Tubes on Mars
What about this?
What is the shiny knoblike structure on the tube?
Could it also have something to do with an animal or plant life form?
Crinoid stem and bottom of calyx?
This fossil appears to be a crinoid stem and the bottom part of the calyx.
I am not certain. It could be one of the crinoid species, or it could be a different
kind of echinoderm, or even a plant.
light and shadow tricks. The calyx (if that is what it is) - the knob in the image - looks flat on top.
In reality it is pointed. Or rather, the part that looks flat in the image is
actually slanted on the fossil, and slightly concave. This is probably where the stem
connected to it.
Changing this image to grayscale and inverting it almost makes it look correct.
One can see the indentions in the calyx bottom but other things don't look right.
The thing to notice is how the fossil sits in the rock. This is a different kind of rock than
the ones in the other images shown. It is dark and dense, and made of a much finer
material. So it probably breaks differently. The fossil sits between two breaking points
in the rock. One side is lower than the other. Keep in mind that these are small
objects. I am speculating that there might have been giant ones on Mars. The invert of
this image looks rather Martian.
Grayscale and Inverted
I am not saying that this is what the knob in the Mars "worm/tube" image is.
I am only offering an example of how such protuberances might occur in nature, and how
images distort reality - and conjecture. Maybe crinoids on Mars, if they exist at all,
are totally different from crinoids on Earth. We have all seen television shows about possible life on other
planets and artists' versions, based on those environments, of such life. Perhaps crinoids or other echinoderm-like
animals of Mars did not evolve like ours. Things tend to adapt to their environment,
after all, so why would they? Maybe they did/do not live in water.
Maybe the stone lilies of Mars are land creatures, making a living from the
organisms in mud or soil - or even the atmosphere.