When did the Mesozoic begin & end? What’s its nickname? The Mesozoic era began 252 million years ago and ended 66 million years ago. Its is also known as the “Middle Life”. What was the climate? Well it was definitely much warmer than today. The polar ice caps didn’t even exist. The carbon dioxide rised. And it captured the planets heat. What was the shape and location of the continents? It seemed like a large blob of continents. To me, it looked like dinosaur ready to chomp on its pray. What were the major changes to landforms? There was a very important change and that was the breakup of the supercontinent. It changed into the seven continents that we now have today. When this was happening, Antarctica was not at the south pole and was not covered in ice. What were the major changes to living things? During this part in the era, the recent mass extinction knocked out 90% of most species, and then the T-Rex & the Triceratops took over the landscape. What happened at the end of the time period? The climate fortunately began to cool during the cretaceous period but may have risen near the end. The Mesozoic era was very important because it was the era just before humans started to live on earth. So if something different might have happened then humans may have not existed.