Editing Bryozoa (section)

==== Structural polymorphs ====
Kenozooids (from the Greek {{grc-transl|κενός}} 'empty')<ref>{{cite book|last=Liddell|first=H.G.|author2=Scott R.|title=A Greek-English Lexicon|publisher=Clarendon Press|year=1940|chapter=kenos|isbn=978-0-19-864226-8|chapter-url=https://www.perseus.tufts.edu/cgi-bin/ptext?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3D%2356587|access-date=2009-08-01|archive-date=8 March 2023|archive-url=https://web.archive.org/web/20230308183237/http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3D%2356587&redirect=true|url-status=live}}</ref> consist only of the body wall and funicular strands crossing the interior,<ref name="RuppertFoxBarnesBryozoa" /> and no polypide.<ref name="Doherty2001EctoproctaInAnderson" /> The functions of these zooids include forming the stems of branching structures, acting as spacers that enable colonies to grow quickly in a new direction,<ref name="Doherty2001EctoproctaInAnderson" /><ref name="McKinneyJackson" /> strengthening the colony's branches, and elevating the colony slightly above its substrate for competitive advantages against other organisms. Some kenozooids are hypothesized to be capable of storing nutrients for the colony.{{Sfn|Taylor|2020|pp=72–73}} Because kenozooids' function is generally structural, they are called "structural polymorphs."

Some heterozooids found in extinct trepostome bryozoans, called mesozooids, are thought to have functioned to space the feeding autozooids an appropriate distance apart. In thin sections of trepostome fossils, mesozooids can be seen in between the tubes that held autozooids; they are smaller tubes that are divided along their length by diaphragms, making them look like rows of box-like chambers sandwiched between autozooidal tubes.{{Sfn|Taylor|2020|p=74}}