If we are more closely related to protozoans such as slime molds because they are animal-like and engulf food the way amoebas do, then what can we conclude about our own physiology? We can conclude that modern scientists have an edge on scientists of the past because we know more about molecular genetics than they did. For example, we now know that human genes can be inserted into yeast and yeast cells will function normally. This knowledge will help us understand how viruses function when they insert their genetic material into a cell and take over the cell’s machinery to produce more viruses the same way the retrovirus, HIV does.