Ontogenetic Shape Change in
Agnostid Trilobites from the Wheeler Shale
In almost all animals, juveniles look very different than adult individuals. Puppies look different than adult dogs. Bear cubs are easy to tell from full-grown grizzlies. Does the same hold true for trilobites? By picking out discrete points on the carapace of a trilobite and seeing how those points move relative to one another in trilobites of different sizes, it is possible to see how the appearance of these ancient creatures subtly changed throughout their lifetimes.