Researchers have discovered that within the two days after a python eats a meal, its heart grows larger by up to 40 percent. This amazing transformation is linked to the increased meatabolic rate a python experiences following a meal. Because the pythons' increased metabolism consumes more oxygen during digestion, a larger heart provides them with much needed power to pump more oxygen-rich blood per heartbeat.

Find out more: Pythons grow bigger hearts at mealtime (National Geographic)