Robert G. Hoehn has taught earth science, physical science, and biology in the Roseville Joint Union High School District of California since 1963. He uses wit and humor daily as an educational tool. Author of numerous publications, including Science Puzzlers from Jossey-Bass, he counts seven National Summer Science grants from the National Science Foundation among his many accomplishments.

• About the Author iiiAcknowledgments vIntroduction xiiiSection 1: Preserved Evidence of Past Life1 What Fossils Have to Say Fossil secrets 22 Long-Ago Life Forms Multicellular organisms 43 Footprints from the Past Fossil imprints 64 Early Wings Bird-dinosaur–link mystery 85 Two Steps Ahead of the Rest New lizard discovery 106 Dinosaur-Snacking Crocodile Super Croc 127 Awesome Dinosaur The Apatosaurus 148 Even More Dinosaurs Two massive ancient reptiles 169 Mast from the Past Protecting fossil bones 1810 North American Mammal Mystery Disappearing mammals 2011 Fossils on Hold Fossils alive and well 2212 Let’s Ban Man Human causes of extinction 24Challenge Activities (10 items) 26Section 2: Early Human Life on Earth13 New Face from an Old Skull Oldest human ancestor(?) 2814 Who Ate My Kangaroo? Early human appetites 3015 Early Artists Show Their Skill Art from the start 3216 Egyptian Cave Art Real or fake? 3417 Early Man Appears Iceman and Kennewick Man 3618 Keeping the Past Alive Ancient ruins’ preservation 38Challenge Activities (7 items) 40Section 3: Getting to Know the Lithosphere19 Leaving the Lava Behind 1 Mayon volcano (Philippines) 4220 Leaving the Lava Behind 2 Mt. Nyiragongo (Rwanda) 4421 Volcano Secrets Volcanics (Baja California) 4622 Earthquakes 1 Earthquake news 4823 Earthquakes 2 More earthquake data 5024 Nature’s Quake Predictors Geyser mystery 5225 Glacier Alert 1 All about glaciers 5426 Glacier Alert 2 More glacier information 5627 Inner Space Travel From erosion to caves 5828 Mapping in Outer and Inner Space Mapping techniques 6029 Global Positioning System Satellite Navigation Network 62Challenge Activities (11 items) 64Section 4: Listening to the Environment30 Chromium 6 on Trial A most harmful chemical 6631 Mercury Menace Mercury poisoning 6832 Global Warming Warning 1 Global warming trends 7033 Global Warming Warning 2 Global warming trends 7234 Ocean Currents and Weather El Niño/La Niña 7435 Pollution Problem Air pollution 7636 Pollution Solution Technology advancements 7837 Forever Organisms Preventing extinction 80Challenge Activities (9 items) 83Section 5: Ocean Features and Related Creatures38 Save the Coral Coral reef restoration 8639 Lost City Found Hydrothermal vents 8840 Island Under Water Submerged island 9041 Don’t Go Near the Water Beach pollution 9242 Fate of the Fish Pollution/Overfishing 9443 Microbes from Across the Sea Ballast water microbes 9644 Cormorants Under Siege A fisheries pest 9845 The No-Wimp Shrimp Mantis shrimp 10046 Jellyfish on the Rocks Fossilized jellyfish 10247 Anemone by the Sea Sea anemone 10448 Squid Freak from Down Deep New discovery 10649 Stingless Stingrays De-barbing stingrays 10850 Plight of the Sturgeon Sturgeon problem 11051 Predator Challenge Predator cautions 11252 The Sea Otter’s Dilemma Endangered species 11453 Sea Lions Take Charge Nuisance at sea 11654 A Whale of a Tale Ancient swimmers 118Challenge Activities (11 items) 120Section 6: What’s Happening in Space?55 Taking on the Universe Examining the universe 12456 New Planets in Town Recent finds 12657 Mars: A Watery World? Search for water 12858 Asteroid Probes Coming Up Asteroid data 13059 Eros: Space Mountain Asteroid Asteroid study 13260 Paranoid Rhymes with Asteroid Asteroid fears 13461 Twenty-Two and Counting Saturn surprise 13662 The Moons of Jupiter Recent discoveries 13863 Meteor Trails and Comet Tales Meteors/Comets 14064 Meteorite Mysteries Meteorite information 14265 From Stars to Galaxies Star data 14466 Telescopes and Beyond MAXIM/SOFIA 146Challenge Activities (12 items) 148Section 7: Life on Land and Water67 As the Worm Turns Worm discoveries 15268 It’s All About Ants Ant stories 15469 Insects Two Grasshopper/Cricket 15670 Where Have All the Froggies Gone? 1 Vanishing amphibians 15871 Where Have All the Froggies Gone? 2 Vanishing amphibians 16072 The California Condor Comeback 1 Condor rescue 16273 The California Condor Comeback 2 Condor rescue 16474 Rodent Roundup 1 Mostly rats 16675 Rodent Roundup 2 Meet meadow mouse 16876 The Smallest of Critters Mouse lemurs 170Challenge Activities (10 items) 172Section 8: What’s Up in Genetic Science?77 Genetic Review Genetic terms 17478 From One Gene to Another 1 A look at genes 17679 From One Gene to Another 2 A look at genes 17880 Designer Catfish “Customized” catfish 18081 Biotech Foods Genetically modified organisms 18282 Human Stem Cells Stem cell concerns 18483 Human Genome A chromosome gathering 18684 What About Cloning? Cloning issues 188Challenge Activities (8 items) 190Section 9: Timely Real-Life Topics of Concern85 Environmental Pollution 1 Student comments 19286 Environmental Pollution 2 Student comments 19487 The Decreasing Fish Population Student comments 19688 Whale Concerns 1 Student comments 19889 Whale Concerns 2 Student comments 20090 Dealing with Dolphins Student comments 20291 The Cold Facts About Cryonics Student comments 204Riddles for the Asking 207Answer Key 211Riddles Answer Key 231