Dinosaur eggs have been discovered in Japan, lending new learnings about prehistoric doings in Asia. While dino eggs have been found elsewhere in the past, as early as in 1859 and 1923, they are rare in Japan, as researchers from the University of Calgary, the University of Hyogo, Museum of Nature and Human Activities, Hyogo, and Alberta's Royal Tyrrell Museum of Palaeontology said recently in the Cretaceous Research journal.
What's more, the 90 fossil eggshell fragments found in Japan's Hyogo prefecture have revealed something interesting: Five different types of dinosaurs lived in the Kamitaki region near Tamba City some 110 million years ago, during the early Cretaceous period, says Kohei Tanaka, a doctoral student in the Faculty of Science at the University of Calgary, according to a release.
The shells belonged to a variety of dinosaurs, including meat-eaters (predecessors of birds) and plant-eaters, as the scientists say in the journal.
Why Dinosaur Eggs Are Rare in Japan
This is partly because eggs are eggs, and dinosaur eggs can crack and break and crumble. But also, "It is difficult to find fossil eggshell fragments in Japan because the rock is so hard and needs to be broken apart manually, whereas in Alberta, the sediment is generally soft and can be screened for pieces of eggshell," explains Zelentisky, Tanaka's PhD supervisor and professor of geoscience, in the university release.
Volcanic and underground geological activities have compressed the rock layers, making fossils harder to find. Also, many rocks remain hidden under Japan's vegetation-covered landscape, the release said.
The Kamitaki site fossils point to new questions and possibilities for paleontological exploration in Asia. "This discovery will make people look more closely for eggshells," says Zelenitsky. "They'd be easy to miss because they're so small. They could exist at other sites, but maybe people didn't see them or recognize them." Adds Tanaka, "The quality of the specimens is very good. We're hoping to find more dinosaur eggshells or complete eggs and nests [at that site] in the future."