Animal mesoderm forms by enterocoelic pouching, through invagination of the endoderm. The main deuterostome phyla are the Echinodermata and the Chordata. Echinoderms are exclusively marine and include starfish, sea urchins, and sea cucumbers. The chordates are dominated by the vertebrates (animals with backbones), which consist of fishes, amphibians, reptiles, birds, and mammals. The deuterostomes also include the Hemichordata (acorn worms). The Ecdysozoa are protostomes, named after their shared trait of ecdysis, growth by moulting. They include the largest animal phylum, the Arthropoda, which contains insects, spiders, crabs, and their kin. All of these have a body divided into repeating segments, typically
Subgroups of Amish Amish". In the following, subgroups of Old Order Amish are listed from conservative to progressive: The Nebraska Amish are perhaps the most conservative group of Old Order Amish. They live mostly in Pennsylvania but they also have one small settlement in Ohio. Around 1880, Bishop Yost H. Yoder led nine families from Juniata County, Pennsylvania, to Gosper County in south-central Nebraska, founding an "Old Order" settlement that would last until 1904. Yoder went back to the Kishacoquillas Valley in Pennsylvania in 1881 to assist a conservative Amish group. Because bishop Yoder was living in Nebraska for some time, and the