Reminder! The flow of genetic material DNA Gene Protein Cell Tissue/Organ Organism/Traits

V. NATURAL SELECTION IN PEPPERED MOTHS Before the industrial Revolution in the late 1700’s, forests in London were covered in spotted lichen on trees Peppered (spotted) moths blended in with the lichen.

PEPPERED MOTHS Darker spotted moths were easy to be seen by predators & were eaten AFTER THE INDUSTRIAL REVOLUTION-Lichen turned black from the soot from the burning of coal. Black spotted moths blended into the darker lichen… Soon the lighter peppered moth population declined & the darker peppered moths increased. The darker peppered moths had adapted to this environmental change.

PEPPERED MOTHS CONT. 1950’S H.B.D KETTLEWELL HYPOTHESIZED that something in the industrial regions caused the darker peppered moths to be more successful than the lighter peppered moths. WHAT WAS IT? The darker peppered moths’ ability to blend into their habitat & avoid predation. Kettlewell called this Industrial Melanism. Melanin is a pigment in the moth’s body. Industry was releasing soot which covered the lichen, hence, Industrial Melanism. Darwin would have called this ? FITNESS!

Recap of Key Concepts The Process of Changing a Gene Pool in a Population Fish gene pool animation The Process of Evolution Explanation of definitions http://www.wadsworthmedia.com/biology/0495119814_starr/big_picture/ch16_bp.swf Wadsworth site http://glencoe.mcgraw-hill.com/sites/9834092339/student_view0/chapter20/animation_-_mechanisms_of_evolution.html

VI. POPULATION GENETICS Scientists study GENETIC TRAITS in populations over time Populations of the same species can breed because they share a GENE POOL the genetic makeup of members of a population. REMEMBER-genes come in two forms of alleles, dominant, and recessive. In a GENE POOL each allele represents a TRAIT

VII. What causes Development of a New Species? Two SPECIES can not occupy the same niche over a long period. Why? COMPETITION, change in habitat, may cause one to adapt or lose out & not survive Some SURVIVE & may REPRODUCE passing on their TRAITS • The GENE POOL may change due to differences caused by the ADAPTATION to the environment Example-mutation

THE PROCESS OF SPECIATION Process of speciation ADAPTIVE RADIATION-from one species can new ones evolve(common ancestry) A population of a species migrates from the original habitat & adapts to a new habitat, this is called -DIVERGENT EVOLUTION. Example beak size in finches of the Galapagos, types of food eaten on island. Convergent Evolution unrelated species live in similar environments indifferent parts of the world

The Grant’s study of finches on the Galapagos Video https://www.youtube.com/watch?v=l25MBq8T77w https://www.youtube.com/watch?v=mcM23M-CCog