of aquatic animals that included the formidable shark. Other creatures included arthropods and ammonoids.

This is attested to by Philip Anderson, at the Department of Geophysical Sciences at the University of Chicago who led the research. He observes that this formidable creature could attack and assume just about any inhabitant of the environment. Its features, particularly the bladed jaws were way ahead of its time particularly since we know that it was then seen in sharks after 100 million years.

The study apart from evoking our interest in a truly magnificent fish species has highlighted the relevance of mechanical engineering theory. While we can never have the privilege of actually watching this animal, Anderson says, technology allows us to go back in time and obtain useful impressions of how these creatures lived and their significant body features.

Mass Extinction 250 Million Years Ago Sparked Dramatic Shift To Complex Marine Ecosystems

ScienceDaily: Mass Extinction 250 Million Years Ago Sparked Dramatic Shift To Complex Marine Ecosystems

Mass Extinction 250 Million Years Ago Sparked Dramatic Shift To Complex Marine Ecosystems

The earth experienced its biggest mass extinction about 250 million years ago, an event that wiped out an estimated 95% of marine species and 70% of land species. New research shows that this mass extinction did more than eliminate species: it fundamentally changed the basic ecology of the world's oceans.

In the Cretaceous about 80 million years ago -- well after the end-Permian mass extinction -- the ocean floor was dominated by complex ecosystems that had largely displaced the simple ecosystems. This photograph of a Field Museum diorama of the ocean floor during the Cretaceous shows many free-swimming, complex organisms, including the large ammonoid (in the center of the image) and the long nautiloids (with handlike ends). In addition, the ocean floor is littered with mobile clams and snails. (Photograph of Field Museum diorama by Ron Testa, courtesy of The Field Museum)

Ecologically simple marine communities were largely displaced by complex communities. Furthermore, this apparently abrupt shift set a new pattern that has continued ever since. It reflects the current dominance of higher-metabolism, mobile organisms (such as snails, clams and crabs) that actually go out and find their own food and the decreased diversity of older groups of low-metabolism, stationary organisms (such as lamp shells and sea lilies) that filter nutrients from the water.

So says research published in Science on November 24, 2006. An accompanying article suggests that this striking change escaped detection until now because previous research relied on single numbers--such as the number of species alive at one particular time or the distribution of species in a local community--to track the diversity of marine life. In the new research, however, scientists examined the relative abundance of marine life forms in communities over the past 540 million years.

One reason they were able to do this is because they tapped the new Paleobiology Database ( http://www.pbdb.org), a huge repository of fossil occurrence data. The result is the first broad objective measurement of changes in the complexity of marine ecology over the Phanerozoic.

"We were able to combine a huge data set with new quantitative analyses," says Peter J. Wagner, Associate Curator of Fossil Invertebrates at The Field Museum and lead author of the study. "We think these are the first analyses of this type at this large scale. They show that the end-Permian mass extinction permanently altered not just taxonomic diversity but also the prevailing marine ecosystem structure."

Specifically, the data and analyses concern models of relative abundance found in fossil communities throughout the Phanerozoic. The ecological implications are striking. Simple marine ecosystems suggest that bottom-dwelling organisms partitioned their resources similarly. Complex marine ecosystems suggest that interactions among different species, as well as a greater variety of ways of life, affected abundance distributions. Prior to the end-Permian mass extinction, both types of marine ecosystems (complex and simple) were equally common. After the mass extinction, however, the complex communities outnumbered the simple communities nearly 3:1.

The other authors are Scott Lidgard, Associate Curator of Fossil Invertebrates at The Field Museum, and Matthew A. Kosnik, from the School of Marine and Tropical Biology at the James Cook University in Townsville, Queensland, Australia.

"Tracing how marine communities became more complex over hundreds of millions of years is important because it shows us that there was not an inexorable trend towards modern ecosystems," Wagner said. "If not for this one enormous extinction event at the end of the Permian, then marine ecosystems today might still be like they were 250 million years ago."

These results also might provide a wake-up call, Wagner added: "Studies by modern marine ecologists suggest that humans are reducing certain marine ecosystems to something reminiscent of 550 million years ago, prior to the explosion of animal diversity. The asteroid that wiped out the dinosaurs couldn't manage that."

Lidgard added, "When Pete walked into my office with his preliminary results, I simply couldn't believe them. Paleontologists had long recognized that ecosystems had become more complex, from the origin of single-celled bacteria to the present day. But we had little idea of just how profoundly this one mass extinction--but not the others like it--changed the marine world."