Uncovering The Facts Behind the Discovery of Dinosaur DNA

Tom Johnson - 2019-12-16T22:00:00.000Z

Researchers from China and the United States co-published a study in the National Science Review on January 12th, 2020.

It changes many things we currently know about histological preservation.

The study proves traces of DNA-like cellular material in the remnants of a 75-million-year-old dinosaur exist.

This study marks the discovery of the first-ever sub-cellular preservation of DNA in vertebrates.

The development merits the research possibilities with fossilized animals for upcoming scientists. It also opens up the molecular secrets of the extinct species we know very little about.

Still, not all scientists are welcoming this discovery with open arms.

Explore the complete story around the ground-breaking revelation of dinosaur DNA below. Our list of three heated controversies surrounding this breakthrough busts many popular myths amongst skeptics too.

How Did Scientists Discover Dinosaur DNA?

Researchers found cellular material that looks and behaves like DNA while studying herbivore dinosaurs.

The organic material comes from nestling dinosaurs that once lived in northwestern Montana.

The following will look at the three stages of research and analysis that led to this exciting discovery.

Fossils Found In 1988

It was in 1988 that bones and skulls of dinosaurs around the Two Medicine formation were found by Jack Horner.

A Chapman University paleontologist, Jack was also the technical advisor for Jurassic Park. The team found dozens of found duck-billed dinosaur nestlings from the Mesozoic era.

The paleontology team embedded parts of the skull of Hypacrosaurus stebingeri in resin.

They also grounded the specimen into parts bigger than hair strands for research. Unfortunately, the slides were shelved for decades.

Fossils Studied In 2010

Specimen MOR 548 was reopened 22 years later by a PhD researcher from the Chinese Academy of Sciences.

Lead researcher Dr. Alida Bailleul was working at MOR when she discovered the chromosomal material. She was checking for sutures around the skulls of Hypacrosaurus at the time.

The doctor noticed circular cell-like formations around the supraoccipital bone. Upon looking closer into the calcified cartilage, she discovered dark matter resembling nuclei. This led to further tests and developments in the case.

Fossils Analyzed For Ten Years

Around the same time, North Carolina University paleontologist Mary Schweitzer visited MOR.

A former doctorate student of Horne, she went through the study as well as its results. Mary is a molecular paleontologist known for her studies on cellular preservation in dinosaur fossils.

Finding the discovery revolutionary, Mary joined forces with Bailleul and her team for the next ten years to study it further.

They analyzed the research and cross-checked the results before recently publishing their findings recently.

Which Tests Were Conducted To Confirm Dinosaur DNA?

The international team of researchers tested samples in Raleigh, North Carolina. They compared MOR 548 with ground sections of skulls in de-fleshed juvenile emus.

The following explains the two tests used by the research team to confirm the presence of DNA markers, proteins and chromosomes.

Collagen II Test

This immunological test confirms the presence of cartilaginous proteins in dinosaur fossils.

It was concluded when MOR 548 specimens reacted to antibodies of the cartilage protein- Collagen II.

The presence of similar proteins was confirmed when the organic matrix of the aDNA reacted like the emu sample.

Chemical Stain Test

Researchers who did this study also applied two types of DNA stains to test the presence of chromosomal matter in it.

· Dye Test 1: The first test included Propidium Iodide stains on the chondrocytes of Hypacrosaurus and emu skulls.

The dinosaur specimen showed a faint red fluorescence. Similarly, the emu sample showed a strong red hue.

· Dye Test 2: The second DNA-detecting stain test is 4′,6′-diamidino-2-phenylindole dihydrochloride or DAPI.

Both the specimens showed blue fluorescence indicating the presence of DNA matter.

Understanding the Controversial Discovery of Dinosaur DNA

Skeptics are rejecting the pioneering discovery of dinosaur DNA for many reasons.

A heated controversy is about the debated study on soft tissue cells published by Mary Schweitzer.

Other arguments include contamination and the restricted scope of histological preservation.

The following discusses three controversies around the discovery of dinosaur DNA in detail.

Molecular Preservation is Limited

While the half-life of DNA is 521 years, the current study stretches it further ahead.

Another study conducted in 2014 on a 180-million-year old fern discovered nuclei and chromosomal matter. This shows our awareness of ancient DNA is expanding with advancing technology.

The Specimen Is Contaminated

Many skeptics argue that the dinosaur DNA could actually be a fossil byproduct or a bacterial biofilm.

Conversely, microbes do not react to Collagen II like genetic materials do. Furthermore, the cartilage is not porous.

The same is why it does not undergo any significant oxygen damage.

Hence, internal decay and contamination is negligible in such a specimen.

In fact, cartilage is the best part of the anatomy for preserving biomolecules in deep time.

Moreover, the biomolecule discovered from the extinct species was in a condensed state when the organism died, ensuring the bio-matter was well-preserved.

The authors also clarify that scope of cross-contamination is negligible here as the emu specimen was studied at a different lab.

Short Fragments Are Unreadable

Paleogenomicists like Beth Shapiro rebut that tiny fragments of DNA from ancient fossils are worthless for genome sequencing.

She argues that such a genetic material is not sufficient enough for accurately placing in a genome.

Jasmina Wiemann, a PhD student majoring in fossilization of biomolecules, claims otherwise.

She suggests that proteins link with the DNA-strands during fossilization.

This stabilizes the genetic material for long periods of time.

Hence, short fragments of biomolecules are capable of preserving important DNA information.

This could include knowledge about metabolism or growth of the organism, unbeknownst to the world.

Conclusion

If the discovery of dinosaur DNA is eventually proven right it will likely push other scientists to explore more about fossil DNA in the near future, giving us more valuable answers about dinosaurs.