Darwin's Finches Jinny

Darwin's Finches

Introduction

Charles Darwin
=Naturalist
-Father of evolutionalist theory
-Survival of fittest

What is Darwin's Finches
-Group made up of 13 species of passerine birds
-They were no known as Darwin's Finches until 1936 ,popularized by ornithologist

What is Darwin's Finches
-Darwin's finches is group made up of 13 species of passerine birds

History
-All of Darwin's Finches evolved from one ancestral species
-The ancestral species arrived South American mainland around 2 or 3 million years ago

In late December of 1831
-Darwin and his HMS Bragle went on voyage around South America
-His aim was to observer and collect samples of loval flora and fauna

=At the Galapagos Islands, off the coast of Ecuador was where his finding began

Variety
-There were variations of the finches from island to island
-Their beaks amde ot difficult to differentiate them

-Ground finch
-Woodpecker finch has evolved a bust brak to drill holes in tree and eat beetle larvaes
-Cactus finch has longer sharp pointed beaks to feed on cactuses
Tree finches

They mostly feed on insects
Warbler finch has a very fine needle-like beak to picking off insects

Causation
-This phenomenon is called the character displacement
-Animals experience evolutionary change to minimize competition with the food
-The path of a weather system "El Nino" affected the islands
-Sometimes extreamely hot and dry and sometimes rainy for the whole month
-This caused the shortage of seeds on the island -> increase in competition
-The small beaked birds becamse weak to survive -> by the end of the drought period, their beak depth was increased by 1 mm
-Then the finches began to spread around in new habitats and specialise on different ways of feeding