Patterns of Growth anD Evolution

Macroevolution Creates NEW Species

Adaptive Radiation aka Divergent Evolution Single species or a small group of species becomes different species Ex. Galapagos Finches

Unrelated organisms come to resemble one another: similar environments Convergent Evolution Unrelated organisms come to resemble one another: similar environments

North American cacti Euphorbias in Southern Africa Convergent Evolution North American cacti Euphorbias in Southern Africa http://images.google.com/imgres?imgurl=http://www.micro.utexas.edu/courses/levin/bio304/evolution/convergent.ex1.gif&imgrefurl=http://www.micro.utexas.edu/courses/levin/bio304/evolution/macroevol.html&h=405&w=350&sz=115&hl=en&start=12&um=1&tbnid=FeV6DLuetThgTM:&tbnh=124&tbnw=107&prev=/images%3Fq%3Dconvergent%2Bevolution%2Bof%2Bcacti%26svnum%3D10%26um%3D1%26hl%3Den%26rls%3DGGLB,GGLB:1969-53,GGLB:en%26sa%3DN

Punctuated Equilibrium Patterns of long, stable periods interrupted by brief periods of rapid change. Due to environmental pressures.

Punctuated Equilibrium

Slow, constant, gradual change over long periods of time Gradualism Slow, constant, gradual change over long periods of time

Gradualism Certain moths in one population gradually adopt changes in color and wing shape. After a great deal of time, the two groups of moths develop into entirely distinct species from one another.

Two species evolve in response to changes in each other Coevolution Two species evolve in response to changes in each other

Rough skinned newt has enough toxin to kill everyone in this room Coevolution Rough skinned newt has enough toxin to kill everyone in this room The garter snake has evolved immunity to the toxin secreted in its skin http://www.zo.utexas.edu/faculty/sjasper/images/30.18.jpg

Coevolution Bumblebees and the flowers the they pollinate have co-evolved so that both have become dependent on each other for survival.

Coevolution Praying Mantis simulates plant to protect itself from predators and eats pests that are attracted to and feed on the plant, so it protects the plant. http://www.zo.utexas.edu/faculty/sjasper/images/30.18.jpg

Coevolution Shrimp cleaning Titan triggerfish in Pacific Ocean http://www.zo.utexas.edu/faculty/sjasper/images/30.18.jpg

Geographic isolation

Biological Resistance Mutations make some organisms resistant to a toxin (antibiotic or pesticide)

Evolutionary Time Scales Microevolution: Short time scale events (generation-to-generation) that change the genotypes and phenotypes of populations