{"id":672657,"date":"2025-05-30T23:14:59","date_gmt":"2025-05-30T20:14:59","guid":{"rendered":"https:\/\/en.buradabiliyorum.com\/dinosaur-eggshell-study-confirms-biogenic-origin-of-secondary-eggshell-units\/"},"modified":"2025-05-30T23:14:59","modified_gmt":"2025-05-30T20:14:59","slug":"dinosaur-eggshell-study-confirms-biogenic-origin-of-secondary-eggshell-units","status":"publish","type":"post","link":"https:\/\/buradabiliyorum.com\/en\/dinosaur-eggshell-study-confirms-biogenic-origin-of-secondary-eggshell-units\/","title":{"rendered":"Dinosaur eggshell study confirms biogenic origin of secondary eggshell units"},"content":{"rendered":"
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\n The differences between the biogenic and abiogenic calcite in dinosaur eggshells. Credit: IVPP
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The calcitic layers of the eggshells of archosaurs (including crocodilians and birds) and turtles are composed of distinctive crystalline structures known as eggshell units. Those growing from the shell membrane are called primary eggshell units (PEUs), while those forming within the calcitic layer are called secondary eggshell units (SEUs). Although rare in modern bird eggs, SEUs are common in dinosaur eggs. Due to the lack of in-depth research on this structure, however, scientists are uncertain whether they are biogenic or abiogenic in origin.<\/p>\n

To tackle this issue, an international research team led by Dr. Zhang Shukang and postdoctoral researcher Dr. Choi Seung from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Science<\/a>s, has conducted a comprehensive study of SEUs in dinosaur eggshells using techniques including electron backscatter diffraction (EBSD), polarized light microscopy (PLM), and scanning electron microscopy (SEM). For comparison, they examined some eggshells of modern birds, turtles, and crocodiles.<\/p>\n

The study revealed that the crystallographic characteristics of dinosaur egg SEUs were almost identical to those of PEUs. Notably, they also matched the crystallographic characteristics of the SEUs in modern turtle and crocodile eggshells.<\/p>\n

Additionally, the SEUs in dinosaur eggs exhibited numerous grooves and vesicles, similar to those in modern bird eggshell units. These grooves and vesicles were interpreted as remnants of spaces left by the degradation of organic matrix fibers during fossilization. These findings<\/a>, published in the journal Science Advances<\/i>, strongly suggest that the SEUs in dinosaur eggs are biogenic structures.<\/p>\n