The Megalodon, a prehistoric giant shark, is believed to have gone extinct around 2.6 million years ago. There are several factors that likely contributed to its extinction:

1. Environmental Changes: 

In that ancient time, the earth became so cold that when ocean temperatures dropped, the distribution and abundance of marine life, including species of the Megalodon such as whales, may have been affected by food sources and breeding grounds.

2. Competition: As the earth's ecosystem changes, megalodon species compete for food sources with other sea animals. Increasing sea animals' population , megalodon could have pressured on the megalodon population.

3. Decline in Prey: Megalodon eats mostly on huge marine creatures like whales. Variations in the distribution or amount of these prey species may have affected the Megalodon's capacity to find food.

4. Evolutionary Pressures: Over time, the Megalodon's large size and energy requirements may have become a disadvantage as food sources became scarcer. Smaller, more adaptable species may have had a survival advantage.

5. Other Factors: Other factors, such as disease, parasites, or changes in ocean chemistry, could have also played a role in the Megalodon's extinction.

While the Megalodon was a significant and powerful predator at that time, no species is immune to extinction, particularly in the face of major environmental changes and competition among other species.