1. Darwin’s Finches Introduction :
Darwin studied finches inhabiting the 24 Galapagos Islands
He studied 13 species of Finch during 1835 what he discovered helped formulate his theory on Natural Selection
He concluded that one species of Finch originated form South America and went on to breed
From this 13 species of Finch evolved, different species of Finch live on different Islands and their beak size is dependant on their diet.

2. Darwin’s Finches General Characteristics:
They may have warbler like bills
Insect eating bills
Or heavy crushing bills for cracking hard seeds
One is a tool user using a cactus thorn to dislodge grubs from holes in trees
All are blackish or dull brownish grey
With or without streaks
They differ in size
They differ in size and shape of bill

3. Darwin’s Finches Fruit eater, Parrot-like bill, Tree finch
Insect eater,
Grasping bill,
Tree finch
Insect eater,
Grasping bill,
Tree finch.
Cactus eater
Probing bill
Ground finch
Insect eater
Probing bill
Tree finch
Insect eater
Probing bill
Warbler finch
Seed eater
Crushing bill
Ground finch

4. Darwin’s Finches Further Investigation:
Peter and Rosemary Grant studied Darwin’s theory from 1973 they studied six species of Finch living on Daphne Major Island.
They determined that depth of beak is a strong genetic component it determines what the bird can eat
During the drought in 1977 food shortage acted as a selection process, older birds, male birds and those with larger beak size were more likely to survive.
During 1978 surviving birds bred producing offspring with consequently larger beaks and darker plumage.
When food was in short supply larger birds were more likely to die than smaller birds as they required more food, the process was repeated.
This shows the process of natural selection and how this produces different species.