One of the leading health threats to humans is cancer. However, wild animals rarely get this disease. Why are humans more at risk of developing cancer? When humans became bipedal in Africa, they also developed bigger brains. It seems this created the ideal conditions for cancer cell growth. This episode discusses how humans should deal with the battle against cancer within the context of the evolutionary process.
The human brain has undergone dramatic evolutionary advances. Today, however, many people suffer from strokes -- the rupturing of blood vessels in the brain. The truth is, humans suffer from strokes because brain size increased too rapidly during the course of human evolution. The blood supply to our brains increased threefold during the last 2.5 million years, but the walls of our blood vessels didn't adjust to this change and remain fragile. In addition, changes in lifestyle and dietary habits continue to cause damage to blood vessels. The hidden secrets of strokes in light of evolution are explored in this episode.
Depression is a condition that arises throughout the world. As scientists begin to understand more about the causes of depression, a surprising discovery has been made with the help of fish, our primitive ancestors. Scientists discovered that under certain conditions, the part of the fish brain that works to protect them from natural predators goes out of control and causes depression. When mammals began living in groups, they developed traits that lead to a similar, poorly regulated response in the brain. This program reveals the evolutionary reasons behind why humans develop depression and introduces the latest treatments based on these discoveries.
The World Health Organization claims heart disease is the leading cause of death in the world. Could evolution be key in understanding this disease? Over 220 million years, mammals gradually acquired outstanding athletic ability through incremental improvements in the heart. However, 7 million years ago, several stages in early human evolution caused the development of heart disease risk factors. For example, by standing upright, the burden on the heart was increased, and in exchange for our larger brain, the seeds of heart attacks were planted. This program examines how the human predisposition for heart disease was the price for evolution.