For Immediate Release Contact: Nancy O'Shea (312) 665-7103 (For Media Use Only) Field Museum Scientists Featured in Evolving Planet Robert D. Martin, PhD Anthropology Department Curator, Biological Anthropology and Provost, Academic Affairs Biological anthropologist Bob Martin has devoted his entire career to exploring the evolutionary tree of primates. In addition to our own species Homo sapiens, the order Primates contains about 350 other living species, ranging from lemurs to monkeys to apes. In addition, there are almost 500 fossil species dating back as far as 55 million years ago. In his quest to achieve a reliable reconstruction of primate evolutionary history, Martin has studied an extensive array of characteristics in the living species, including anatomical features, physiology, chromosomes and DNA. Martin has been particularly interested in the brain and reproductive biology, as these systems have been of special importance in primate evolution. With skeletal features, it is possible to include the fossil evidence and thus to include geological time in the picture. By studying living primates in the field in the forests of Africa, Madagascar, Brazil and Panama, Martin has also been able to include behavior and ecology in an overall synthesis. That synthesis was first presented in his textbook Primate Origins and Evolution, published by Princeton University Press in 1990. Since then, Martin has been working on various refinements. “A proper understanding of primate evolution provides an essential basis for interpreting the special case of human evolution,” Martin says. “Without this secure foundation, it is exceedingly difficult to produce convincing explanations for the evolution of all of our special features. If we restrict ourselves to comparisons of humans and our closest relatives, the great apes, we are continually forced to draw conclusions that have no generality and are not testable. “One good illustration of the need for broad comparisons is provided by investigations of the timescale for primate evolution,” Martin continues. “Although the earliest known primate fossils are only 55 million years old, our statistical analysis allowing for gaps in the fossil record indicates that primates actually diverged from other mammals about 90 million years ago. When this result is applied to the specific case of human evolution higher up in the tree, it emerges that our lineage probably branched away at least 8 million years ago, earlier than previously thought.” Continue>>