Simulation · Biology · Class 12
Darwin's finches: one ancestor, many beaks
From the lesson Adaptive radiation in Evolution. Change the values and watch what happens.
Darwin's finches: one ancestor, many beaksBiology · Class 12
The idea behind it
NCERT §6.4
- On his voyage Darwin visited the Galapagos Islands and saw an amazing diversity of creatures, above all small black birds later called Darwin's finches.
- Many varieties of finch lived on the same island. Darwin conjectured that all evolved on the island itself.
- From the original seed-eating form, others with altered beaks arose, letting them become insectivorous and vegetarian finches.
- Adaptive radiation: the evolution of different species in one geographical area, starting from one point and radiating out into other habitats. Darwin's finches are the textbook example.
- Australian marsupials are another: many different marsupials evolved from one ancestral stock, all within the Australian island continent.
- When more than one adaptive radiation seems to have taken place in an isolated area (in different habitats), it can be called convergent evolution.
- Placental mammals in Australia also radiated into forms that each look similar to a matching marsupial, for example the placental wolf and the Tasmanian wolf (a marsupial).