Talk:Spriggina

Latest comment: 2 years ago by Donald Albury in topic To fuse or not to fuse...

In one speculative view, a spriggina would wriggle up onto a stationary frond-like, mushroom-like or plant-like lifeform, release digestive juices, let the juices loosen up the victim's flesh, and them absorb it internally.

It may actually be the mouth that was the Cambrian-explosion-triggering device, not eyesight, as is commonly speculated. A mouth allows one to eat on the run. This could explain why the precambrian critters mostly dissappeared: they were overly adapted to external digestion such that they couldn't get away from preditors and digest food at the same time.—Preceding unsigned comment added by 68.183.137.111 (talkcontribs)

Cite reliable sources for this speculation, and it can be used. -- Donald Albury 11:49, 13 December 2006 (UTC)Reply

According to Stephen C Meyer it actually exhibits glide, not bilateral, symmetry. Also according to Rodin, Szathmary and Rodin in, “on the origin of the genetic code and tRNA before translation” — Preceding unsigned comment added by 2607:FE28:207F:8700:C8F:33CF:E9DF:3A8B (talk) 22:31, 1 June 2018 (UTC)Reply

Material by User:Philcha moved from Cambrian explosion

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The following could use incorporation here. Smith609 Talk 20:42, 9 June 2008 (UTC)Reply

but its body segments seem to be offset across the midline rather than being symmetrically paired as as they are in all known arthropods;[1]

  Done08:01, 10 June 2008 (UTC)

References

  1. ^ Ivantsov, A.Y. 2001. "Vendia and other Precambrian "arthropods"". Paleontological Journal. 35: 335–343.{{cite journal}}: CS1 maint: numeric names: authors list (link)

To fuse or not to fuse...

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"its front few segments fused to form a head" (Introduction) would seem to contradict "The organism was segmented, with no fused segments" (Morphology).Tapatio (talk) 07:09, 12 July 2012 (UTC)Reply

Whether Spriggina has "differentiated parts" is controversial. Some reconstructions show a distinct "plow" for a head. But the fossils seem to show a more ambiguous transition from the body to the plow portion, suggesting the plow is just a thicker "segment". It's unclear what's actually going on at the "head". It matters in debates about whether Spriggina may be a single cell, or possibly a single multi-nucleus cell, as found in some existing large-cell life-forms. One interpretation is that the fact it has "trouble" forming a clear head structure is evidence of being single-celled. Another is that because the most frontal plow segment may break off, the segments just behind it are "getting ready" to be a plow by gradually thickening up, creating a kind of twisted look seen in some fossils. In this interpretation, a given segment has to grow wider to cover both left and right to serve as a proper plow. Those segments just behind the final plow are thus in mixed stages of widening/thickening, some covering say 2/3 of the width, giving the "mid head" the asymmetrical appearance seen in many fossils. This interpretation doesn't directly depend on a particular cell structure model, but may imply that each segment is a cell in itself. --146.233.0.202 (talk) 16:45, 28 February 2022 (UTC)Reply

Are you proposing a change to the article? If so, please provide reliable sources to support such changes. - Donald Albury 17:54, 28 February 2022 (UTC)Reply

strange "may have"

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Just a question to those who have access to the sources: it's interesting, is there any fossil evidence for speculations like "may have been predatory", "may have borne eyes and antennae"? And about the head - I agree with Tapatio, it doesn't seem that the way of head forming is known. Stas000D (talk) 11:25, 20 August 2012 (UTC)Reply