The fossil record offers a narrow window through which we try to glimpse
vast vistas. Beings with hard parts have favored histories. Dates of evolutionary
events are known to varying degrees of accuracy.
Life is a story of permanence and change. Exuberant and innovative, it
is also deeply conservative. Traditions and relationships of life today
provide clues to the past. DNA is a tangled repository of ancient history;
its sequences reveal the presence of the past. Like evolutionary wax tablets,
they reveal layers of time and change.
Evolution connotes "change" over time, not "progress." How recently an
organism evolved does not define its "worth." While some organisms may
be more specialized or complex, all share an equally long evolutionary
history.
Evolution is not linear. Organisms and species do not just evolve or
become extinct--they also anastomose (fuse together). In profoundly moving
ways, life often grows in on itself, bringing previously evolved beings
together into new partnerships.
