About 320 million years ago, precursors of Pangea Laurussia (combined Scotland, Greenland, North America and Russia) and Gondwana ( which was the rest of the earth's land mass ) converged and made a Godzilla continent surrounded by the huge panthalassic ocean. The collisions of Laurussia and Gondwana raised a mountain belt, present-day remnants of which are the Appalachians along North America’s eastern coast and highlands in central Europe. By 135 million years ago (dang plate tectonics, you move slow ) the breakup of pangea was well under way. Rifting and seafloor spreading opened the nascent North Atlantic Ocean between North America and the old continent Gondwana, in which South America and Africa were still Jointed. So wasn't that nice …show more content…
I bored you with some continents, well some of you so since i'm nice let's skip to india's collision with Eurasia. Forty five million years ago, India crossed the equator in its rapid move towards Asia. Africa drew closer to Europe, narrowing the ancient Tethys Sea. And Gondwana breakup was completed when Australia split from Antarctica and drifted northward. Today, the folded straps of the Himalayas bear to witness India continuing collision with Asia, while the jostling of the African plate and the Eurasian Plate still causes the Alps to rise ( If you don”t know what Alps are they are the mountains near Italy and pretty much in Southern Europe) and the last vestige of the Tethys, the Mediterranean Sea to shrink. ANIMAL LIFE Pangea was a supercontinent 250 million years ago.
The supercontinent had many organisms like insects. Arthropods continued to diversify during the Permian Period to fill the niches opened up by the more variable climate. True bugs, with mouthparts modified for piercing and sucking plant materials, evolved during the Permian. Other new groups included the cicadas and beetles.There were also mammals,during pangea’s time period the Traversodontidae, a family of plant-eating animals that includes the ancestors of mammals. The ocean surrounding pangea was called Panthalassa, little is known about the huge Panthalassic Ocean, as there is little exposed fossil evidence available. Fossils of the coastal water on the continental shelf indicates that reefs were large diverse ecosystems with sponge,ammonites,similar to the modern nautilus, were common, as were brachiopods. There still was many sharks and manta …show more content…
rays. THE FUTURE EARTH DEPENDING ON THE PLATE TECTONICS If present plate movements continue for 100 million years, the atlantic will become the world’s largest ocean, far surpassing the shrunken pacific.
Africa will grind into Europe, closing the Mediterranean and building new mountains, while continued rifting will turn Africa’s rift valley into a seaway. Other crustal movements will shave a sliver of california from the North American coast and drag Austrlia toward southeast Asia, folding the interviewing islands into collision mountains. New plate movements will begin, and subduction trenches may develop along the Atlantic coasts of the Americans and around Australia, as old, dense sea floor laden with sediments, sinks into the mantle ( well we are dead in 100 million years if we are not already dead from our pollution and wasting our resources or nuclear war like Fallout 4 just look up some videos on youtube of Fallout 4 and you will know what i'm talking about ). Volcanic island arcs and tall coastal mountains will appear on the landward sides of the trenches. Now 250 million years from now you won't believe it, but that's only if the plate movements continue. Continued subduction of the ocean may close the atlantic and indian oceans, drawing the continents together in a single immense land mass sprawling across half the globe a new Pangea. Ranges of folded mountains heaved up by the continental collisions will mark former coastlines. The Pacific ocean will once again be dominant, still spreading outward from central rifts
and descending into subduction trenches that ring the supercontinent. Part of the now-ancient African rift ocean will remain trapped within the huge land mass-an ocean penned in by plate movements, much like the Mediterranean today.
A significant portion of New England was formed as a result of an accretionary orogen. Southeastern New England is marked by a series of terranes that accreted onto the Laurentian supercontinent during the Silurian and Devonian. The Terranes of Gander, Nashoba, Avalon, and Meguma are present from west to east in eastern Massachusetts and all of are Gondwanan provenance. Their modern-day juxtaposition suggests that the marginal Gondwanan micro-continents collided sequentially from west to east, expanding the Laurentian continent with each respective collision. As each subsequent plate collided, an intervening subduction zone died and a new subduction zone was created to the east. The oblique collision of the Avalon Terrane into Laurentia followed the accretions of the Gander and Nashoba Terranes and preceded the accretion of Meguma. The collision was marked by uplift, mylonitic metamorphism, and calc-alkaline Nashoba plutonism as the Iapetus Ocean subducted under the Nashoba and eventually the Avalon collided obliquely into the continental margin.
