When Darwin observed the tortoises on the different islands of the Galapagos Islands, he noticed that the tortoises' traits were matched to their different environments. This observation led him to formulate his theory of evolution by natural selection.
1. For example, on islands with tall vegetation, he found tortoises with long necks and limbs that helped them reach the higher vegetation for food.
2. Conversely, on islands with low vegetation, he found tortoises with shorter necks and limbs because they didn't need to reach high for food.
3. This variation in traits among the tortoises on different islands indicated that they had adapted to their specific environments over time, showcasing the concept of natural selection where traits beneficial for survival are passed down to offspring.
Therefore, Darwin's observation of the tortoises on the Galapagos Islands provided him with valuable evidence supporting his theory of evolution through natural selection.
