Most stalked crinoid
fossils depict spindly, plantlike animals anchored to sea floor rocks, explains earth scientist William Ausich, coauthor of a study in Geologica Acta.
The stalked crinoid spends most of its time sitting and catching food with the flowerlike wheel of feathery arms that have earned it and its relatives the nickname sea lilies.
A stalked crinoid pulled itself along the bottom briskly enough for a viewer to notice.
Two decades ago, Baumiller and Messing independently documented movement by some stalked crinoids.
Specimens of the stalked crinoid Metacrinus rotundus Carpenter, 1882, were dredged from depths of 100-150 m in Suruga Bay off Numazu, Japan.
The simultaneous measurement of isotonic contraction and tissue stiffness revealed that the arm of a stalked crinoid from which arm muscles had been removed simultaneously shortened and changed in stiffness in response to chemical stimulation.
The hypothesis that comatulid crinoid arms are more flexible than stalked crinoid arms could be directly tested in extant crinoids by using the techniques developed in this study.
Passive orientation of entire organisms has been described in gorgonian corals (Theodor and Denizot, 1965; Wainwright and Dillon, 1969) and in stalked crinoids (Baumiller and Plotnick, 1989), although the mechanisms differ in these two systems.
Several species of stalked crinoid were observed from Johnson-Sea-Link (JSL) submersibles at depths ranging from 400 to 900 m in the northern Bahamas (see map in Young, 1992).
Our observation of apparent jux-taligamental cells [ILLUSTRATION FOR FIGURE 5B OMITTED] is equivocal evidence for mutable collagenous tissues in stalked crinoid arms.
Chiefs at Seahawks (-3): If Gunther Cunningham were not a football coach, I believe he would be a marine biologist specializing in the sleeping patterns of pycnogonid sea spiders and stalked crinoids
rotundus may not even represent all members of the stalked crinoids
, the class to which the species belongs.