The Signal

Serving the College since 1885

Sunday May 26th

Dinosaurs Still Walk Among Us, But Most Fly

<p>In recent years, experts have been doing more research to deepen the link between birds and dinosaurs (Photo courtesy of Mark Witton and Darren Naish, <a href="https://creativecommons.org/licenses/by/3.0" target="_blank">CC BY 3.0</a>, via <a href="https://commons.wikimedia.org/wiki/File:Life_restoration_of_a_group_of_giant_azhdarchids,_Quetzalcoatlus_northropi,_foraging_on_a_Cretaceous_fern_prairie.png" target="_blank">Wikimedia Commons</a>).</p>

In recent years, experts have been doing more research to deepen the link between birds and dinosaurs (Photo courtesy of Mark Witton and Darren Naish, CC BY 3.0, via Wikimedia Commons).

By Amber Nodes
Staff Writer

While “Jurassic Park” is a wildly popular cultural phenomenon, the movie spread misinformation, myths and “maybes” about the existence of dinosaurs. In 1993, it showcased cold and unfeeling lizard-like monsters who are scaly, skinny and scary.

This stands in stark contrast to the living, modern-day dinosaurs: birds.

“While Jurassic Park is one of my favorite movies, it's based largely on science fiction and perpetuates negative stereotypes of dinosaurs as bloodthirsty predators. The movies miss the mark when it comes to conveying the richness of dinosaur lives,” said Dr. Seth Coleman, who completed his Ph.D. in evolutionary biology after having a lifelong obsession with nature, in a text interview. He uses his education to teach viewers about biology through his TikTok account, @chuckdarwin, which has over 76,000 followers.

Coleman and other experts agree that dinosaurs may be a favorite of many children and a staple of early-life science classes in school, but the public’s perception of dinosaurs is warped by the media and movies they have been exposed to.

“I don’t know anything about dinosaurs, but I love them,” said junior kinesiology and health sciences major Kasey Hammer.

According to OnePoll, a public relations survey company, 64 percent of adults said they were obsessed with dinosaurs as children, yet most Americans believe misconceptions and falsehoods about them. 

“Some eat [leaves] and some eat people,” said senior business major Noah Harrison with a chuckle.

A few dinosaurs survived the mass extinction event 66 million years ago. They are known as the avian dinosaurs and are flightless. They would eventually grow and change into a massive and diverse group that we now refer to as birds. All the extinct species of dinosaurs are non-avian dinosaurs, and there are no living descendants from them.

So yes, technically, most dinosaurs are extinct, but not all of them are.

How We Know Birds Are Dinosaurs

In recent years, experts have been doing more research to deepen the link between birds and dinosaurs. As shown in old articles from the Washington Post and the New York Times, this was a hot topic of debate in the paleontology community, where the evolution of birds was shrouded in a mystery of how birds eventually gained flight and lost their “reptilian” traits.

The first hint that birds were descendants of dinosaurs was the discovery of archeopteryx in 1861, just a few years after Charles Darwin published his theory of evolution.

The archeopteryx is a bird with many dinosaur traits and was widely considered the oldest bird for years — it is basically a dinosaur with feathers.

“Birds being considered dinosaurs wasn’t controversial among scientists,” said Coleman. “The challenge to this day is convincing the public of that.”

Most paleontologists were convinced of the link by the late 1900s and also convinced that archeopteryx marks the transition phase between avian dinosaurs and birds.

This direct link classifies birds as dinosaurs, specifically avian dinosaurs. It is similar to how humans came from ancient mammals, which classifies humans as a type of mammal.

What This Changes About How We Understand Dinosaurs

Birds are descended from a group of dinosaurs called the theropods, meat-eating dinosaurs. Members of this group include the well-known T-Rex, along with other smaller dinosaurs more closely related to birds, like the velociraptor.

“The evidence is overwhelming that birds are theropod dinosaurs,” said Coleman. “In addition, we should let birds inform us on possible dinosaur behaviors, especially of the theropod dinosaurs. These beautiful beasts were courting each other, displaying to rivals and many of them had feathers that they used for this. Imagine the colors!”

Theropods already held a lot of the traits that eventually would become a staple for birds—many had modified scales, also known as feathers. According to the University of California, Berkley, the feathers of archeopteryx are almost identical to the feathers of birds today.

Oviraptorosaurs were theropod dinosaurs that were highly feathered and had other traits commonly found in birds, like hollow bones and egg brooding.

“Until only recently, we assumed the oviraptor fossils we found showed them stealing eggs, when in fact they showed a parent trying to shield their eggs from danger,” said Coleman.

Why Classifying Animals Can Be Confusing

Animal classification is flawed and sometimes flat-out wrong. Scientists are hesitant to fully overhaul the system, leading to incremental change when something becomes undeniable, but leaving aspects that can be confusing.

“It’s important to recognize that we’re using human-constructed classifications. That said, using a combination of species concepts allows us to categorize life pretty effectively for our needs,” said Coleman.

Carl Linnaeus, a doctor and biologist, created the system used to classify animals by their traits which eventually became the system we still use today. The animals were named based on their genus and species names, often in Latin. The main issue with classifying animals this way is that sometimes animals that look alike are not as closely related as they seem, or animals that are closely related may not look similar at all. When DNA analysis was introduced, it led to the testing of animals and some rearrangement of evolutionary relationships based on the closeness of DNA relations.

One example of this is falcons and hawks. Both are similar in look and behavior, but falcons are more closely related to parrots and comparatively are not closely related to hawks.

Before modern science, there were five groups of animals: amphibians, birds, fish, mammals and reptiles that each have their own clade, which are evolutionary branches of animals. DNA analysis of these clades shows their relationships are not as simple as previously thought.

Mammals have a singular common ancestor, and every organism that came from the common ancestor is a mammal. That is what makes mammals a true clade.

Reptiles don’t have a singular common ancestor from which only reptiles originate. This means the definition of clade doesn’t apply to the group formerly classified as “reptilia”.

From their common ancestor, all the reptiles evolved, but so did other groups that are not considered reptiles—birds and mammals. Thus, the clade of reptiles has been abandoned by most scientific classifications. If they weren’t, birds and mammals would have to be included in the reptile clade.

“Birds aren’t reptiles,” said Hammer. “They fly.”

The picture of how scientists think dinosaurs look has changed in the past couple of decades as further understanding and more discoveries have been made. In reality, they may not have been as skinny or scaly as shown in pop culture.

When looking at the fossils of dinosaurs, human reconstructions have been biased to appear like a reptile, leading to the “shrink wrap” effect, which is an effect where dinosaurs are reconstructed to have little-to-no body fat and are featherless. This is why dinosaurs are often shown to be so tightly wrapped around their bones, instead of being animals with fat and muscle, like birds are.

While popular films like “Jurassic Park” are really based on science fiction rather than science, viewers do not fully understand how complex avian dinosaurs are and how they may be more bird-like than reptile-like. The educated guesses about extinct avian dinosaurs should be punctuated with what is known about their living relatives, birds, and the old idea of reptilian monsters should be left in the past.




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