It was a fine morning on the edge of the range at Webb Park. Noisy miners and magpies were the dominant bird sounds.
We discussed the origins of birds from a small bipedal dinosaur/reptile archeopteryx, fossils of which had been found in limestone in Bavaria. Although it had a long tail, teeth and reptile-like feet, it also had feathers and perhaps started with gliding.
Birds have a distinct keep on the breastbone to support a large breast muscle. Their 4 toes are arranged with 3 forward and one back.
Birds have diverged into over 8000 species over time. This genetic diversification requires separation and genetic isolation, which occurs as they move to different ecological niches/habitats/food supplies. This adaptive radiation occurs through mutation and recombination of genes.
Darwin found 11-12 species of finches in the Galapagos Islands - all originating from one species on the mainland.
There are about 800 species in Australia and 250 identified in Toowoomba.
Extinction also occurs; there have possibly been over a million species over time.
Habitat. Cayley's Field Guide to Australian Birds in 1931 was based on habitats. Locally we have forest habitats based on the amount of light getting through the canopy to the ground.
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