81.   There is nothing a human has that a rattlesnake really needs.

82.   These humans had a confined tool kit.

83.   They found the viral strain had two major proteins against which humans have little or no immunity.

84.   We might think that facial expressions are redundant now that humans have language, an infinitely superior tool for expressing ideas and concepts.

85.   What would happen if humans had the same contact with feces that dogs do?

86.   While scientists accept that most animals send and receive pheromones, some doubt that humans have the same ability.

87.   Although the work only has been demonstrated in laboratory animals, Petersen said other studies strongly suggest humans also have bone marrow cells that will convert into liver cells.

88.   An average human has five to seven litres of blood in the body.

89.   Humans have generous amounts, while large primates such as chimpanzees have less and small monkeys even smaller amounts.

90.   Humans have white blood cell counts similar to those in primarily monogamous species, the researchers said.