October 12, 2012

NEWS: Cambrian Explosion Just Got Bigger

According to new research, during the Early Cambrian—a time when many of the animal phyla were first appearing over a relatively short geological timescale—complex brains had already evolved. Instead of increasing in complexity, the brain structure of insects and their ancestors were apparently devolving a tad from more complex to less complex:

“Have spiders gotten dumber over time? That's one possible conclusion from 50 well-preserved fossils excavated from 520-million-year-old rocks in southwestern China. The fossils belong to a 6-centimeter-long early arthropod—a group that includes insects; spiders; scorpions; and crustaceans such as shrimp, crabs, and lobsters—which had a surprisingly modern brain.  . . . [E]ye stalks were preserved in many different positions—a sign that they were flexible and that the creatures could control their movement, the researchers report online today in Nature. Furthermore, they say, the appearance of such a complex brain early in arthropod evolution suggests that the nervous systems of modern-day arthropods with simpler brains—such as spiders, scorpions, and the crustaceans known as water fleas—were at some point downsized by evolution [sic.], a contrast with previous notions that the brains of arthropods in those lineages had remained simple since arthropods first arose.”
http://news.sciencemag.org/sciencenow/2012/10/scienceshot-spider-ancestor-had-.html (Emphasis added)

Now, let’s get a reminder of the complexity that arose during the Cambrian:
  • Compound eye structures with 1000’s of lenses (~515 Ma) [1]
  • Nervous systems with complex brains (little changed since that time, over 520 million years)
  • 11 to 23+ animal phyla of 32 (phyla are basic body types), and perhaps many more extinct phyla
  • Diverse complex cell-types
How many eons would it take for accidental changes in DNA to stumble upon all the complexity? Certainly, it would take longer than a meager 20 to 100 million years. Consider also that the compound eyes and complex brain structures have changed little after 500 million years. How does that make sense in terms of random, mindless evolution? Complexity arose in under 100 million years, and then there were 500 million years of relative stasis—preservation of complexity but little or no improvement. This does not sound like the work of chance to me.

It is worth mentioning that we are no closer to finding the necessary intermediate forms that would be expected and required of undesigned evolution. With undesigned evolution there must be many small steps of improvement that lead to complex designs, like the brain structure mentioned above. So far the fossil record keeps disputing Darwinian evolution. It is not enough that there are species of animals with varying degrees of complexity of eyes or brains. Darwinian evolution demands that complex structures evolved slowly from preexisting simple structures. The fossil record does not show this predicted gradual increase in complexity. This should make typical evolutionists nervous—very nervous. (That intricate brains would quickly evolve fits my model and predictions, as mentioned in a previous blog post [2], under points (4) and (16).)

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