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The southern supercontinent Gondwana (originally Gondwanaland) included most of the landmasses which make up today's continents of the southern hemisphere, including Antarctica, South America, Africa, Madagascar, India, Australia-New Guinea, New Zealand, and New Caledonia. (The remaining continents at that time -- North America and Europe- Asia -- were also joined, forming the northern supercontinent, LaurasiaLaurasia was a supercontinent that broke off from the Pangaean supercontinent in the late Mesozoic era. Laurasia divided into Eurasia and North America around 200 million years ago. The southern supercontinent created is called Gondwana. See also Alfred W.)
Although Gondwana was centered roughly where Antarctica is today (at the extreme south of the globe), the climate was generally mild. During the MesozoicThe Mesozoic is one of four (sometimes more) geologic eras. The division of time into Eras dates back to the 19th century. The Mesozoic includes three Geologic Periods; from oldest to youngest, the Triassic, Jurassic and Cretaceous. It extended from rough, average global temperatures were considerably warmer than they are today. Gondwana was then host to a huge variety of flora and fauna for many millions of years.
The supercontinent began to break up in the late JurassicThe Jurassic period is a major unit of the geologic timescale that extends from about 135 million years BP at the end of the Triassic to 195 million years BP at the beginning of the Cretaceous. As with other geologic periods, the rock beds that define the (about 160 million years ago) when Africa became separated and began to drift slowly northwards. The next large block to break away was India, in the early CretaceousThe Cretaceous period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic period (about 135 mya) to the beginning of the Paleocene epoch of the Tertiary period (65 mya). The end of the Cretaceous also defines the (about 125 million years ago). New Zealand followed about 80 million years ago, only about 15 million years before the Cretaceous-Tertiary extinction eventThe Cretaceous-Tertiary (KT) extinction event also known as the KT boundary (from German: , was a period of extremely frequent extinction of species, about 65. 5 million years ago. It corresponds to the end of the Cretaceous period and the beginning of th wiped out about 50% of all species on the planet, most notably the dinosaurSaurischia Ornithischia The dinosaurs were a diverse and long-lived superorder of prehistoric reptiles. What is a dinosaur? Definition Dinosaurs are a superorder of reptiles that first appeared approximately 230 million years ago. A few lines of primitives.
As the age of mammalsThe Tertiary period is one of the major divisions of the geologic timescale, from the end of the Cretaceous period about 64 million years ago to the start of the Quaternary period about 1. 6 million years ago. The Tertiary includes five geologic epochs th got underway, the continent of Australia-New Guinea began to gradually separate and move north (55 million years ago), rotating about its axis to begin with, and thus retaining some connection with the remainder of Gondwana for a considerable time.
About 45 million years ago, the Indian subcontinentThe Indian subcontinent is the peninsular region of larger South Asia in which the nations of India, Bangladesh, Pakistan, Sri Lanka as well as parts of Nepal, Bhutan, Myanmar and some disputed territory currently controlled by China are located. It is al collided with Asia, forcing the crust to buckle and forming the Himalayas. At about the same time, the southern-most portion of Australia (modern Tasmania) finally separated from what is now Antarctica, allowing ocean currents to flow between the two continents for the first time. This in turn produced cooler and dryer climates on the two landmasses.
Far more significant as a world climatic event, however, was the separation of South America sometime during the Oligocene, perhaps 30 million years ago. With the opening of Drake Passage, there was now no barrier to force the cold waters of the Southern Ocean north, to be exchanged with warmer tropical water. Instead, a cold circumpolar current developed and Antarctica became what it is today: a frigid continent which locks up much of the world's fresh water as ice. Sea temperatures dropped by almost 10 degrees, and the global climate became much colder.
About 15 million years ago, New Guinea began to collide with southern Asia, once again pushing up high mountains, and more recently still, South America became joined to North America via the Isthmus of Panama.
The continent was named by Eduard Suess after Gondwana, a region of eastern India where some of the geology of the ancient continent was determined.
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