Insects in Amber

Abstract

Aside from their beauty, insects in amber represent the finest fossil remains of the Insecta and offer numerous opportunities to study microevolution, biogeography, mimicry, behavior, environmental reconstruction, extinction, paleosymbiosis, and molecular phylogeny. Amberization (changes involved in the process of forming amber from fresh resin) is a gentle process inducive to the preservation of insects that are small, delicate, and soft-bodied. It is the most complete type of fossilization known for insects, and by preserving the three-dimensional form, color pattern, and minute details of the exoskeleton, such fossils can be easily compared with their extant descendants. The study of amber insects was initiated over 200 years ago with the fIrst investigation of the Baltic amber fauna and flora (10). Indeed, most of the descriptions of amber insects today pertain to Baltic deposits. However, in the past 50 years, workers have begun to explore additional amber deposits. These are listed in Table 1. The oldest amber deposits containing insects are from the Middle East and are commonly known as Lebanese amber. They date from the Early Cretaceous and extend back 135 million years. In the past 20 years, attention has centered on the highly fossiliferous Tertiary amber deposits in the Dominican Republic, which are fairly extensive and provide a steady income for Dominican workers primarily through sale for use as jewelry. Because of the scientific interest of specimens from these deposits, their availability, and the range of insects represented [some 235 families at present (13)], this review emphasizes Dominican Republic (or Dominican) amber insects. Amber forgeries can suddenly appear and look very authentic. Forgeries involve the placement of present-day insects into plastic or semi-fossilized