Lecture 3: Natural Selection. EEES 3050. Review. Darwin’s Five Theories 1 – The non-constancy of species The idea of a changing world can be considered the fact of evolution. 2 – The descent of all organisms from common ancestors 3 – Gradualism (no saltations, no discontinuities)
Natural selection is both!
However ... other factors also are important
But, melanism is decreasing with cleaner air!
Recommended reading: Darwin’s Finches by D. Lack 1947
‘Now! Now!’ cried the Queen. ‘Faster! Faster!’ And they went so fast that at last they seemed to skim through the air, hardly touching the ground with their feet, till suddenly, just as Alice was getting quite exhausted, they stopped, and she found herself sitting on the ground, breathless and giddy.
The Queen propped her up against a tree, and said kindly, ‘You may rest a little now.’
Alice looked round her in great surprise. ‘Why, I do believe we've been under this tree the whole time! Everything's just as it was!’
Brown & Lomolino, 1998
Rats, coyotes, cockroaches and humans
Recommended readings: Guns, Germs and Steel and Collapse by Jared Diamond