Writers : Poursharifi,Kourosh
Refference : Geosciences Scientific Quarterly Journal,No.:4,P.:58

Abstract :
There have been detailed paleontologicaI studies on the quality of coiled and enrolled forms trilobit
Apart from anatomical discussions on the subject, attempts have been made to explain the origin ! causes of the above- named habits.
From the uniformitarianism point of view some simple experiments and or examples are mentioned. Although some of the trilobite groups have passed several evolutionary trends, but nevertheless oti groups remained primitive and practically unchanged. On the whole, we may conclude that, the trilobites w one of the highly developed, evolving lineages among the Invertebrata as well as perhaps being, at a partic! period of time the most advanced and developeed living creatures on the earth.
Subject List : Trilobite