comparing c. elegans to ascaris (2 different clades) - separated by 500 million years of evolution:
- c elegans is 1mm, ascaris can be 40 cm long
- ascaris have 50,000 muscle cells, c elegans have 79
- ascaris have 298 neurons compared to 302 in c elegans but the homology is incredibly high and very easy to compare
this shows invariance of nervous systems (and stereotypy) across nematode species