A warm-blooded dinosaur that laid its eggs in communal nests?

Troodon, a dinosaur very similar to modern birds, was a warm-blooded (endothermic) animal but had a reproductive system similar to that of modern reptiles.

In addition, a new study has shown that Troodon lays 4 to 6 eggs per clutch. Since a nest with up to 24 Troodon eggs was found, the scientists concluded that several female Troodon oviposited in shared nests.

An international team of scientists led by Mattia Tagliavento and Jens Fiebig at the Goethe University in Frankfurt, Germany, examined calcium carbonate in some well-preserved Troodon eggshells.

egg temperature

The researchers used a method developed by Fiebig’s group in 2019 called “double lumped isotope thermometry.” Using this method, they were able to measure the extent to which the heavier species (isotopes) of oxygen and carbon stick together in carbonate minerals. The predominance of isotopic clump formation, which depends on temperature, allowed scientists to determine the temperature at which carbonates crystallize.

By analyzing Troodon eggshells, the research team was able to determine that the eggshells were produced at 42 and 30 degrees Celsius. Mattia Tagliavento, lead author of the study, explains in a statement: “The isotopic composition of Troodon eggshells suggests that these extinct animals had a body temperature of 42°C and that they were able to bring it down to around 30°C. How birds modern. .”

The scientists then compared the isotopic composition of reptile eggshells (crocodiles, alligators, and several species of turtles) and birds birds (chicken, sparrow, wren, emu, kiwi, cassowary and ostrich) to see if Troodon was closer to birds or reptiles. They identified two different isotope patterns: Reptile eggshells have an isotopic composition that matches ambient temperature. This is consistent with the fact that these animals are cold-blooded and slowly form eggs.

birds, however, they leave a recognizable non-thermal signature in the isotopic composition, indicating that eggshell formation is very fast. Tagliavento: “We believe that such a high performance is due to the fact that birdsUnlike reptiles, they have only one ovary. Since they can only produce one egg at a time, birds They need to do it faster.”

Large nests with 24 eggs

Comparing these results with Troodon egg shells, the researchers found no typical eggshell isotopic composition. birds. Tagliavento is convinced: “This shows that Troodon formed its eggs in a manner more comparable to modern reptiles, and implies that their reproductive system still consisted of two ovaries.”

Ultimately, the researchers combined their findings with existing eggshell and body weight data, concluding that Troodon only produces 4 to 6 eggs per reproductive phase. “This observation is especially interesting because the nests Troodon they are usually large and contain up to 24 eggs,” explains Tagliavento.

“We think it’s a strong suggestion that female Troodon oviposited in communal nests, a behavior we see today among modern ostriches,” he said. (According to Europa Press)

Espacio Vital: Dr. Johan Campos, general practice urologist, oncologist at Santa Rosa Hospital, pointed out that andropause occurs when testosterone production declines with age. Similarly, the decline occurs after about 40 years of age.

Fernando Carvallo selects information and shares his vision of national and international news. subscribe to our mailing list