70 million years ago, Earth had 372 days a year, with days lasting 23 hours

PC: Wikipedia, Wilson44691 – Own work, Public Domain About 70 million years ago, during the late Cretaceous period, a year lasted roughly 372 days rather than 365, meaning each day was around half an hour shorter than it is today. The research team examined the growth layers of a single fossilised rudist bivalve, Torreites sanchezi, recovered from the Al-Hajar Mountains in Oman. Using laser-based sampling, the researchers counted daily growth increments in the shell with far greater accuracy than earlier microscope-based methods, calculating both the length of the Cretaceous day and the distance between the Earth and the Moon at the time. According to the study published in Advancing Earth and Space Sciences, titled ‘Subdaily-Scale Chemical Variability in a Torreites Sanchezi Rudist Shell: Implications for Rudist Paleobiology and the Cretaceous Day-Night Cycle’, the shell also preserved evidence of ocean temperatures several degrees warmer than today, and of a likely relationship between the mollusc and photosynthetic symbionts, similar to those in modern giant clams. Laser analysis reveals 372 daily growth rings in ancient shellThe specimen analysed in the study lived for more tha...