As we all know, the growth of any creature on Earth is constrained by environmental factors. In the long years, when the earth revolves around the sun, it produces: the change of seasons, the ebb and flow of the tide; These changes have a cyclical impact on the growth of organisms' hard bodies, bones, etc.
These effects are generally reflected in the hard body part of the organism. Scientists believe that organisms behave in terms of growth rhythms to represent changes in this cycle. Therefore, the fossils preserved by these creatures are the best ancient calendars, also known as paleontological clocks.
Paleontologists, after studying the growth rhythms of fossils from various geological epochs, especially corals, bivalves, cephalopods, floating feet and stacked layers, were surprised to find that these fossils can provide a lot of valuable information for geophysics and astronomical research.
The skeletons of many organisms show obvious cycles such as years, months, and days. During the growth process, reef-building corals can secrete calcium through zooxanthellae in the body. As calcium increases, bones continue to pile up.
Through observation, Irene, a British paleontologist, found that the accumulation rate of reef-building corals shows the characteristics of fast during the day and slow at night. Moreover, every passing day, the coral will form a thin growth pattern.
And, Irene found that as the seasons change, the growth rate will also be affected. The calcium accumulation of corals will change periodically and density with the change of seasons.
This change, in fossils, is manifested as a growth ring (similar to the rings of trees). Each growth ring, representing a year; The growth patterns and growth rings of coral fossils can be said to record the changes in historical years.
American paleontologist Wells research showed that 380 million years ago, on a coral in the Ordovician-Devonian era, the growth ring contained 400 growth stripes. This suggests that in the Devonian, the time of year should have been 400 days. At the same time, he cites data on the growth of corals from the Paleozoic Era.
450 million years ago, there were 412 growth rings; 330 million years ago, 398 growth rings; 300 million years ago, there were 390 growth rings. These enumerated data show that the newer the geological epoch, the fewer growth links and the fewer dates of the year. In this way, the law of gradually slowing down the rotation rate of the earth in geological history is confirmed from the side.
According to astronomers' calculations:
1. In the Cambrian era, the daily length was 20.7 hours;
2. In the Devonian era, the daily duration was 21.5 hours;
3. In the Carboniferous Period, the daily duration was 21.9 hours;
4. In the Triassic era, the daily duration was 22.5 hours;
5. In the Cretaceous era, the daily duration was 23.5 hours;
Until the Quaternary, which is now, we had spent nearly 24 hours a day.
Scientists analyzed the data and found that the number of days a year in the Devonian and Carboniferous periods was much more than now. At the same time, according to the study of fossil growth lines, the Earth's rotation cycle slows down and is uneven.
From the Carboniferous to the Cretaceous, the slowdown rate was very small, while at the end of the Cretaceous period, the speed increased significantly. These research results coincide with the astronomers' estimated conclusions! This further shows that fossils can be said to be ancient calendars, recording a series of changes that occurred at that time!
Of course, many marine life is physiologically inextricably linked to the moon's movements or tidal cycles! Finally, if you have any views, welcome to leave a message in the comment area!