Creatures started to go 'extinct' long ago, in the far distant past going back to when the first dinosaurs made their appearance on the earth, some 230 million years ago in the Triassic Period; we can trace the evolution of these creatures from the fossil records which have been discovered in Argentina and Brazil. In 2012 scientists have succeeded in recreating the life of dinosaurs like Tyrannosaurus Rex or T-Rex using the latest laser beam technology resulting in a conclusion that they hunted in deadly blood-thirsty packs. Why the dinosaurs along with numerous other creatures on Land, Sea, and Air became "Extinct" is an ongoing study for the scientists. Various theories, such as sudden climate change, and volcanic eruptions, are suggested for their extinction. Another popular theory among some scientists is that an asteroid such as the one that struck the Yucatan Peninsula in Mexico, causing an enormous crater about 180 kilometres or 111 miles wide, would have caused dust to blot out the sunlight like the volcanic eruptions did, and causing extremely cold weather for months or years. So whether it was climate change that made the climate drier and colder, volcanic ash or an asteroid blotting out the sun effecting photosynthesis and the growth of plants, or a combination of all of them contributing to these creatures becoming extinct, is still open to debate. One thing that is certain is that interference by humans upon creatures living before about 4 million years ago, either by hunting, or interfering with the habitat of these creatures did not occur, simply because humans did not exist before this time. The effect that man has had on the creatures that existed on earth since his appearance, as well as efforts to protect existing species is also outlined in this book "EXTINCT "