Dinosaur Descendants
Web quest
Name:___________________________________________Date:________________________Period:_____
How can scientists learn whether an extinct species of animal is related to one that is alive today? Many extinct animals have
left behind clues about themselves. Like private investigators, researchers uncover these clues, finding evidence of the
relationships between organisms that lived the past and those that live now. Researchers use fossils to examine organisms that
disappeared long ago. While fossils are rare, with each new find scientists learn a great deal, and sometimes must rethink old
theories and hypotheses.
Task:
Suppose you visit a dinosaur exhibition at a local museum. You admire the giant reptiles’ skeletons, see recreations of their
bodies, and hear what scientists believe they sounded like. You’re especially taken by the impressive Tyrannosaurus rex. You
begin to wonder...is there an animal alive today that is related to the T. rex?
Answer your question by choosing one source of evidence—the fossil record or structural evidence—and explain what it tells
you, and doesn’t tell you, about the relationship between dinosaurs and modern animals.
Step one:
Decide what kind of evidence you want to learn more about: fossils or structures.
Step two:
Use the web sites below to find examples of how evidence supports or negates a relationship between dinosaurs and modern
relatives. Make notes about the important points you find.
Step three:
Use this evidence to prepare a synopsis of your findings to answer your question. You should also consider the limitations of the
line of evidence, and how scientists deal with them. The questions you will need to answer are on the back of this page.
Fossil evidence:
While one fossil reveals structures of an ancient organism, a group of fossils can be a record of descent from dinosaurs. Think
of the evidence in this way when you write your synopsis.
Flyin' Dinosaurs
http://www.sciam.com/ article.cfm?articleID=00003F75-5EEC-1CE1-9EEC809EC588EF21& sc=I100322
This article describes an ancient animal that shares characteristics with other dinosaurs and birds.
A Four-Winged Fossil Upends Accepted Science
http://www.csmonitor.com/ 2003/ 0123/ p01s01-usgn.html
The discovery of a four-winged fossil in China reveals a previously unknown creature and forces scientists to think again about
the evolution of birds and flight.
The Proof Is in the Plumage
http://www.naturalhistorymag.com/ 0701/ 0701_feature.html
A fairly detailed discussion of a dinosaur fossil find in China and the debate over which time period it belongs to.
Predatory Dinosaurs Had Bird-like Pulmonary System
http://www.sciencedaily.com/ releases/ 2005/ 07/ 050719001803.htm
Breathe deep: A recent study describes how the lungs of a T. rex resembled those of modern birds.
Archaeopteryx Lithographica and other species that support the dinosaur-bird link
http://alumni.imsa.edu/ ~anneka/ dinosaur/ page3.html
"Sleeping Dragon" Fossil May Link Dinosaurs, Birds http://news.nationalgeographic.com/ news/ 2004/ 10/
1013_041013_sleepy_dino.html
This fossil reveals not just structure, but also similar behavior between dinosaurs and birds.
1. Which type of evidence did you choose?
2. Are there modern descendants of dinosaurs? Use the evidence you explored to make your case.
3. Has the question of whether or not birds evolved from dinosaurs been definitively answered? Explain your answer.