Across
- 1. from 230 million to 63 million years ago
- 4. Most leptons and anti-leptons annihilate each other. The universe is dominated by _______.
- 7. Sponges, multi-celled animals appear. Supercontinent Rodinia
- 9. approximately the last 63 million years
- 10. Hydrogen and helium atoms form.
- 12. The result of the universe expanding and cooling down during the Planck epoch
- 18. First humans, mammoths, mastodons, saber-toothed cats.
- 20. The first stars and quasars form due to gravitational collapse.
- 22. First deer, cats, pigs, tapirs, and rhinos, elephants, horses, owls, shrews, hedgehogs, and rabbits evolve.
- 23. Explosion of life forms. First shellfish, primitive fish, trilobites, corals, mollusks
- 24. the period in the evolution of the early universe when the fundamental interactions of gravitation, electromagnetism, the strong interaction and the weak interaction had taken their present forms, but the temperature of the universe was still too high to allow quarks to bind together to form hadrons
- 25. First mammals, dinosaurs, frogs, turtles, crocodyloformes.
- 27. Most hadrons and anti-hadrons annihilate each other, leaving behind ______ and anti-______
- 28. Australopithecus appears. First sheep, cattle, modern whales, bears, mice, rats, apes, monkeys, dogs, modern birds appear.
Down
- 2. First land plants, corals, Nautiloids. Ends in mass extinction
- 3. the period in the evolution of the early universe when, according to inflation theory, the universe underwent an extremely rapid exponential expansion
- 5. Widespread coal swamps. First reptiles, winged insects.
- 6. Sail-back reptiles. Amphibians abundant. Pangaea forms. Ends with mass extinction.
- 8. Abundant dinosaurs, first birds.
- 11. the period in the evolution of the early universe when the temperature of the universe was high enough to merge electromagnetism and the weak interaction into a single electroweak interaction
- 13. The temperature of the universe has cooled down enough to allow atomic nuclei to form via nuclear fusion.
- 14. / Oxygen build-up on Earth. First multi-cellular life
- 15. First flowering plants, snakes, crocodilians. K-T mass extinction at end kills dinosaurs, and others
- 16. First amphibians, sharks, bony fish, ammonoids, and spiders. Many fish.
- 17. from 544 million to about 230 million years ago
- 19. the earliest period of time in the history of the universe, from zero to approximately 10−43 seconds
- 21. The universe has cooled enough for quarks to form ______, protons, neutrons.
- 26. First insects, vascular plants on land.