scientific doctrines may have overlooked. Instead of numbering the chimpanzees she observed, she gave them names such as Fifi and David Greybeard, and observed them to have unique and individual personalities, an unconventional idea at the time. She found that "it isn’t only human beings who have personality, who are capable of rational thought [and] emotions like joy and sorrow". She also observed behaviours such as hugs, kisses, pats on the back, and even tickling, what people consider identifiable human actions. Goodall insists that these gestures are evidence of “the close, supportive, affectionate bonds that develop between family members and other individuals within a community, which can persist throughout a life span of more than 50 years.” These findings suggest similarities between humans and chimpanzees exist in more than genes alone but can be seen in emotion, intelligence, and family and social relationships. Goodall’s research at Gombe is best known to the scientific community for challenging two long-standing beliefs of the day: that only humans could construct and use tools, and that chimpanzees were passive vegetarians. While observing one chimpanzee feeding at a termite mound, she watched him repeatedly place stalks of grass into termite holes, then remove them from the hole covered with clinging termites, effectively “fishing” for termites. The chimps would also take twigs from trees and strip off the leaves to make the twig more effective, a form of object modification which is the rudimentary beginnings of toolmaking. Humans had long distinguished ourselves from the rest of the animal kingdom as "Man the Toolmaker". In response to Goodall’s revolutionary findings, Louis Leakey wrote, "We must now redefine man, redefine tool, or accept chimpanzees as human!" Over the course of her study, Goodall found evidence of mental traits in chimpanzees such as reasoned thought, abstraction, generalization, symbolic representation, and even the concept of self, all previously thought to be uniquely human abilities. In contrast to the peaceful and affectionate behaviours she observed, Goodall also found an aggressive side of chimp nature at Gombe. She discovered that chimps will systematically hunt and eat smaller primates, such as colobus monkeys. Goodall watched a hunting group isolate a colobus monkey high in a tree and block all possible exits, then one chimpanzee climbed up and captured and killed the colobus. The others then each took parts of the carcass, sharing with other members of the troop in response to begging behaviours.