Evidence of Evolution Fossil Record Anatomy Embryology

Evidence of Evolution p106  Warm up: what does “Descent with modification“ mean?  Adaptations- traits that are used by an organism to survive in a particular environment. 1.Mimicry- looking like something else 2.Camouflage-blending into environment 3.Developing physiological immunity- clownfish and anemone.

mimicrymimicry video

Fossils p106  Evidence of an organism that lived long ago and shows organisms changing over time.

Extinct Camel Camelops hesternus  The western camel had a very similar build to the living bactrian (two- humped) camel, but was slightly taller (standing seven feet at the shoulder). The western camel was more closely related to the llama than to living camels.

Homology p106 Homologous structures: parts of organisms that are similar in structure and or function. Ex. Forelimbs of animals

Inheriting homologies

Adaptations for Survival p105  Minilab 15.1 p398  Answer #1-3

Analogous Structures p108  Warm up: give some evidence for evolution.  Do not have a common ancestor but are similar in function.  Structures are similar in function among species.  Streamlined body shape and pectoral fin/flipper  Wings of insect and wings of a bird

Analogous North and South America (placental mammals) vs. Australia (marsupials) Traits in each pair analogous but not homologous

How do analogies evolve?  u/evolibrary/article/0_0_0/s imilarity_hs_08 u/evolibrary/article/0_0_0/s imilarity_hs_08

Vestigial Structure p108  A body structure that has no function in present-day organism but was probably useful to an ancestor.

Transitional whales (Artiodactyla): from land to deep sea Rhodocetus spp. Ambulocetus natans Fig 2.8 Transition fossils (evidence of ancestry and evolution of vestigial limbs)

Embroyology p108  Embryo – earliest stage of growth and development of plants and animals

Embryology p108  embryos of different species look similar, suggesting evolution from a distant, common ancestor. The embryos are extremely similar!

Biochemistry p108  Nearly all organisms share same biochemicals: DNA, ATP, enzymes.  Comparing the DNA or RNA of different species shows how closely related they are.  Ex: our DNA is 98% the same as chimpanzees. Share a very recent common ancestor. videovideo

Pleistocene La Brea Tar Pits  Late Pleistocene animals La Brea, California Saber-tooth Cats Giant Ground Sloth

Shasta Ground Sloth Harlan's Ground Sloth Extinct Ground Sloths of Nevada and S. California

Gypsum Cave, Clark Co., Nevada (Frenchman Mtn) occupied by Pleistocene mammals Ground sloth bones and dung Camel and Horse bones Paleoindian Bone flute

Fig 2.8 Transition fossils (evidence of ancestry and evolution of vestigial limbs)

Fig 2.18 Change thru time- Fossil Record Sequential order of origin- Extinction

Fig 2.18 Change thru time- Fossil Record Sequential order of origin Extinction

Dating of Fossils  Relative Dating: Like stacking newspapers at home, the oldest is at the bottom, the youngest at the top.  Radiometric dating: Use isotopes to obtain the accurate dates of fossils