SABER-TOOTHS: WHAT, WHEN, HOW, AND WHY: A WORKSHOP APPROACH TO THE ENIGMA
William Akersten
During the past 50 million years, at least five lineages of carnivorous mammals, from marsupials through the primitive placental creodonts to the derived placental carnivores have evolved saber-tooth characteristics only to become extinct - none exist today. Paleontologists and the general public have long been fascinated by the extreme, even bizarre, adaptations of saber-toothed mammals. This interest often led to equally bizarre hypotheses as to the use of the saber-like upper canine teeth including melon slicing, walrus-like mollusk grubbing, blood sucking, and tree climbing aids analogous to linesmen spurs. In both the scientific and popular literature, saber-toothed carnivores have often been lumped as a single phenomenon or ecomorph. While certain major basic morphologic patterns are common to saber-toothed carnivores, recognition and interpretation of differences in detail among the various kinds have gained prominence during the past several decades. At the same time that it is becoming more obvious that saber-tooths can serve as exemplars of adaptation and evolution, it is at least equally obvious that the scientific literature yields only partial and sporadic insights into these unique creatures. But what questions can potentially be answered, or at least attacked, through a better understanding of saber-toothed carnivores? What is the meaning of the variations on the basic saber-tooth morphology and do they constitute meaningful patterns? Why and how did the saber-tooth morphology evolve so many times in different groups of carnivorous mammals living at different times on different continents only to become extinct each time while apparently suitable prey survived? What effect did their extinction have on other highly carnivorous mammals and on the herbivores which survived them and can their extinctions shed some light on the potential effects of the reduction and possible ultimate loss of many modern large carnivores? Not only do saber-toothed carnivorous mammals pose intriguing and important research questions, the public fascination with the oversized upper canines of saber-tooths provides an unusual opportunity to use these extinct mammals to illustrate major biologic concepts including evolution, paleogeography, homology, and functional morphology. Much has been written regarding certain aspects of the functional morphology and convergent evolution of saber-toothed carnivores, but their potential has barely been touched. Saber-tooths frequently been treated in the paleontologic literature as bearers of morphologic features, rather than as integrated organisms. A major reason for this lack of cohesiveness is that the various researchers working on saber-tooths are scattered on several continents as are the remains of the objects of their researches. Another reason is that there has never been one occasion during which a significant number of saber-tooth students have been able to interact to develop a vision for future work, especially collaborative efforts, combining the newest methodologies with standard approaches, and viewing sabertoothed carnivores from a ?holistic? perspective. This three day international workshop, May 12-14, 2008 on the campus of Idaho State University, Pocatello, Idaho will increase our knowledge of saber-toothed mammals through improved communications, better sharing of information among researchers, facilitating cooperative and multidisciplinary studies and advancing our ability to view saber-tooths as dynamic, integrated organisms. Public education goals include methods of utilizing saber-tooths as models for public education in evolutionary processes, extinction, homology and analogy, paleoecology, and geologic time.
