An Introduction to the Invertebrates, Second Edition - tiera.ru

100 NEMATODArate of nucleotide substitutions in nematode ribosomal DNA.However, emerging evidence rather surprisingly places the phylumwith arthropods and other animals with moulted cuticles (seeChapter 20).8.7 ConclusionNematodes are exceptionally uniform and widespread, combininguniformity of structure with variety of habitat. It has been said thatthere appears to be only one nematode, the model coming in varioussizes and with a great variety of life histories. Their success and theirmorphological uniformity can both be attributed to the uniquestructure and properties of the cuticle. Their developmentaluniformity, with a fixed hierarchy of cell decisions, has beenparticularly useful to biological and medical research. Our uniquelyfull understanding of the genetic regulation of development innematodes is increasingly applied to investigation of other animals,including ourselves.