Question

The diversity in the type of beaks of finches adapted to different feeding habits on the Galapagos Islands, as observed by Darwin, provides evidence for
A. Intraspecific competition
B. Interspecific competition
C. Origin of species by natural selection
D. Origin of species by mutation

Answer 1

Darwinism is a theory of biological evolution founded by the English naturalist Charles Darwin (1809-1882) and others, arguing that through the natural selection of small, inherited variations that increase the capacity of the individual to compete, survive, and reproduce, all species of organisms arise and evolve.

Complete Answer:
During his famous voyage, Darwin found that the finches of the various Galapagos Islands had beaks of various sizes and shapes. He found that this was due to adaptation to various types of food available. He concluded that in the absence of competition, the ancestral finches filled all vacant ecological niches upon reaching various islands and evolved into different species. This provides proof for the origin of species by natural selection.

So,' Origin of species through natural selection' is the right answer.

Additional information:
- Darwin's finches consist of 18 different species of birds. These birds are known for their diversity in beak forms as well as functions. These are classified as subfamily Geospizinae. They are known to belong to the tanager family and are thought to be not closely linked to the true finches.
- Darwin's finches are known to be a classical example of adaptive radiation. It was observed that change in the beak size and form enabled different species of finches to have different foraging activities e.g. insects, seeds, nectar from cactus flowers as well as blood from iguanas.

Note: The theory of Darwin had two main points; 1) there are diverse groups of animals evolving from one common ancestor; 2) there are mechanisms which are responsible for evolution to take place which is called natural selection.