Questions for ‘The end of the dinosaurs appears to have come in springtime’

illustration of a dinosaur fleeing a massive flood

The Chicxulub asteroid impact off the coast of Mexico occurred about 66 million years ago. It triggered devastating flooding at a site in North Dakota (illustrated). This dino-killing impact took place in spring, data now suggest.

Joschua Knüppe

To accompany The end of the dinosaurs appears to have come in springtime

SCIENCE

Before Reading:

  1. Right now, is it spring, summer, autumn or winter where you live? What is an example of a country currently experiencing a different season from yours? Explain how the tilt of the Earth’s axis causes the northern hemisphere to experience summer while the southern hemisphere experiences winter and vice versa. Draw a picture if you prefer. If you aren’t sure, then do a quick internet search first. (Here’s one option, from NASA.)
  2. What do you know about the cause of the dinosaurs’ mass extinction? List some species you know of that went extinct. What does it mean for a species to become “extinct?” 

During Reading:

  1. In which U.S. state is the Tanis site located?
  2. Where did the Chicxulub asteroid impact occur? By knowing the season during which that impact happened, how might scientists better understand why some species survived? During what season is the impact believed to have occurred for the northern hemisphere? What would that be for the southern hemisphere?
  3. What year did scientists first discover the Tanis fossil site? Approximately how long after the Chicxulub impact are the fossilized creatures believed to have died at this site? What do scientists believe caused the “tiny round shapes” on some fish fossils unearthed there?
  4. How are the fish bones described in this study similar to tree rings?
  5. From which two species of fish did Melanie During analyze fossilized bones? From where on the fish did these bones originate?
  6. How many years have passed since the impact?

After Reading:

  1. Describe the structural feature of the fossilized bones that scientists in this study analyzed to determine the season of the impact. According to this article, what environmental factors affect the development of these features? Besides the season of their death, what else might a scientist learn about these creatures by studying their bones? Come up with one way this feature might give clues about the fossilized creature’s age, life cycle or the climate in which the creature lived.
  2. What types of species were more likely to survive the impact? Search the article for examples of characteristics of surviving species. Then use those characteristics to design an imaginary species that would have had a decent chance of survival. For example, is your fictional species a fish, bird, mammal, dinosaur or something else? In which hemisphere of the world does this species live? Does your species hibernate? Draw your fictional creature. Then explain how this creature’s characteristics might have helped it avoid extinction from the Chicxulub impact.