origin of humans; evolution of the skull (Origins)

by David Turell @, Thursday, October 12, 2023, 18:08 (192 days ago) @ David Turell

Started with a fish 450 million year ago:


"This 455-million-year-old specimen of Eriptychius americanus contains the earliest ever seen neurocranium — the cartilage protecting the fish’s brain — and one of the strangest. According to the study, the fish’s cartilage fits neatly yet loosely around the brain in a design with no known analogue.

"As the earliest vertebrate neurocranium ever studied, it fills a 100-year gap between the earliest such fossils ever recovered previously (from about 400 million years ago) and the origin of vertebrate fish some 500 million years ago.

"One of the greatest innovations of the vertebrate body plan, the neurocranium both protects the brain and helps to connect it to sensory organs, the mouth and more. In humans, the neurocranium is the portion of the skull that contains the brain, and the skull's seam-like sutures allow it to expand all the way until early adulthood to allow for growth.

"While the human skull is composed of 22 different bony pieces, E. americanus’ neurocranium was composed of 10 long pieces of cartilage that fit together without being fused, according to the X-ray scans. The imaging also revealed that canals snaked through the cartilage to deliver either blood supply or connections to sensory organs. The fish’s skin wrapped tightly around the whole structure, though the scientists noted a clear anatomical distinction between the two.

"This novel neurocranium falls somewhere between the loose, open cartilage style seen with lampreys and the more closed-off designs present in gnathosomes, a group that includes humans.

"Vertebrates exist with both structures, and scientists have tried to determine how they evolved. The new paper speculates that the largely locked-up cranium we enjoy evolved later down the line from E. americanus.

"Ultimately, that layout became a central part of gnathosomes as we know them (and us) today.

“'These are tremendously exciting results that may reveal the early evolutionary history of how primitive vertebrates protected their brains,” said Ivan Sansom, a paleobiologist."

Comment: the brain is so important it must have a protective casing. How did an unguided evolution have the foresight to recognize the potential dangers to a soft brain? This shows the purposeful design a designer would follow. When studying evolution, it is always important to ask why and how this new event happened. Look for purpose and you will see design.

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