Table of Contents
Adaptive radiation & Endemic species on islands
Adaptive radiation
When does radiation occur?
Galapagos finches
The origin of the finches
The Galapagos lie 800-1100 km west of Ecuador
Darwin collected Galapagos finches during his voyage on the Beagle
The importance of Darwin’s finches
The variety of finches
The beaks!
The evolution of the finches
Ground finches
Cactus finches
Tree finches
The woodpecker finch
The Hawaiian islands
Hawaii is extremely isolated & is over 4000 km from the nearest continental land
This extreme isolation and consequent low rate of arrival of species has resulted in a degree of endemism unmatched anywhere else in the world.
The Hawaiian honeycreepers form an endemic family! - the Drepanididae
The drepanids
When did the ancestors of the drepanids arrive?
How many species are there?
Finch-like drepanids e.g. Psittirostra & Pseudonestor
Nectar-eating drepanids e.g. Loxops & Drepanis
Insect-eating drepanids e.g. Paroreomyza & Hemignathus
A conservation nightmare?
Known extinctions of species on islands & continents since AD 1600
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