Cambrian Explosion: exploring the gap (Introduction)

by David Turell , Monday, June 22, 2020, 19:45 (1404 days ago) @ David Turell

With new research it is still there:

https://phys.org/news/2020-06-microfossil-spectroscopy-dates-earth-animals.html

"Molecular clock dates for the first animals to walk the Earth don't match the fossil record. Comparing the disparate DNA of two different species and extrapolating how long it would take for them to mutate from a common ancestor suggests animals existed 833-650 million years ago, but the oldest animal fossils discovered so far only date back 580 million years. One explanation is shortcomings in the fossil record—animals did exist, but the rocks and environment were not suitable for fossilization until only 580 million years ago. Now, energy dispersive X-ray spectroscopy and high-resolution infrared spectroscopy have identified the minerals in the mudstones around ancient microfossils, giving insights into their formation suggesting that the right conditions for fossilization existed long before the first animal fossils found so far began to form.

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"Animals are relatively recent developments on Earth, predated by around 3.5 to 4 billion years of microbes. "Then, just before the last 500 million years, things suddenly get big, and we get animals for the first time," says Ross Anderson, a researcher in Earth Science at the University of Oxford in the U.K. His efforts to understand these events led him to look for the fossils of microscopic organisms more than 500 million years old that predate this "Cambrian explosion" of larger life forms.

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"The results suggest the same processes preserved pre-Cambrian microbes as later larger animals. "So the fact that there are no animals in the 800-million-year-old rocks, even though they've got the same type of preservation—all you find there are bacteria or the algae analyzed—that would suggest that animals really haven't evolved at that time," says Anderson.

"In addition, the results direct efforts to find fossils of early life to tropical regions, where there is more kaolinite. It may also give pointers for signs of life further afield. Since the kaolinite preservation process applies to such a broad range of organisms, including microorganisms, it seems a promising line of enquiry in the hunt for fossilized extraterrestrial life, which like life on Earth for the first 3.5 to 4 billion years, may have been microbial, too."

comment: The gap remains, and it is a problem for Darwinists.