7.10.B—Describe the rate of evolution and speciation under different ecological conditions

Describe the rate of evolution and speciation under different ecological conditions.

• Punctuated equilibrium is when evolution occurs rapidly after a long period of stasis. Gradualism is when evolution occurs slowly over hundreds of thousands or millions of years.
• Divergent evolution occurs when adaptation to new habitats results in phenotypic diversification. Speciation rates can be especially rapid during times of adaptive radiation as new habitats become available.
• Convergent evolution occurs when similar selective pressures result in similar phenotypic adaptations in different populations or species.