An international team analyzed the genetic material decay rate of DNA extracted from an extinct MOA skeleton fossil and found that although the short DNA fragment may exist for 1 million years, the half-life of 30 or more base pair sequences under certain conditions is only about 158000 years
The fossil samples studied above may be contaminated by human DNA
 According to this, a scientist believes that reconstructing dinosaurs with ancient DNA is similar to the story of the film Jurassic Park is impossible to happen