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Button-like, fossilized pieces of crinoid stem Ordovician limestone Batavia, Ohio, USA The earliest known crinoids come from the Ordovician. They are thought to have evolved from primitive echinoderms known as Eocystoids. Confusingly, another early group of echinoderms were also the Eocrinoid s, but that group is currently thought to be an ancestor of blastoids rather than of crinoids.

Some fossil crinoids, such as Pentacrinite s, seem to have lived attached to floating driftwood and complete colonies are often found. Sometimes this driftwood would become waterlogged and sink to the bottom, taking the attached crinoids with it. The stem of Pentacrinites can be several metres long. Modern relatives of Pentacrinites live in gentle currents attached to rocks by the end of their stem, which is fairly short.

Drawing of the calyx of the crinoid Pentacrinites

Most modern crinoids are free-swimming and lack a stem. Examples of free-swimming crinoid fossils include Marsupitsa, Saccocoma and Uintacrinus. Many fossils of free-swimming crinoids (such as Pterocoma ) are found in the Jurassic-dated Solnhofen limestone of Solnhofen in GermanyThe Federal Republic of Germany ( German: Bundesrepublik Deutschland is one of the world's leading industrialized countries, located in the middle of the European Union. It is bordered to the north by the North Sea, Denmark and the Baltic Sea, to the east, and the CretaceousThe Cretaceous period is one of the major divisions of the geologic timescale, reaching from the end of the Jurassic period (about 135 mya) to the beginning of the Paleocene epoch of the Tertiary period (65 mya). The end of the Cretaceous also defines the-dated Niobrara chalk of KansasKansas derived from the Siouan word Kansa meaning "People of the south wind", is a midwestern state in the United States. postal abbreviation for the state is KS and the state flower is the sunflower. The state motto is "Ad astra per aspera", Latin for "t contains large numbers of Uintacrinus.

The crinoids have had an eventful geologic history. Once evolved, they soon spread to a variety of marine habitats. The group as a whole suffered a major crisis during the PermianThe Permian is a geologic period that extends from about 280 to 248 million years before the present ( mya). As with most older geologic periods, the strata that define the Permian are well identified, but the exact date of the period's start is uncertain period when most of the crinoid forms of the PalaeozoicThe Palaeozoic is a major division of the geologic timescale, one of four geologic eras. The division of time into eras, the largest division of geologic time, dates to the 18th Century. The Palaeozoic includes six geologic periods; from oldest to younges era died out, with a few surviving into the TriassicThe Triassic is a Geologic period that extends from about 248 to 202 million years (My or 'megayears') before the present. The extinction event that closed the Triassic period has recently been more accurately dated, but as with most older geologic period period. During the MesozoicThe Mesozoic is one of four (sometimes more) geologic eras. The division of time into Eras dates back to the 19th century. The Mesozoic includes three Geologic Periods; from oldest to youngest, the Triassic, Jurassic and Cretaceous. It extended from rough era there was another great radiation of the crinoids with more modern forms possessing flexible arms becoming widespread.

The long and varied geological history of the crinoids demonstrates how well the echinoderms have adapted to filter-feeding. The fossils of other stalked filter-feeding echinoderms, such as blastoids, are also found in the rocks of the PalaeozoicThe Palaeozoic is a major division of the geologic timescale, one of four geologic eras. The division of time into eras, the largest division of geologic time, dates to the 18th Century. The Palaeozoic includes six geologic periods; from oldest to younges era. These extinct groups can exceed the crinoids in both numbers and variety in certain horizons. They were evidently competing with the crinoids on an equal basis. However, none of these others survived the crisis at the end of the Permian period.

An abundance of (stemmed) crinoids occurs in the rocks of the Silurian period in the United Kingdom and the eastern United States, the Devonian period of Kentucky, Michigan, New York state and the Eifel region of Germany, the Carboniferous period of the United Kingdom, Belgium and Russia, the Mississippian period of Iowa and Indiana, the Pennsylvanian period of the mid-continental United States, the Permian period of the island of Timor, and the Triassic period of Germany.