The 'earliest known example' (520mya) discussed dates to around the cambrian explosion, the geological period where the fossil record is rich with "earliest examples" and type specimens for phylums.
Maybe another way to put it is 'The definition of brain used in this article might apply to organs other than the brain in modern species." It's basically a nervous system, centralized or not. Who knows what it did or what it was for. It may have a predecessor outside the animal kingdom. Plants have sensory perception, or some version of it.
I'm not disputing the claims in this article or anything else. I'm basically agreeing with you.
Whether or not some nervous system, nerve cells or complexes of nerves evolved 520+mya and were 'lost' in some phyla or was evolved through convergent evolution a little later, it's partially a semantic issue: do we call something a brain. Most of what makes a brain a brain probably came later and evolved separately in different phyla. This means radically different ways of doing things.
BTW, Richard Dawkins really turned me on to evolutionary biology (a side gig, when he's not arguing with dummies) in some of his books. "Ancestors Tale" is awesome for really getting the "phylogenetics" way of thinking discussed here.
Maybe another way to put it is 'The definition of brain used in this article might apply to organs other than the brain in modern species." It's basically a nervous system, centralized or not. Who knows what it did or what it was for. It may have a predecessor outside the animal kingdom. Plants have sensory perception, or some version of it.
I'm not disputing the claims in this article or anything else. I'm basically agreeing with you.
Whether or not some nervous system, nerve cells or complexes of nerves evolved 520+mya and were 'lost' in some phyla or was evolved through convergent evolution a little later, it's partially a semantic issue: do we call something a brain. Most of what makes a brain a brain probably came later and evolved separately in different phyla. This means radically different ways of doing things.
BTW, Richard Dawkins really turned me on to evolutionary biology (a side gig, when he's not arguing with dummies) in some of his books. "Ancestors Tale" is awesome for really getting the "phylogenetics" way of thinking discussed here.