When a paleontologist in Montana discovered soft tissue inside a 68-million-year-old Tyrannosaurus rex bone, it upturned scientists’ understanding of how fossils decompose.
Nearly two decades later, a social media post mischaracterized the finding, saying it offers proof that dinosaurs are only thousands of years old.
In a Jan. 31 Instagram video, a man says, “According to the Bible, the Earth is only around 6,000 years old. Is there any evidence to support that?”
Another man responds by saying, “We find soft tissue in dinosaur bones showing that they cannot be millions of years old, including the presence of carbon-14 in dinosaur bones. Once again, consistent with an age of only a few thousand years.”
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Although the discovery of soft tissue in dinosaur fossils has spurred more research into what causes such tissue to be preserved, the assertion that this discovery undermines what scientists know about how long-ago dinosaurs lived is wrong.
This video clip originated from a nearly hourlong interview published by Creation Ministries International, a nonprofit that spreads the theory of young Earth creationism, or a belief that the Earth was formed in the last 10,000 years, as told in the Bible’s creation story.
The interview features Mark Harwood, who has a doctorate in radio telescopes and who has claimed in multiple public speeches that science supports the Bible’s Book of Genesis story that Earth is a few thousand years old.
Carbon-14 is a radioactive isotope — an atom with certain characteristics — of the element carbon that decays into nitrogen over time. Scientists count the number of carbon-14 atoms remaining in organic materials such as animal and plant fossils to determine their age. Carbon-14 helps archaeologists dissect the Earth’s history, but the claim is wrong that its presence in an artifact nullifies findings that show dinosaurs are millions of years old.
In 2005, paleontologist Mary Schweitzer was the first to discover soft tissues in a 68-million-year-old T. rex leg bone. It surprised scientists because soft tissue cells are known to decay more rapidly than hard tissue, such as bones and teeth. Soft tissues are believed to fully degrade within 4 million years.
Carbon-14 can date materials only back to about 50,000 years. This is because carbon-14 has a half life of 5,730 years, meaning that 5,730 years after an organism dies, half of its carbon-14 atoms turn into nitrogen atoms.
Schweitzer rejected the claim that the soft tissues found in T. rex bones mean that the fossils are only thousands of years old.
“Soft tissues in dinosaurs simply means that we don’t understand degradation at the molecular level,” she said. When dating dinosaur bones, Schweitzer told PolitiFact, paleontologists rely on several methods, including relative dating and radioactive dating.
Radioactive dating requires scientists to study radioactive elements in layers of the igneous rocks that the fossils are buried between. Geologists use instruments to determine how long it took the atoms in that material to decay and, through that process, can date the remains.
In relative dating, scientists compare fossils with other objects, such as rocks, found at a particular site.
Using these methods, scientists have found that dinosaurs roamed the Earth from about 66 million to 245 million years ago.
Since Schweitzer’s discovery, even more scientists have found soft tissues in dinosaur fossil bones. Schweitzer said there is no scientific consensus on how long it takes for soft tissue to decompose.
Many factors affect the decomposition rate, including how quickly the dead animal became buried, the environment in which it was buried, the amount of oxygen in the atmosphere, how quickly the surrounding sediments cemented and how much exposure the fossil had to bacteria or fungi.
Science around that preserved soft tissue is emerging and scientists disagree on how different factors may affect decomposition. For example, paleontologists were led to believe that low-oxygen environments might promote preservation because most fossil beds were preserved in an environment without oxygen. But a 2018 Yale University-led study found that soft tissues preserved in environments with higher oxygen levels, such as in sandstones and shallow marine limestones, resisted decomposition.
Another 2014 study that Schweitzer led hypothesized that iron particles bind to proteins in the tissue, keeping the fossils preserved longer.
A study of Montana’s Hell Creek Formation, where the T. rex bone with soft tissue was found, shows that geologists used several methods of studying the rocks in Hell Creek Formation to determine that the rocks and bones found there are approximately 68 million years old.
“They twist your words and they manipulate your data,” Schweitzer told Smithsonian magazine about young-earth creationists who have used her data to claim that dinosaurs did not live millions of years ago.
In a 2020 article published in The American Biology Teacher, a peer-reviewed professional journal for biology teachers, Fayetteville State University biologist Philip Senter said carbon-14’s presence in dinosaur bones does not reveal the bones’ age because fossils can gain more carbon-14 over time through recrystallization, bacterial activity and uranium decay.
Senter told PolitiFact that some anti-evolution authors use carbon-14 dating on dinosaur bones and arrive at false fossil ages showing them to be less than 50,000 years old.
We rate the claim that the presence of soft tissue and carbon-14 in dinosaur bones proves that dinosaurs are only a few thousand years old False.