<span>1. Introduction of a different environmental pressure, like an invasive species or a prolonged natural disaster.
2. Random mutation, where a gene or set of genes in an individual organism is randomly different from the normal type of that gene in the larger population. This individual may gain an advantage from this mutation and its offspring will inherit the advantageous trait.</span>
Then it is a cancer cell. Cancer cells divide without restrainments ( free for all), attacking the body, and killing organisms. :)
Explanation:
11.099 births per 1000 people
STI stands for Sexually transmitted infection.