15. The pictures above show how the continents on Earth’s surface have changed position over a very long period of time. What explains this change? (S6E5e, f)
Earthquakes are a natural part of the Earth’s evolution. Scientific evidence leads many geologists to believe that all of the land on Earth was at one point in time connected. Because of plate tectonic movements or earthquakes, continental drift occurred separating the one massive piece of land in to the seven major continents today. Further evidence supports this theory, starting with the Mid-Atlantic ridge, a large mass of plate tectonics, which are increasing the size of the Atlantic Ocean while shrinking the Pacific. Some scientists believe that the major plate moveme...
To set the stage, we must go back 270 million years ago when a majority of the earth’s land masses were collected together in a single continent, a supercontinent, named Pangaea (Encyclopedia Britannica, 1). Historian Alfred Crosby explained that this collected all of earth’s land based biology into a single place, creating a single Darwinian “arena for competition” (Crosby, 1). Or in other words, one big evolutionary pot. Crosby also explains that 180 million years ago, Pangea split into two major land masses, what is now the Americas in the Western Hemisphere as one land mass and Euro-Asia and Africa as the second lass mass (Crosby, 1). What was once a single evolutionary pot, was now two, allowing for plant and animal life to take different evolutionary paths. These two worlds remained relatively separate from each other until the arrival of Christopher Columbus and other European explorers. That contact between the old world and the new world brought two distinct evolutionary arenas crashing into each other and returned a majority of the earth’s landmass into a single Darwinian pot, (Crosby, 1) This was Crosby’s re-knitting of the torn “seams of Pangaea.”
Americas by 14,000 ago” (O’Brien 12), after large portions of North America encountered the last ice age, which
After the Laramide orogeny things were still happening, just as always with Earth. Something is always changing even if it is not detectable day by day. Due to the Farallon Plate subducting there was a suction like effect going on because of the water that was being taken in with it (Humphreys). This would cause the North American plate to become weak and unstable, because it was being hydrated. This eventually would result in large plateaus and large amounts of uplift (Humphreys). There are many things that have been going on through out this time period but it all turns around and creates and shapes the earth into what it is today as well as what it will be in the future.
The theory concluded that around 200 million years ago, the heavy Pacific Plate collided with the lighter North American Plate, and started sliding underneath, a process known as subduction. This continued for 100 million years, until some 20 million years ago, when the Pacific Plate was forced to change direction and started sliding north, creating the San Andreas Fault. Most of California’s population sits on the west side of the fault, the Pacific plate, while the rest of North America is sitting on the east side of the fault, the North American
How did the Atlantic System affect Europe, Africa, and the Americas? (The Earth and Its Peoples, 500)
Many years ago, continental drift took the Old and New Worlds apart, dividing North and South America from Eurasia and Africa. That disconnection lasted so long that it fostered divergent evolution; for example, the growth of rattlesnakes on one side of the Atlantic. Subsequently 1492, human travelers in part altered this propensity. Their reestablishment of relationships through the merge of Old and New World plants, creatures, and diseases, frequently known as the Columbian Exchange. It’s one of the most spectacular and significant ecological events of the past millennium.
The species A. afarensis is one of the better known australopithecines, with regards to the number of samples attributed to the species. From speculations about their close relatives, the gorilla and chimpanzee, A. afarensis’ probable social structure can be presumed. The species was named by Johanson and Taieb in 1973. This discovery of a skeleton lead to a heated debate over the validity of the species. The species eventually was accepted by most researchers as a new species of australopithecine and a likely candidate for a human ancestor.
analysis on how the Atlantic became known as the Atlantic because of the presence of
They ruled the world before the time of the dinosaurs, from the Cambrian Period to the
Han, J., Zhang, Z. F., & Liu, J. N. (2008). A preliminary note on the dispersal of the Cambrian Burgess Shale-type faunas. Gondwana Research, (1), 269-276. doi:10.1016/j.gr.2007.09.001
...t of laurasia, just like most of the other plates. North America,Europe, and Green land all used to be connect because of Pangea ( as mentioned earlier). But when everything started to separate, first europe, then green land, and lastly the North American plate. After pangea was no more and the plates all started moving, the continents started going their own ways, there fore putting the continents where they are today.
Evolution is a theory that argues that all organisms alive on earth today share a common ancestor. It is thought that through generations, specific changes or adaptations were established in species in order to help them survive, reproduce, and raise offspring. But how are we certain that these changes occurred? Today, there is an abundant amount of research evidence that suggests that anatomical and physiological alterations occurred to species that caused them to turn from aquatic animals to terrestrial animals, allowing them to survive different environmental conditions. The following are several gradual changes an aquatic organism must go through in order to move to land and adjust to its new terrestrial habitat: circulatory and most importantly respiratory systems must be improved, structural adaptations should be modified, development of a skeletal system to protect the body and organs, and an adjustment of the senses must also occur.