Have you seen a dodo bird recently? Do you have mastodons playing in your back yard? Not likely-- these species are extinct! In Earth's 4.5 billion-year history, more than 5 billion species have gone extinct, some of them at the same time. In EXTINCTION: WHAT HAPPENED TO THE DINOSAURS, MASTODONS, AND DODO BIRDS? kids ages 9 to 12 learn about the detective work scientists perform to find out why mass extinctions happen...Try these hands-on STEM projects!...

Investigate how an asteroid vanquished the dinosaurs 66 million years ago. Join scientists as they drill into the impact crater and, for the first time, reconstruct the hell on earth that unfolded in the minutes, hours, and months after the impact.

For hundreds of thousands of years Great Auks thrived in the icy seas of the North Atlantic, bobbing on the waves, diving for fish and struggling up onto rocky shores to mate and hatch their fluffy chicks. But by 1844, not a single one of these magnificent birds was alive. Award-winning author and illustrator Jan Thornhill tells the tragic story of these birds that "weighed as much as a sack of potatoes and stood as tall as a preteen's waist." Their...

In End Times, Walsh examines threats that emerge from nature and those of our own making: asteroids, supervolcanoes, nuclear war, climate change, disease pandemics, biotechnology, artificial intelligence, and extraterrestrial intelligence. Walsh details the true probability of these world-ending catastrophes, the impact on our lives were they to happen, and the best strategies for saving ourselves, all pulled from his rigorous and deeply thoughtful...

Packed with ingenious scientific work and spectacular fossils, Nova's Ice Age Death Trap reveals intimate secrets of the life and death of North America's most exotic and extreme creatures: mastodons, saber tooth cats and camels, giant bison with six-foot horns, and ground sloths as big as elephants. Most tantalizing of all, the excavation, organized by the Denver Museum of Nature and Science, unearths startling and controversial evidence of what...

"Most days, Sarya doesn't feel like the most terrifying creature in the galaxy. Most days, she's got other things on her mind. Like hiding her identity among the hundreds of alien species roaming the corridors of Watertower Station. Or making sure her adoptive mother doesn't casually eviscerate one of their neighbors. Again. And most days, she can almost accept that she'll never know the truth--that she'll never know why humanity was deemed too dangerous...