Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Available space theory
open-in-new
<p>In <a href="/facts/Botany/PaIRoxnb">botany</a>, available space theory (also known as first available space theory) is a theory used to explain why most plants have an alternating <a href="/facts/Phyllotaxis/8xGtgllo">leaf pattern</a> on their <a href="/facts/Plant_stem/QlQWSzV4">stems</a>. The theory states that the location of a new leaf on a stem is determined by the physical space between existing leaves. In other words, the location of a new leaf on a growing stem is directly related to the amount of space between the previous two leaves. Building on ideas first put forth by <a href="/facts/Wilhelm_Hofmeister/QDwG13xX">Wilhelm Hofmeister</a> in 1868, Snow and Snow hypothesized in 1947 that leaves sprouted in the first available space on the stem. </p>