Will We Clone A Dinosaur?

The short answer is no. The slightly longer answer is definitely not. The Jurassic Park idea--amber, insects and bits of frog DNA--would not work in a million years, and it was by far the most ingenious suggestion yet made for how to find dinosaur genes. Cloning a mammoth--flash-frozen for several thousand years--might just prove feasible one day. But dinosaurs, 65 million years old? No way.

It is only when you ask the question the third time that you begin to see a glimpse of an affirmative answer. Start with three premises. First, dinosaurs did not die out; indeed there are roughly twice as many species of their descendants still here on Earth as there are mammals, but we call them birds. Second, DNA is turning out to be a great deal more "conserved" than anybody ever imagined. So-called Hox genes, which lay down the body plan in an embryo, are so similar in people and fruit flies that they can be used interchangeably, yet the last common ancestor of people and fruit flies lived about 600 million years ago.

Third, and most exciting, geneticists are finding many "pseudogenes" in human and animal DNA--copies of old, discarded genes. It's a bit like finding the manual for a typewriter bound into the back of the manual for your latest word-processing software. There may be a lot of interesting obsolete instructions hidden in our genes.

Put these three premises together, and the implication is clear: the dino genes are still out there. So throw your mind forward a few decades, and try out the following screenplay. A bunch of bioinformatics nerds in Silicon Valley, looking for an eye-catching project to showcase the latest IPO, decide to try to re-create the genome of a dinosaur. They bring together a few complete bird genomes--complete DNA texts from the cells of different birds--and start mapping the shared features. The result is a sort of prototype genome for a basic bird.

Then they start fiddling with it--turning on old pseudogenes; knocking out the genes for feathers and putting back in the genes for scaly skin; tweaking the genes for the skull so that teeth appear instead of a beak; shrinking the wings, keel and wishbone (ostrich genes would be helpful here); massively increasing size and sturdiness of the body; and so on. Pretty soon they have the recipe for a big, featherless, wingless, toothy-jawed monster that looks a little like a cross between a dodo and a tiger.

They might not have to fix that many genes--just a few hundred mainly developmental ones. The genes for the immune system, for memory mechanisms and the like would all be standard for a vertebrate. To fine-tune the creature, they could go fishing in other bird genomes, or perhaps import a few ideas from lizards and turtles.