Can the gender of dinosaur fossils be determined?

Is it possible to determine the sex of dinosaur skeletons as scientists often do?

The truth about the lives of prehistoric dinosaurs always attracted the attention of many people. If you have ever been a fan of movies like: Jurassic Park, Dinosaur or Night in the museum . surely can not forget the image of the giant dinosaurs with the power of seemingly nothing to stop .

Now, though, the giant dinosaurs are extinct, but they still leave evidence and traces that scientists can learn more about life on Earth hundreds of millions of years ago. Field Museum in Chicago is home to the world's most complete tyrant dinosaur skeleton. With an impressive height: almost 4 meters and the length of this dinosaur is 12.8 meters. Experiencing many fluctuations of time, many fossil dinosaurs are lost or bones are broken, but Sue - the name given to the dinosaur by the scientists, remains intact for more than 90%.

They conducted the construction and assembly of each of its bones to form a complete model, bringing the most authentic feel to visitors at the Field Museum. It is known that the Sue dinosaur is currently about 67 million years old.

The Sue tyrant dinosaur is on display at the Field Museum, Chicago.(Photo: spintech7.cnsi.ucsb.edu)

Paleontologist Sue Hendrickson discovered this skeleton in southern Dakota on August 12, 1990. Since then, scientists have discovered many things about Sue's life. Although some ribs were broken, the dinosaur lived for a long time compared to the age of a common tyrant dinosaur. This is clearly shown on the skeleton shell, and researchers also estimate that Sue weighs about 7 tons, equivalent to an African male elephant. But the only difficulty for scientists is that they still don't know how to distinguish the sex of this dinosaur. This is particularly important, because gender greatly influences the behavior of all living things, and it is clear that a male or female dinosaur will help them learn more about their life.

For all species that use sexual reproduction, finding their gender is quite easy. You only need to look at external behaviors or expressions or simply look at their genitalia. However, finding out the true gender of a dinosaur is quite difficult because there are no longer any dinosaurs to observe. The genitalia is made up of soft tissues that cannot be fossilized. In addition, archaeologists believe that dinosaurs, like birds, use acupoints to reproduce and release solid and liquid waste. So even if the researchers found a dinosaur fossil with a well-preserved skin, they still didn't know the dinosaur's true gender with certainty.

Even studying DNA is not very helpful for dinosaurs. For mammals, we often distinguish males and females from their X and Y chromosomes but reptiles often do not follow this rule. In some reptiles, the temperature of the egg determines the sex, not the chromosome. In addition, DNA will be broken during the fossil process, so very few researchers use this method of analysis.

A male ostrich is brooding

But that doesn't mean it's impossible to find out the true gender of a dinosaur. In 2005, in Jiangxi Province, China, archaeologists discovered a skeleton with eggs inside - a very clear indication that this is a female skeleton. However, overturning the problem, eggs are not always the most reliable evidence. For some dinosaurs, like ostriches or emu birds, the males are also the ones that will hatch the eggs.

Another way to differentiate sex is through studying heterosexual malformations . Similar to peacocks, they possess large, colorful tails, the main purpose of which is to attract other females. It is possible that the differences in valances in the neck or crest on the top of the head will help male dinosaurs be used to attract mates. Body size and ratio may also be related to the sex of a dinosaur. Archaeologist Phil Senter hypothesized that long necks of long-necked dinosaurs such as Diplodocus or Apatosaurus could be evolved through sex delineation, longer necks would attract females. easier.

However, when making these assumptions, the researchers still do not know for sure which of the females are females, although it is clear that the differences made by sex. Will a Triceratop triceratism use frills around his neck to attract a mate or to do something else? In fact, if you have not seen the genitalia of a dinosaur, it is very difficult to be certain.

Besides finding dinosaur fossils filled with an egg nest inside, scientists found another way to identify a female dinosaur if at that time they were pregnant. In 2005, Dr. Mary Schweitzer and Jennifer Wittmeyer and John R.Horner reported on the discovery of bone marrow in a fossil of T-rex in Science magazine. For females, bone marrow is located inside the bone or in the cavity. They use this type of bone to provide the calcium needed to make eggshells. Similarly, the dinosaur that researchers are investigating has been identified as a female and pregnant. Unfortunately, archaeologists can only determine the sex of a dinosaur with certainty through this method of bone marrow analysis. And the prerequisite is that they must be pregnant.

With groundbreaking findings like that of Dr. Schweitzer and a large number of fossils being excavated in places like China and the United States ., maybe one day, the true gender judgment of a dinosaur will be a lot easier. It will help a lot of scientists, revealing the mysteries of the ancient 'civilization' of dinosaurs. However, for now, the true gender of a dinosaur is still a mystery.