To accompany feature “Dinosaur-killing asteroid radically changed Earth’s tropical forests”

SCIENCE

Before Reading:

1.  What is a forest and what factors can affect which plants and other species live in a forest?

2.  An asteroid is largely credited with killing off the dinosaurs. How do you think an asteroid impact might have done that? How might plant species across the globe have been affected by that asteroid impact?

During Reading:

1.  When did the asteroid impact occur? It’s credited with triggering an extinction event. What is that?

2.  What happened to tropical forests as a result of the asteroid impact?

3.  What types of fossils did the researchers use to assess what the ancient forests were like before and after the asteroid impact?

4.  How much did the impact affect plant diversity — and for how long?

5.  What type of plants came to dominate after the asteroid impact? How did this mix differ from what had been typical in tropical forests earlier?

6.  What three post-asteroid changes does the story suggest helped reshape the tropical forests?

7.  How did insects change with the new forest structure? What evidence do scientists have for that? What type of insects does Conrad Labandeira say were most likely to survive? Which class of insects got “creamed”?

After Reading:

1.  This story focuses on abrupt changes to forest ecosystems long, long ago. The natural recovery from those changes took a long time. Do you think the new data offer any lessons about the potential long-term effects of changes occurring on Earth today? Explain your answer.