Wednesday May 3rd

Overarching Essential Questions:What role does data play in discovering new ideas in natural selection and evolution?

Natural Selection/ Adaptation/ Evolution Essential Questions:What ties all current life on Earth to single-celled organisms that evolved billions of years ago?How has life on earth changed throughout time?

Vocabulary: Relative Dating Radioactive DatingEntry Task: Get out Vocabulary Packets and

Science Note books

Conclusion: Essential Questions Reflection (5)

Assignments:Opposable Thumb Lab (5/4)Evidence of evolution (5/4)Relative Dating Lab (5/4)Frayer Model Vocab pkt (5/12)

Homework: Homework Weekly Packet #1 (5/4)Homework Weekly Packet #2(5/12)

Plan for Today:

• Quiz

• Notes on Common Descent

evidence

• Videos built in

• Relative Dating Lab

Five Main Types of Evidence For Common Descent

1. Fossils

2. Homologous structures

3. Similar embryo development

4. Biochemical evidence

5. Geographical distribution

Fossil Record• Fossils are evolutionary evidence

• Fossils show that ancient species share similarities with species that now live on Earth.

• Fossils records provide evidence that living things have changed over time.

Glyptodont Armadillo

Fossil layers show change over time.

Fossil layers show change over time.

Compaitive Anatomy• Analogous structures

• Homologous structures

• Vestigial structures

Analogous Structures

• Structures that do not have a common evolutionary origin but are similar in function.

• Shows that functionally similar features can evolve independently of each other

• Ex: wing of an insect and wing of bird

Analogous Structures

Homologous structures Video

• Anatomically similar structures inherited from a common ancestor

• These structures can be similar in arrangement but different in function.

Vestigial Structures Video

• A body structure that has no function in a present-day organism but was probably useful to an ancestor.

• This shows a change over time

Comparing Embryos

• Embryo: the earliest stage of growth and development of both plants and animals

• Vertebrate embryos exhibit homologous structures during certain phases of development but become totally different structures in the adult forms.

Comparing Embryos

• Similar embryo development may suggest a common ancestor

Biochemical Evidence

• Common ancestry can be seen in the complex metabolic molecules that many different organisms share.

• Comparison of the DNA or RNA of different species produce biochemical evidence for evolution

Biochemical Evidence

• Comparisons of the similarities in amino acids and other molecules across species reflect evolutionary patterns seen in comparative anatomy and in the fossil record.

Geological Distribution

• Similar animals are found in different locations around the world.

• Animals ended up evolving similar features for their environment because of their location on earth

• They look the same but live in different areas

Vocab Word 13: Relative Dating● By comparing rocks from one area to another, scientists can find the

relative age of the samples:

o One is "older" and the other is "younger."

● Fossils contained in these layers can also show what life existed on Earth at the same time.

o History can be read from the bottom to the top.

• Relative dating estimates the time during which an organism lived.

• It compares the placement of fossils in layers of rock.

• Scientists infer the order in which species existed.

Vocab Word 14: Radioactive DatingRadiometric dating uses the natural radioactivity of rocks to determine their absolute age.

• Radioactivity

• release of high-energy particles from unstable atoms,

• Radioactive isotope- an isotope that undergoes radioactive decay

• - used to determine absolute age EX. Uranium 238 and Carbon 14

• Uranium - 238 Radioactive Isotope Carbon 14 Radioactive Isotope

Half – life Radioactive Decay over 4.5 Billion years Half life 5,700 year

● Lead-206 Stable Isotope Nitrogen 14 Stable Isotope