Dinosaurs & Life
What group of reptiles ruled the land during the Mesozoic Era?
Dinosaurs
What tiny shelled plankton fossils were used as markers of geologic time?
Foraminifera (forams)
The KT boundary marks the end of what era?
The Mesozoic Era
What father and son team connected the iridium layer to an asteroid impact?
Luis and Walter Alvarez
About how wide was the asteroid that struck Earth?
10 kilometers
What flying reptiles had wingspans up to 40 feet?
Pterosaurs
What preserved remains of ancient life help scientists study the past?
Fossils
The KT boundary marks the beginning of what era?
The Cenozoic Era
In what Italian town did scientists first notice the mysterious clay layer?
Gubbio
The asteroid’s impact released the energy of about how many nuclear bombs?
100 million nuclear bombs
What fierce marine predators prowled the seas during the Mesozoic?
Mosasaurs
What happened to the foraminifera species at the KT boundary?
Almost all of them disappeared
What rare element, common in asteroids, was found in the clay layer?
Iridium
What Dutch geologist studied the KT boundary in Spain?
Jan Smit
What massive natural disaster moved giant boulders in Texas after the impact?
A tsunami
What small, adaptable group of animals survived the extinction and later flourished?
Mammals
What mineral shows microscopic damage caused by a massive impact?
Shocked quartz
About how many million years ago did the KT boundary form?
65 million years ago
What graduate student investigated unusual deposits in Texas that supported the impact theory?
Alan Hildebrand
What essential plant process stopped when sunlight was blocked?
Photosynthesis
What plants briefly dominated after the extinction, creating a “fern spike”?
Ferns
What glassy beads formed when vaporized rock cooled and fell back to Earth?
Spherules (or tektites)
What site in Mexico was the location of the impact crater?
Chicxulub (Yucatán Peninsula)
What geologist, while searching for oil, identified the buried crater in Mexico?
Glen Penfield
Scientists say survival after the extinction wasn’t only about being the fittest, but also about being what?
The luckiest