NEET BIOLOGY

Detailed explanation-1: -Darwin concluded that organisms on the Galápagos Islands . . . had changed over time. How does natural selection lead to evolution? Helpful variations accumulate among surviving members of the species.

Detailed explanation-2: -Over time, Darwin began to wonder if species from South America had reached the Galapagos and then changed as they adapted to new environments. This idea-that species could change over time-eventually led to Darwin’s theory of evolution by natural selection.

Detailed explanation-3: -Darwin proposed that species can change over time, that new species come from pre-existing species, and that all species share a common ancestor. In this model, each species has its own unique set of heritable (genetic) differences from the common ancestor, which have accumulated gradually over very long time periods.

Detailed explanation-4: -The theory of natural selection was explored by 19th-century naturalist Charles Darwin. Natural selection explains how genetic traits of a species may change over time. This may lead to speciation, the formation of a distinct new species.

Detailed explanation-5: -In Galapagos, the Earth’s crust is moving from west to east over the hot spot. Therefore, the islands that are furthest to the east, such as San Cristóbal, are the oldest: they were formed many thousands of years ago. Because these older islands are no longer over the hot spot, they are no longer volcanically active.