Warmup: Open your lab book to the Kerosene Karl activity we did yesterday in class. Make a graph (in your lab book--after the questions is fine) with the percent (%) of each allele on the Y-axis and the generation number on the X-axis. You should have 2 lines One for C allele One for c allele Allele % 1 2 3 4 5 6 7 8 9 10 Generation

Natural Selection

Darwin Publishes 1836 – returns from Beagle voyage 1858 – receives short essay from Alfred Wallace 1859 – publishes ‘On the Origin of Species’ Proposed Natural Selection is how evolution occurs Evolution has worked over millions of years and continues today

Heritable Variation Variation exists in nature (some examples) Fruit size Milk production Speed Height Coloration

Artificial Selection Humans selecting and breeding organisms for useful traits Traits are part of the natural variation among the organism

Warmup Revisit Kerosene Karl Evolution is the change in the allele frequency of a population. Did evolution occur in the caterpillar population in Kerosene Karl? 2. Identify each of the following points from Kerosene Karl: Population has variations. Some variations are favorable More offspring are produced than survive Those that survive have favorable traits. A population will change over time.

Natural Selection Process that describes how evolution takes place in nature Struggle for Existence Survival of the Fittest Descent with Modification

1. Struggle for Existence Malthus High birth rates, shortage of basic needs = competition for resources Members of species compete for food, living space, other necessities Predators that are faster get more food Prey that are faster or camouflaged avoid being caught

2. Survival of the Fittest Fitness = Ability of an individual to survive AND reproduce how well suited an organism is to its environment Adaptation = inherited characteristic that increases an organisms chance of survival

2. Survival of the Fittest Well suited individuals survive and reproduce more successfully (high fitness) Individuals with traits not suited to environment die or have few offspring (low fitness) Evolution clip

How is each of these traits adaptive in nature?? Orangutan’s long arms Harmless flies that mimic the sound of an angry bee/wasp Butterflies of one species that resemble other poisonous butterflies An insect that looks like a leaf or a stick- camouflage An opossum playing dead Behavioral vs. physical adaptations http://animals.nationalgeographic.com/staticfiles/NGS/Shared/StaticFiles/animals/images/800/orangutan-traveling-forest.jpg 11

2. Survival of the Fittest Only certain individuals produce offspring for next generation Over time, natural selection changes the inherited characteristics of a population

SELECTION Individuals without advantageous traits die before reproducing. Individuals with advantageous traits survive to reproduce. Again, make note the labeling of the axes Frequency die without reproducing These individuals These individuals survive to reproduce Characteristic 13

Populations change, not individuals The “average” characteristic or other measure of the population changes over generations average, 1st gen. average, 2nd gen. average, 3rd gen. average, 50th gen. Frequency die without reproducing These individuals die without reproducing These individuals These individuals survive to reproduce Characteristic

3. Descent with Modification Each living species has descended – with changes – from other species over time All living organisms are related to one another Natural Selection produces organisms With different structures Occupy different habitats

HOMEWORK Read section 15-3 in your textbook Complete WS 15-3 up to “Evidence for Evolution” (#1-16)