Learning Objectives: (from your notes and the packet) What are 4 general types of evidence that life changes over time? Fossil Record Evidence Comparative Anatomy Evidence Embryological Evidence Biochemical Evidence Know specific examples for all 4 types

Evidence Packet: 1)Law of Superposition: In most cases the fossils found deeper in the ground are older than the fossils found nearer the surface (a relative dating system) Fossils can be in the form of imprints, molds, casts, petrified remains, preserved in amber and even frozen in ice -Coal & Oil are organic Fossil of a sort -Half-Life gives confirmation of the major trends of earth’s timeline supporting the general idea of increasing complexity in the forms and variety of living creatures

2. Comparative Anatomy: Homologous structures- structures of different species that have the same evolutionary origins: but can have very different functions. Ex: bone structure of animal appendages

Of course sometimes the functions of the structure can be similar… very similar (thus so can the shape of the structures)

2. Comparative Anatomy: Analogous structures- similar functioning parts of different species that have the different evolutionary origins: but function in to perform similar tasks

Ex: Ear Muscles, 3rd eyelid, 2. Comparative Anatomy: Vestigial structure- organs/structures that serve no useful function but resemble functional organs in other species Ex: Ear Muscles, 3rd eyelid,

Darwin’s Tubercle: 10% of people have them

3) Comparative Embryology (embryos) Many Animals have similar characteristics as embryos: Fish, Reptiles, Birds, Mammals all have gill slits and a tail in the early stages of life

http://www.pbs.org/wgbh/nova/evolution/guess-embryo.html

4. Comparative Biochemistry: These are just a few examples -ATP-same functions (as a source of energy) in all living cells of nearly all species -DNA/RNA-all cells pass down information (genes-genetic instructions) from parent to offspring by using one of these molecules (mostly DNA) Many genes, compared between species, are so similar that often they can perform the exact same function even if placed in a different species….

Insect (compound) Eye Mammalian Eye

PAX-6: a gene that triggers eye development in mice (and works just as well in in all mammals and even some insects with compound eyes)

PAX-6: a gene that triggers eye development in mice (and works just as well in mammals and even some insects with compound eyes)

Reproductive Isolation Geographic Isolation Behavioral Isolation Temporal Isolation SPECIATION SPECIATION: Species ‘A’ Species ‘B’ Common Ancestor

Evidence For Evolution by Natural Selection Evidence Darwin did NOT Know: Evidence Darwin Knew: Fossil Record: shows extinctions and that species changed over long time, he also knew about the Law of Superposition Fossil Record: he knew nothing about half-life (λ) or how to tell how old the earth really is or exact age of fossils Embryology: he knew that certain features in embryos were not in the adults (ex legs in snakes) Comparative Biochemistry: knew nothing about DNA or genes or proteins or ATP (only knew parents looked similar to kids) Comparative Anatomy: knew of vestigial organs in creatures and of homologous and analogous structures How speciation worked: did not know of need for reproductive isolation to make new species, only that the environment pushed the ‘better’ adaptations to help survival and reproduction Artificial Selection: he knew how people selected for different dogs, horses, pigs, and farm plants