Which Continents Can You Find The Same Animal Fossils On

Latitude On maps, lines of longitude and latitude separate the earth up. The lines that run from due east to westward are called latitude. They kickoff with a line right around the centre of the world called the equator. This is zero degrees latitude. As you go due north and due south from this line, the numbers increase until you get to the North and S Poles at 90 degrees. Anything farther south or due north of lxx degrees latitude is in the Polar Regions or the polar circle. South Eastern Australia was 75 degrees southward. And and so, because they lived over a hundred million years ago, the dinosaurs we find in Due south Eastern Commonwealth of australia are chosen polar dinosaurs.

How do we know that Australia has drifted?
The continents we know today take drifted a long mode from where they started as one big continent called Pangea. But how tin can we tell that the continents started as a one big land mass and slowly moved apart? > click to run across ABC Scientific discipline Continental Drift animation.

Rivers of ice, called glaciers, cut marks into rock with the boulders that they slowly elevate along with them. Ancient rocks, now in the torrid zone, have these marks on them. Glaciers can't form in the hot tropics, and then these rocks must have once been thousands of kilometers away in colder parts of Earth. Click here to read more about the > Floating Continent

Fossils from many millions of years ago as well show that 1 large continent had once existed and then cleaved apart. The fossils of the same ancient plants and small dinosaurs are found on different continents.

Did they cross the oceans to get there?
No. they didn't. Scientists accept noticed that similar plants and animals have left fossils on land masses separated by large oceans. Exactly the same brute or plant tin't have evolved on dissimilar continents. Studies likewise showed that the shape of the continents fit roughly together similar a jigsaw puzzle and the rocks on 1 border match the rocks on the other.

The trouble with this idea was that for a long time no-one could explain how the continents moved and and so bear witness it. Eventually, some scientists came upwards with a theory chosen Plate Tectonics. To read more detail almost Plate Tectonics, click here.

The continents are moving around on huge plates that are slowly pushed upwards from nether the body of water and crushed underneath mount ranges. The sea floor spreads and moves the continents apart. But how did they prove information technology? First you accept to sympathise a little bit about magnetism.

Magnetism
The World is similar an enormous magnet. The reason that compasses point Due north is that compasses have magnets in them that are attracted to the bigger magnet of Earth. If you think of the Earth as a big magnet you can imagine the tiny magnet in a compass existence attracted to the opposite end of the big magnet that is World. This opposite stop is the North Magnetic Pole. So a compass always points N.
Only the strange thing is that if you went back in time about a half a one thousand thousand years your compass would indicate South.

Shifting poles
For reasons that no-i fully understands, the World'due south magnetic poles slowly get weaker and then completely modify, on boilerplate, every half a million years or so. Right now nosotros are in the time of the magnetic field getting weaker and it'southward predicted that the poles volition reverse again some time in the next thousand years.

Merely how can we tell that the magnetic poles have reversed in the distant past?
Sure types of rock get magnetised when they are formed. Molten stone is imprinted with the magnetic field of the moment when it cools. It's a bit similar a photograph capturing the light of one moment in time. The rock takes a magnetic photograph at the moment it cools down. If it's heated up and cooled again, the magnetism will change to the magnetic field at that particular moment. At beginning, scientists were confused by the magnetism in aboriginal rocks pointing in the opposite management, only came to realise that all the rocks of a certain age, all over the earth, showed the aforementioned direction, proving that the Earth's magnetic poles sometimes completely contrary.

Magnetic strips on the sea floor
Once scientists knew about the irresolute of Globe's magnetic poles, they could work out how many times it had happened and when. The theory of continents being pushed apart could exist proved if the magnetism recorded in the rocks showed that molten rock was spreading abroad from the cracks in both directions. The final time that the poles were reversed was half a million years ago. The rocks on both sides of the crack, at the altitude they should have moved in a half a million years, should have the aforementioned sort of magnetism. And they practice. If you lot get further back to the previous time the poles reversed and look further away on either side of the ridge, once again you lot find strips of rock that record the reverse polarity. The continents actually are moving and it's been recorded by strips of different magnetism in the rocks on the sea floor.

Bank check out these ABC sites for more information on Pole Shifting

Journey to eye of pole-shifting Globe
" Latest computer simulations of the Earth's deep interior, provide insights into the operation of the 'geodynamo' and the occasional reversal of Earth's magnetic field…"
https://www.abc.net.au/science/news/stories/s101783.htm

Flipping over the Dominicus
American enquiry has found a reason why the Sun flips its magnetic poles every eleven years.
https://world wide web.abc.net.au/science/news/infinite/SpaceRepublish_574458.htm

Source: https://www.abc.net.au/science/ozfossil/ageofreptiles/continental/default.htm

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