Paleobotany, the study of the plant fossil record, documents past vegetation changes and diversity, including evidence of extinct forms. Recent advances in paleobotany reveal much about the phases of diversification of embryophytes (plants that produce embryos), and demonstrate that living embryophytes represent a very small proportion of their former diversity. Through integrative consideration of living and fossil forms, an accurate picture of embryophyte evolution and reliable reconstruction of their phylogeny (relationships by ancestry) are being sought.