Monocot Xylem Revisited: New Information, New Paradigms Sherwin Carlquist The Botanical Review ISSN 0006-8101 Volume 78 Number 2 Bot. Rev. (2012) 78:87-153 DOI 10.1007/s12229-012-9096-1 1 23 Your article is protected by copyright and all rights are held exclusively by The New York Botanical Garden. This e-offprint is for personal use only and shall not be self- archived in electronic repositories. If you wish to self-archive your work, please use the accepted author’s version for posting to your own website or your institution’s repository. You may further deposit the accepted author’s version on a funder’s repository at a funder’s request, provided it is not made publicly available until 12 months after publication. 1 23 Author's personal copy Bot. Rev. (2012) 78:87–153 DOI 10.1007/s12229-012-9096-1 Monocot Xylem Revisited: New Information, New Paradigms Sherwin Carlquist1,2 1 Santa Barbara Botanic Garden, 1212 Mission Canyon Road, Santa Barbara, CA 93105, USA 2 Author for Correspondence; e-mail:
[email protected] Published online: 5 April 2012 # The New York Botanical Garden 2012 Abstract Five sources of data force extensive revision of ideas about the nature and evolution of monocot xylem: scanning electron microscopy (SEM) studies of thick sections; availability of molecular phylogenies covering a relatively large number of families and genera; information on ecology and habitat; data concerning habit; and observations from xylem physiology. These five new sources of data, absent from the studies of Cheadle, plus added information from light microscopy, lead to a fresh understanding of how xylem has evolved in monocots.