Should Dinosaurs Be "Cloned" From Ancient DNA? PART II

As soon as the debriefing session is over, you and your teammates race over to the library that has been assembled for the benefit of the specialists and judges. Your mind is already beginning to imagine what it would be like to see a living, breathing dinosaur. Awesome! How would this be possible? What would it take to resurrect dinosaurs from the past? Under what kinds of conditions would they be kept in captivity? What implications would this have for humans and for the dinosaurs? Would this be a good thing or a bad thing?

You begin looking through the articles, books, folders, and websites. You quickly realize that: (1.) controversies persist about the existence of dino DNA during a period of rapid development of new cloning techniques and (2.) bringing dinosaurs back to life is not as simple as it seems. First of all, there are questions about whether dinosaur DNA is preserved well enough to genetically engineer a dinosaur, and then there are concerns about whether "cloning" can be achieved technologically using fossilized DNA from animals extinct for millions of years. If cloning can produce a dinosaur embryo, what are the challenges in raising, feeding, and sustaining an adult dinosaur? Is anyone thinking about safety and bioethical issues? You use your notes to create an outline of the stages that would be involved in recreating a dinosaur. It looks something like this:

Phase I -- The DNA Hunters
Phase II -- Hello, Dolly!
Phase III -- Bringing up Baby
Phase IV -- Dinosaur Husbandry I: Habits and Habitats
Phase V -- Dinosaur Husbandry II: Care and Condition
Phase VI -- Safety, Ethics & Animal Rights

You're still a little confused about how cloning takes place so you refer to the cloning video on reserve and to diagrams in the cloning e-folder that help to explain general cloning procedures in mammals (In 1996, "Dolly" was the first animal, a sheep, cloned from the cells of an adult, living animal). The sketches reveal that three animals are generally involved in cloning one individual. An egg cell is donated by animal 1 but the cell's nucleus is removed (e.g., it's enucleated and so now is without its own genes). The nucleus from a body cell of animal 2 (the animal to be cloned) is transferred into the enucleated cell of animal 1, typically after jolts of electricity open the egg's pores and allow nuclear transfer to occur. Once nucleated, the genes from animal 2 direct the egg from animal 1 to grow and develop. After cell differentiation takes place, animal 1's egg cell, which now contains animal 2's DNA, is implanted into the uterus of animal 3, which gives birth to a genetically identical clone of animal 2.

Now you're getting somewhere. You compare the "recipe" above with the drawings in the cloning e-folder. You look at the simple drawings in awe. It seems to make sense, but nobody knows how this would work exactly in dinosaurs. How, you wonder, could creatures from the Earth's distant past be cloned from ancient DNA? Presumably animal 1 would be an animal closely related to dinosaurs, such as a bird or crocodile, which would donate a living cell. Animal 2 would be the dinosaur donor of the fossilized DNA, which would have been purified, concentrated or amplified, and then replicated. Animal 3 would be the surrogate mother, once again either a bird or crocodile.

You are beginning to feel a bit uneasy. Let us assume that dinosaur "cloning" is possible using fossil DNA. What would it take to raise a juvenile dinosaur to adulthood and to maintain a captive breeding program of dinosaurs? What kinds of environments and foods would be right for the dinosaurs? To what kinds of Cenozoic diseases might dinosaurs be particularly susceptible? Could dinosaurs be used to save endangered species from extinction, or would they cause species extinctions? What ethical questions are being considered about the rights of humans and of non-human species?

In ten days, you and your colleagues will have to make a decision that will affect an entire planet: whether to "clone" dinosaurs or leave them as a part of the Earth's past. What you need is information -- enough to convince an entire team of scientists, investors, veterinarians, civilians, and judges of what would be involved.


HERE'S THE SITUATION:

As stated in Part I, in ten days you will be expected to present a full report to aid the judges in their decision. As indicated in detail earlier, each member of your team will represent one interest in this decision, such as scientist, investor, etc., and will need to be prepared to support your team's decision in court. Be prepared to consult as many sources as possible to justify your decision relying on theories of evolution, cloning, etc., and using actual or imagined examples based on scientifically accurate information. Also remember that each specialist completed a course on evolution and dinosaurs in college so that a basic understanding of these topics, no matter the specialist role, is expected.

In addition to information provided in the video, you will need to know:

 

Discussion Questions

Phase I: The DNA Hunters

  • What are the sources and approximate ages of ancient DNA in the geological record?
  • What are the major problems associated with ancient DNA?
  • How common or rare is dinosaur DNA in the ancient record?

Phase II: Hello, Dolly!
  • Once fossil DNA is extracted, what steps would be required to synthesize enough DNA for cloning a dinosaur?
  • Once enough DNA is acquired, what problems or challenges would be associated with developing a dinosaur embryo?

Phase III: Bringing up Baby
  • What factors will play a role in successfully raising a dinosaur embryo (created from ancient DNA) to adulthood?

Phase IV: Dinosaur Husbandry I: Habits and Habitats
  • Under what kinds of environmental conditions would adult dinosaurs thrive?
  • How might environmental conditions vary by dinosaur species?

Phase V: Dinosaur Husbandry II: Care and Condition
  • How would the dietary needs of herbivorous dinosaurs be satisfied with post- Mesozoic food sources?
  • How would the dietary needs of carnivorous dinosaurs be satisfied with post- Mesozoic food sources?
  • What precautions might be taken to safeguard dinosaurs from deadly viruses or diseases of the Cenozoic era?
  • What kinds of care would dinosaurs require throughout their adult lives?
  • What would be required to ensure that enough genetic diversity is maintained in the dinosaurs to avoid inbreeding and to prevent a disease or virus from wiping out the entire population of clones?

Phase VI: Safety, Ethics & Animal Rights
  • What steps would need to be taken to protect the dinosaurs from humans and humans from the dinosaurs?
  • What ethical and animal rights issues are raised by dinosaur cloning?
  • In your opinion (no matter what your teammates think), do you think humans should try to recreate a living dinosaur -- why or why not?

 

Thank you and good luck! The world is waiting to hear the court's final decision.

 

Role Assignments
High Court Judges
 

Master List of Assigned Roles (Check Moodle)


Format for this exercise and some ideas used for specialists were derived in part from a "Case Study in Science" by Shoshana Tobias, SUNY/Buffalo