Scientists examine the teeth of Brutus, a wolf being studied by USGS scientists, for patterns of wear that indicate age. The front incisors are worn without their lateral cusps present. The canines show some wear and are becoming rounded and stained but still maintain most of their length. One canine tip has been broken. Using published accounts of tooth wear from captive and known aged wolves as reference, scientists estimate this wolf to be 8 - 10 years old.