Echinoderms of the Iowa Devonian

Epibionts from the Cerro Gordo Member of the Lime Creek Formation (Upper Devonian), Rockford, Iowa

Hydrogeology of the Devonian-Silurian Carbonate Aquifer, Northern Cedar Rapids, Iowa

Echinoderms

two fish. In the wild, kittiwakes have to learn to look for particular colours and patterns in the ocean to find the best place to fish. The researchers tried to recreate this for the captive birds by making them search for their food among a chequerboard of different coloured bowls. Chicks on the unrestricted fatty diet quickly learned which bowls contained food, but chicks on lean rations wer...

Epizoans and Predation Traces of Devonian Hay River Formation Brachiopods: Indicators of Complex Ecosystems and Ties to the Iowa Basin

Two brachiopod communities from the Devonian Hay River Formation units B and C are moderately to heavily encrusted by epizoans. The unit B community bears evidence of predatory attacks. This community was much more diverse in terms of host brachiopods and attached epizoans; furthermore, epizoans were highly abundant. Predation traces occurred only on brachiopod species that were heavily encrust...

Echinoderms Have Bilateral Tendencies

Echinoderms take many forms of symmetry. Pentameral symmetry is the major form and the other forms are derived from it. However, the ancestors of echinoderms, which originated from Cambrian period, were believed to be bilaterians. Echinoderm larvae are bilateral during their early development. During embryonic development of starfish and sea urchins, the position and the developmental sequence ...