Among the invertebrates this need was met largely by the development of sclerotins and other cross-linked proteins that allowed insects to adapt to existence on the land and later to develop wings.
Entre os invertebrados esta necesidade solucionouse en gran medida co desenvolvemento de esclerotinas e outras proteínas con enlaces cruzados que permitiron aos insectos adaptarse á existencia en terra e posteriormente ao desenvolveren ás.