I've had several posts about the Ebola virus. That's because it's important. With that said, the virus may die down and go away. Or it may just explode and completely destroy the undeveloped world.
Whether or not the Ebola virus explodes, in the few areas where it has ravaged the population we can see how a worldwide pandemic of a deadly disease can literally cause the entire human species to evolve as those with certain traits survive while others die.
For example, Nicholas Wade argues in A Troublesome Inheritance: Genes, Race and Human History that for hundreds of years Britain existed in a Malthusian Wringer that eventually made the entire population less violent, less impulsive, more willing to delay gratification and so on. Essentially over several hundred years those with genes which encouraged traits necessary for the Industrial Revolution slowly populated all of British society.
But with the Ebola virus, altruism often results in almost certain death. Thomas Eric Duncan, the Liberian who arrived in Dallas with the disease, contracted it by trying to help a sick neighbor get to a hospital. He was unsuccessful. When the neighbor collapsed in the street bleeding from the mouth he carried her into her home and laid her on her bed. Certainly he must have known of the danger involved. A number of people tried to help the woman that day; all of them contracted Ebola. If Duncan had simply stayed within his home and ignored the woman he would probably still be alive today.
To date there have only been 4,000 Ebola deaths, but the possibility exists that this number will balloon into the hundreds of thousands or millions or even hundreds of millions. A disproportionate number of these victims will be those who tried to care for others. More than ten percent of those who have contracted the virus have been health care workers.
Those who are the most altruistic will be more likely to die; those who are the most self-protective will be more likely to live. The most altruistic people will never pass on their genes to the next generation; those with a greater proclivity for self-preservation will. In areas where 20 percent or more of the population dies from the Ebola virus, the very genetic fabric of society will be changed.
Altruism will still survive, of course. And kindness and selfishness aren't entirely genetically determined or perhaps even mostly genetically determined. But genetics plays a roll, and if most of the altruistic people are killed off by disease the remaining gene pool will be dramatically changed.
What we may be witnessing is evolution in action. It's a reminder that evolution doesn't take millions of years. Sometimes it only takes a few days or months.