Low diversity may have led to dinosaur extinction

The result was published in the academic journal PNAS on Tuesday.

"To solve the mystery of dinosaur extinction, it's key to study the record of their existence on the earth in terms of space and time," said Han Fei of China University of Geosciences (Wuhan), the lead author of the paper. Han added that eggs not only reflect dinosaur reproduction but also give information about environment they lived in.

Incubation of eggs depends on proper temperature, humidity and concentrations of carbon dioxide. The research said that in the Late Cretaceous period, with a changing natural ecology, dinosaur biodiversity saw a continuous reduction, which weakened their ability to adapt to the environment and made it impossible for them to survive a major disaster, such as an asteroid collision or volcanic eruption. All elements combined led to their extinction.

The trend of reduced diversity was also found in fossils in other areas such as Laiyang, Shandong province, and Nanxiong, Guangdong province, the researchers said.

The research was co-produced by the university, the Institute of Vertebrate Paleontology and Paleoanthropology and the Institute of Geology and Geophysics of the Chinese Academy of Sciences.