Evolutionary history of plants phloem on the outside. Since xylem cells comprise dead, lignified tissue, subsequent rings of xylem are added to those already present, forming wood. The first plants to develop secondary growth and a woody habit, were apparently the ferns, and as early as the Middle Devonian one species, "Wattieza", had already reached heights of 8 m and a tree-like habit. Other clades did not take long to develop a tree-like stature. The Late Devonian "Archaeopteris", a precursor to gymnosperms which evolved from the trimerophytes, reached 30 m in height. The progymnosperms were the first plants to develop true wood, grown from
Seeds of Change (album) Seeds of Change (album) Seeds of Change is Kerry Livgren's first solo album. Released in 1980 while he still was a member of Kansas, it features guest appearances by three fellow Kansas members: Steve Walsh, Phil Ehart and Robby Steinhardt. Singer Ronnie James Dio and members of LeRoux, Jethro Tull, Ambrosia, and Atlanta Rhythm Section are also featured. In 1996, "Seeds of Change" was reissued by Renaissance Records with an interview with Livgren as a bonus track. "Seeds of Change" marked a new chapter in Kerry Livgren's music. It was recorded after Kerry Livgren had converted to Christianity in 1979.