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Secondary eggshell units, though rarely observed in modern avian eggshells, are marked structures in non-avian dinosaur eggshells that offer valuable paleobiological insights. Despite their significance, the origins of secondary eggshell units remain understudied, leading to debates in paleontology, including the hypothesis of an abiogenic origin for these structures. Here, we demonstrate that secondary eggshell units in non-avian dinosaur eggshells are biogenic in nature, based on analyses using advanced microscopic techniques. The structural characteristics of these units suggest a formation mechanism similar to that of turtle and crocodile eggshells, with matrix fibers likely initiating their development. Furthermore, a diminishing presence of secondary eggshell units in non-avian maniraptoran dinosaurs points to the evolution of a more refined physiological process for eggshell formation in this lineage. These findings shed light on the evolutionary trajectory of eggshell biomineralization in dinosaurs and their close relatives.
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http://dx.doi.org/10.1126/sciadv.adt1879 | DOI Listing |
Ecol Evol
September 2025
Aquatic Systems Biology Unit TUM School of Life Sciences, Technical University of Munich Freising Germany.
Historically, the thick-shelled river mussel ( agg. complex) was considered a single, widespread species across Europe. However, recent phylogenetic taxonomic revisions have delineated 12 species from this complex, including (s.
View Article and Find Full Text PDFBMC Pregnancy Childbirth
August 2025
Department of Human Nutrition, University of Otago, Dunedin, 9016, New Zealand.
Background: Poor diets and micronutrient deficiencies during pregnancy and lactation are common in Indonesia, potentially affecting linear growth. National maternal programs focus predominantly on iron-folic acid (IFA) supplementation, but adherence is poor. We explored a strategy utilizing locally available micronutrient-rich foods in the form of micronutrient-enriched crackers (MEC) to improve neonatal and infant growth.
View Article and Find Full Text PDFAnimals (Basel)
July 2025
State Key Laboratory of Agricultural and Forestry Biosecurity, College of Plant Protection, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
Housekeeping and colony defense behaviors are crucial for social aphids, as they help maintain a habitable living environment and enhance their ecological adaptability. However, over the past decades, numerous studies have focused on housekeeping and colony defense behaviors in species living in primary hosts, but little attention has been given to the secondary host stage. This constrains a deeper understanding of the altruistic behavior of social aphids, as well as the ecological and evolutionary significance of such behavior.
View Article and Find Full Text PDFActa Biomater
August 2025
Department of Biomechanical Engineering, Faculty of Mechanical Engineering, Delft University of Technology, Mekelweg 2, 2628 CD Delft, the Netherlands.
Medical devices contribute to the carbon footprint generated by the healthcare sector. The development of implants and biomaterials using recycled waste materials promotes sustainable advances in tissue engineering. Additively manufactured (AM) bone-substituting biomaterials with multifunctional properties, e.
View Article and Find Full Text PDFMaterials (Basel)
June 2025
Department of Material Science and Manufacturing Technology, Faculty of Engineering, Czech University of Life Sciences Prague, Kamycka 129, Suchdol, 165 00 Prague, Czech Republic.
This paper is focused on the modification of commercial resin by using biobased fillers during stereolithography (SLA) 3D printing. This research aims to create a composite material with a matrix made of commercially available photosensitive resin modified with a filler based on secondary raw materials and materials formed as by-products in the processing of biological materials. The research determines the effect of different fillers on the tensile properties and hardness of samples printed using SLA 3D printing, and it also investigates their integrity using SEM analysis.
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