Cambrian explosion Genetics Intelligent Design

Cambrian Explosion may have involved new genes

Spread the love

That’s the view taken in a new paper which departs from the consensus that modification only produced the explosion:

The Cambrian explosion was a unique animal radiation ~540 million years ago that produced the full range of body plans across bilaterians. The genetic mechanisms underlying these events are unknown, leaving a fundamental question in evolutionary biology unanswered. Using large-scale comparative genomics and advanced orthology evaluation techniques, we identified 157 bilaterian-specific genes. They include the entire Nodal pathway, a key regulator of mesoderm development and left-right axis specification; components for nervous system development, including a suite of G-protein-coupled receptors that control physiology and behaviour, the Robo-Slit midline repulsion system, and the neurotrophin signalling system; a high number of zinc finger transcription factors; and novel factors that previously escaped attention. Contradicting the current view, our study reveals that genes with bilaterian origin are robustly associated with key features in extant bilaterians, suggesting a causal relationship. – Peter Heger Is a corresponding author,

Wen Zheng, Anna Rottmann, Kristen A Panfilio, Thomas Wiehe, The genetic factors of bilaterian evolution, eLife 2020;9:e45530 DOI: 10.7554/eLife.45530

That’s pretty straightforward: “The genetic mechanisms underlying these events are unknown, leaving a fundamental question in evolutionary biology unanswered.” and “Contradicting the current view, our study reveals that genes with bilaterian origin are robustly associated with key features in extant bilaterians, suggesting a causal relationship.” = the genes originated with the bilaterians (creatures with two distinct sides).

Now here’s a question: What is the origin of new genes? We know how new ideas come into the world: People think them up. But how do new genes come into the world?

3 Replies to “Cambrian Explosion may have involved new genes

  1. 1
    polistra says:

    Seems to be an unstated assumption about the preservation of fossils. We’ve always known that only certain types of structures get fossilized. If the ‘bilaterian’ animals weren’t making calcium shells before the Explosion, we wouldn’t have them in the record. The Explosion could have been an epigenetic switchon of the shell-making genes among bilaterians. Switches are generally caused by environmental changes.

  2. 2
    doubter says:

    Polistra,

    You forget that there have been a number of Burgess Shale-type beds discovered from the Pre-Cambrian (many before the Ediacaran). Despite their ability known from the fossiliferous Cambrian shale beds to preserve soft-bodied fossils, not one of them has contained fossils at all, or at most some of the anomalous Ediacaran organisms which have little or no relationship to stem group bilateran animals.

    If this “explanation” for the total absence of precursors to the Cambrian animals in pre-Cambrian beds (despite 150 years of desperate digging) had any validity at all, then the Darwinists would have used it from the start to eradicate the notion of the mysterious “Cambrian Explosion”.

  3. 3
    polistra says:

    You’re right. I forgot about them, as well as the ‘tracks’ of soft-bodied animals that have proved to be good clues.

Leave a Reply