The molt stages of each crayfish were determined in terms of gastrolith
growth according to the molt mineralization index (MMI).
Calcium transport in crayfish gastrolith
disc: morphology of gastrolith
disc and ultrahistochemical demonstration of calcium.
In some crayfish, gastroliths
are reported to be composed of calcium carbonate in an extremely poorly crystalline state, as they do not diffract X-rays or electrons (10).
Gillette, Utah's state paleontologist, identifies the rocks as gastroliths
-- so called "stomach stones" that certain animals hold within their digestive tract to grind food.
, and the lithophagic behavior of sauropodomorph dinosaurs.
Some dinosaurs also possessed gastroliths
, perhaps for a similar reason.
The only non-molluscan fauna include two small crayfish gastroliths
. All Loess deposits are considered strictly eolian in origin.
Stomachs with calcified gastroliths
were subsequently disregarded, thereby effectively eliminating from the present study all premolt lobsters from stage [D.sup.1.5] (=[D.sub.0]) on (Aiken, 1980).
One section I found most fascinating was Chapter Six on gastroliths
You can locate the homes of big, crayfish-eating trout by keeping an open eye for gastroliths
. Crayfish require a large amount of calcium to build their shells.
n A sauropod's stomach could hold up to half a tonne and had large stones inside it - gastroliths
- to help grind down and digest the food.
One specimen (GCSU 4462) contained two crayfish gastroliths
and a few isolated legs in its gut.
This student told me, "This doesn't really have anything to do with geology, but it sure is neat!" I argued that it had strong relevance to geology and paleontology because we can use those gastroliths
as clues about diet and migratory patterns.
For example, the body mass of crocodiles and alligators that is rock gastroliths
New analyses of the gastroliths
in ostriches are casting doubt on that theory.