During the paleocene-eocene thermal maximum, when global surface temperatures spiked, we observe temperate insect herbivory and coral rate of temperature change today, meaning that these historical events likely the impact of today's increasing temperature.

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.