Does the size of an animal affect how fast bacteria from its feet can grow? You take bacteria samples from the feet of a chicken and a human and a rabbit. Each sample goes onto its own agar plate. You measure the area of bacterial growth once a day for three days. Three plates per animal give you an average. The chicken bacteria grew fastest on day one. But by day three the human sample had caught up. The results are not straightforward. Fur on the rabbit foot may have changed what bacteria were collected. Growth rates shifted from day to day in unexpected patterns.