Giribet & Wheeler (2001) showed that the general pattern of 18S evolution across a much broader sampling of taxa, including hexapods, chelicerates, myriapods
, and crustaceans, is one of conserved length in the 1800 by range, with occasional increases in size.
Topics in this portion include leg amputation and regeneration, ballooning, bleeding, camouflage, webs, sperm and sperm webs, courtship behavior, egg sacs, enemies, fecal remains, exuviae, ant mimicry, wound healing, molting, cannibalism, parasitism, phoresis and predation by spiders on a wide range of other organisms (including beetles, flies, bark lice, ants, planthoppers, termites, other spiders, caddis flies, parasitic wasps, scale insects, spring tails, roaches, aphids, mites, a web spinner, weevils, bristle tails, insect larvae, myriapods
According to the traditional view, the myriapods
are most closely related to the insects (common taxon "Tracheata" or Antennata), the crustaceans are the closest relatives of the Antennata (common taxon Mandibulata), and the chelicerates are the sister group of the Mandibulata.
The East Kirkton locality has also yielded scorpions (Jeram 1994, 2001), myriapods
(Shear 1994) and a variety of terrestrial tetrapods including the anthracosaurid Silvanerpeton miripedes and the famous stem-amniote Westlothiana lizziae; however early insects and arachnid groups like the extinct order Trigonotarbida, which are usually fairly common in terrestrial deposits of this age, are so far absent.