April 6, 2010

Researchers Investigate Spiders, Ants in Amber

Ethiopian Amber

A scientific team including students and faculty from the University of Kansas has discovered the first amber fossils from Africa. The tree resin entombed tiny parasites, predators and decomposers at a time when dinosaurs still roamed the Earth.


The amber fossil is about 95 million years old and was found in Ethiopia. It dates to a time of great change and diversification for the first flowering plants, or angiosperms. Remains of early flowering plants and ferns are preserved, as are parasitic fungi that lived on the resin-bearing trees and served as a food source for insects.

Thirteen families of insects have been found in the amber, including hymenopterans, thrips, barklice, zorapterans and remains of moths and beetles. All of them are among the earliest fossil records of these groups from Africa. Particularly intriguing are the oldest African ant and a sheet-web-weaving spider.

Twenty researchers from Germany, France, Austria, Ethiopia, Italy, the United Kingdom and the United States investigated the amber, its contents and the geological setting. Team members from KU were graduate student Erin Saupe, former postdoctoral student Vincent Perrichot and Paul Selden, the Gulf-Hedberg Distinguished Professor of Geology. The research was published in the April 5 edition of the Proceedings of the National Academy of Sciences.


The KU team investigated the ant and spider specimens in the amber. The fossils will be extremely important in understanding the evolutionary history and biological distribution of these lineages. One specimen, a spider, is the second-oldest sheet-web weaving spider (Linyphiidae) discovered to date and only the third fossil spider species to be described from the African continent. Similarly, the ant is one of the oldest representatives of this now diverse and ecologically dominant group and the earliest from Gondwana.

Ethiopian amber is unusually clear and colorful. The largest pieces reach a size of 25 cm.

Most ambers are found in North America and Eurasia. In contrast, few ambers have been found on the southern continents that formerly formed Gondwana, making the Ethiopian deposit particularly scientifically valuable. Researchers will now study the amber fossils in detail, revealing new insights into the evolution of various groups of organisms.