Welcome ! Today our 2nd to last unit Evolution! - but first please dig out the Genetics review sheet.

Welcome ! Today we do a good imaging Lab on animal hands – please grab Both lab sheets and look them over.

Google image pic of animal and x ray Use Reid park zoo x rays for injured Animals – you will prob need to look up A pic of human skeleton – labeled. The Bone names are the same as ours.

Evolution – a theory that Explains how species change Over time. Theory – concept that has Been repeatedly tested and Used to make predictions

Evolution is still very Controversial today – many Other theories exist – Ex = Creationism – religions etc. This material represents Theory only and material On our regents exam. Some States have laws about this.

Fossil records – help to Explain history of life. The Earth is around 4.5 billion Years old. Charles Darwin – theory of Natural selection – said Evolution was controlled by Nature or the environment.

http://www.youtube.com/watch?v=GhHOjC4oxh8

Darwin – Natural Selection Evolution = theory, organisms Change over time, most change is caused by the Environment and nature.

Individuals that survive and Reproduce have favorable Traits or genes, and these Traits are passed on. Bad genes do not survive and do not reproduce.

Rock mouse https://www.youtube.com/watch?v=sjeSEngKGrg

Overproduction – species Tend to produce more Offspring than are needed, Thus competition arises and The best, strongest, best Genes survive and are Passed on = Survival of the Fittest.

Genetic variation may Produce some offspring with A new favorable trait that Helps it survive this is known As adaptive value. This trait is passed on = evolution

Galapagos DVD video

Peppered moth lab

US Eugenics https://www.youtube.com/watch?v=IaH0Ws8RtSc&index=119&list=FLv86ZP7JCXSSP3opJWTuxwg

Changes occur by mutations And genetic shuffling during Meiosis. Genetic changes are either Structural, functional or behavioral

Structural change = organism Evolves favorable new Structures. Ex. Polar bears Evolved extra fur on the Bottom of their feet.

Functional changes = are Molecular or biochemical Changes that effect how an Organism works. Behavioral changes = how An organism acts Ex – expressway crows ????

Patterns of change Changes are often related to Changes in the environment Species with short life spans And short reproduction Change quicker

Failure to adapt to a changing Environment will most likely Result in the death of the species. The rate of evolutionary change is most directly linked To changes in the environment

Animal hands lab

Rapid changes do occur in Organisms with short life Spans and many offspring. Ex.= many insects become Resistant to pesticides after A few generations

These fast reproducing Organisms have a lot more Chance of mutations occuring

Larger organisms that pro- -duce few offspring show Much less change over time

Extinction – occurs when an Entire species disappears, Usually due to environmental Changes.

Darwin did not have a Complete understanding of Genetics, he was unable to Explain evolutionary change Due to mutations and meiosis.

Summary - the environment Causes most evolution – over – Production causes survival of the Fittest – a good trait that is passed On has an ADAPTIVE VALUE Fast reproduction rate = more Mutations = more change-evolution