Giant fossil sea scorpion bigger than man
November 21, 2007
Mock up of fossil sea scorpion, compared to man. Credit: Simon Powell
The discovery of a giant fossilized claw from an ancient sea scorpion indicates that when alive it would have been about 2.5 meters long, much taller than the average man.
This find, from rocks 390 million years old, suggests that spiders, insects, crabs and similar creatures were much larger in the past than previously thought.
Dr Simon Braddy from the Department of Earth Sciences at the University of Bristol, co-author of an article about the find, said, ‘This is an amazing discovery. We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches, and jumbo dragonflies, but we never realised, until now, just how big some of these ancient creepy-crawlies were.’
The research is published online today in the Royal Society’s journal Biology Letters. The claw was discovered by one of Dr Braddy’s co-authors, Markus Poschmann, in a quarry near Prüm in Germany.
Poschmann described finding the fossil: "I was loosening pieces of rock with a hammer and chisel when I suddenly realised there was a dark patch of organic matter on a freshly removed slab. After some cleaning I could identify this as a small part of a large claw. Although I did not know if it was more complete or not, I decided to try and get it out. The pieces had to be cleaned separately, dried, and then glued back together. It was then put into a white plaster jacket to stabilise it."
The claw is from a sea scorpion (eurypterid) Jaekelopterus rhenaniae that lived between 460 and 255 million years ago. It is 46 centimetres long, indicating that the sea scorpion to which it belonged was around 2.5 metres (8 feet) long – almost half a metre longer than previous estimates for these arthropods and the largest one ever to have evolved.
Eurypterids are believed to be the extinct aquatic ancestors of scorpions and possibly all arachnids.
Some geologists believe that giant arthropods evolved due to higher levels of oxygen in the atmosphere in the past. Others, that they evolved in an 'arms race' alongside their likely prey, the early armoured fish.
‘There is no simple single explanation’, explains Braddy. ‘It is more likely that some ancient arthropods were big because there was little competition from the vertebrates, as we see today. If the amount of oxygen in the atmosphere suddenly increased, it doesn't mean all the bugs would get bigger.’
Source: University of Bristol
Feb 05, 2009 |
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" when alive it would have been about 2.5 meters long, much taller than the average man."
long is NOT tall! i could still smash it's face in under the heel of my boot. that thing was not taller than a person who is 5'5''. i know , because i went back in time to find out. whose tuff now?
A new theory about:
Why insects have small bulks?
Before explanation of my new theory, I point out to those theories which have been presented before on this respect.
Exoskeleton theory:
Insects have exoskeleton and this theory point out that this skeleton isn't able to grow more actually, the insect is imprisoned inside this skeleton and isn't able to get larger.
Defects of this theory: All of arthropod owns exoskeleton, and some of them like crabs are able to own rather large body which is discordant with this theory. On the contrary, there are some insects that own softer exoskeleton, but again aren't able to enlarge. Also in the past (250 million years ago), there were insects that owned big bodies (like dragonfly by length of 75 cm) and this theory can't explain the reason of their existence. Because they owned hard exoskeleton too but they were able to enlarger!
Respiratory system theory:
Insects respiratory system comprise thin and capillary tubes called tracheae that supplies oxygen directly through existent pores on the body, to all insect bodies interior cells. That means, opposite other animals, oxygen isn't been carried by blood. It flows through inside of tracheas by means of propagation phenomenon, and reaches cells. This theory says that the propagation of oxygen inside the cells, is possible only in short intervals and if insects have large body, the length of tracheas will lengthen and oxygen can not reach cells. So insects are forced to own small body.
About existence of large insects in the past, this theory predicts the existence of high percentage oxygen in earth's atmosphere. According to this theory, atmosphere's oxygen amount, 250 million years ago, was higher than the oxygen, would make it possible the propagation of it through the long tracheas of insects. Therefore insects at that time were able to be longer than present insects.
Defects of this theory:
250 million years ago, there were plants from the class of Horsetails and Club moss as the shape of very big trees. But today, the same plants exist only in very small size of some centimeters. Botanists believe that high consistency of atmosphere's carbon de oxide (CO2) is the reason of existence of giant Horsetails and Club moss at that time.
You consider that entomologists predict a high consistency of oxygen and botanists predict a high consistency of CO2 for 250 million years ago. These two have confliction with each other.
This was a brief of theories existing in this respect.
My new theory, in this respect:
Blood circulation system theory:
My theory is based on animals' blood circulation system. The theory compares the power and evolution of blood circulation system for animals and expresses the relation between bulk largeness and power of blood circulation system. According to this theory as much as blood circulation system is stronger and complete, animals' bulk can be larger (bigger). Insect's blood circulation system is too incomplete and there are no blood vessels. Insect's bodies, with lack of blood vessels, aren't able to supply blood consisting nutrition to remote cells, so their body are forced to be small.
In this theory air pressure and gravity, are two physical factors that have impact on function of blood circulation system. The most effort of blood circulation system is used to conquest on gravity. As much blood circulation system is strong, is more able to conquest on gravity and send blood upper into animals' brain. Consequently, animal is able to enlarge more and taller. For example, elephants and giraffes, who own the most evoluted and strongest blood circulation system, are the largest and tallest ones among the animals.
For possibility of existence of insects whit big bodies and other big animals like dinosaurs and mammals in the past, this theory predicts a light gravity at that time. According to this theory, the amount of gravity in the past have been less than the present time, so blood circulatory system of animals was able to conquest better on it and enlarge animals body but along the time, gravity has been increasing and animals are forced to make smaller their body sizes.
As you know, there are some theories such as strike of meteorites or activity of volcanoes for extinction of dinosaurs, which each one has a lot of defects. It has been said ice ages for extinction of mammoths and a lot other theories for other extinctions. My new theory is able to answer all of these questions as a case of a theory and no need to state a different theory for each of these matters. This is my theory's name:
"The relation between gravity and evolution"
This theory is able to answer many questions about animals and plants and their extinction, which haven't been answered yet.
This theory is organized as cast of several articles that the sun of these articles now available as a book. The title of this book is "The theory of gravity increase". It's ISBN is 8-04-7061-964 in 1999 and have 120 page. It's English translation can be found on following site:
http://www.geocit...age.html
Ramin Amir mardfar