90 Evolution and the Fossil Record
In the Dictionary of Science and Creationism, Ecker (1990:195–196) defines the issue with
transitional forms this way (capitalized words indicate other entries in the dictionary):
There are nevertheless all sorts of transitional forms in the fossil record to belie the
creationist argument that they do not exist. They exist not only at the species level
(creationists consider these only “variant forms of the same basic kind”) but between
major groups: There are intermediates between FISH and AMPHIBIAN (Ichthyoste-
ga), amphibian and REPTILE (Seymouria), reptile and MAMMAL (the mammal-like
reptiles), reptile and BIRD (see ARCHAEOPTERYX), extinct ape forms and MAN (see
AUSTRALOPITHECINES).FIGURE 3.12. We do not need to have every single transitional fossil connecting several species to
show evolutionary transformation. For example, a sequence of related species that are stable through time
nevertheless forms an evolutionary transformation series, even though not every transitional fossil has been
preserved. The evolution of sand dollars from sea urchins is an excellent example (see figure 8.13).
Geologic time