The Black Death is considered as the deadliest pandemic in history. There were four main forms of this plague namely: bubonic, pneumonic, septicemic and enteric plague. It wiped out around 200 million people from Europe and Asia. It was caused by yersinia pestits, a type of bacteria transmitted through flea bites or inhalation. One of the main reasons why the plague spread quickly was the terrible health condition of the city dwellers due to poverty and malnutrition. The great famine of 1315 struck many parts of Europe and it lasted for almost seven years. The famine ultimately weakened the immune system of the dwellers in the cities.
This process is natural selection<span>. The traits that confer an advantage to those individuals who leave more offspring are called </span>adaptations<span>. In order for </span>natural selection<span> to operate on a trait, the trait must possess heritable variation and must confer an advantage in the competition for resources.</span>
The "Holy Experiment" was an attempt by the Religious Society of Friends, also known as Quakers, to establish a community for themselves and other persecuted religious minorities in what would become the modern state of Pennsylvania.
It caused them to be slaves
