Firstly, a quick note about the images, I took the first 3 photos. The featured photo is a view of the Second Hosie Limestone, on Seafield Castle Beach, near Kirkcaldy, looking south over the Firth of Forth towards East Lothian. The second and third photos show crinoid stem fragments (white) in the muddy (dark) Second Hosie Limestone. The last two photos are public domain images, the first of which shows a museum specimen of a full crinoid/sea-lily, the second portrays how geologists imagine that sea-lilies would have looked like.
These crinoid fragments are relatively transient, in the grand scheme of things, they once flourished on the seafloor, approx 323 million years ago, they then died and the stems broke up (photos 2 and 3). At this point in time, this part of what we now call Scotland, lay somewhere near the equator. The crinoids were then buried (probably to a depth of many thousands of feet), in an organic rich calcareous mud (note black colour of the matrix of the rock). Over a period of millions of years, the limestone was gradually uplifted again, and is at the present time, now getting eroded again, and the sea-lily/crinoid stem fragments are once more about to return to the sea floor. This whole process has taken approx 325 million years, which seems an incredibly long time, but is just a transient moment compared to the age of the universe (13.8 billion years).
And modern human beings are even more ‘transient’ in nature, having been around for just a mere 200, 000 years!!