This tree diagram shows the relationships between several groups
of organisms. The root of the current tree connects the
organisms featured in this tree to their containing group and
the rest of the Tree of Life. The basal branching point in the
tree represents the ancestor of the other groups in the tree.
This ancestor diversified over time into several descendent
subgroups, which are represented as internal nodes and terminal
taxa to the right. You can click on the root to travel down the
Tree of Life all the way to the root of all Life, and you can
click on the names of descendent subgroups to travel up the Tree
of Life all the way to individual species.close box Agustí, J.
and M. Antón. 2002 Mammoths, Sabertooths, and Hominids: 65
Million Years of Mammalian Evolution in Europe. Columbia
University Press, New York. Allard, M. W., R. L. Honeycutt, and
M. J. Novacek. 1999. Advances in higher level mammalian
relationships. Cladistics 15:213-219. Alroy, J. 1999. The fossil
record of North American mammals: evi