Do Now

1. What is biogeography?

2. Why do distantly related species in very different places sometimes share similar traits?

Study of where organisms live now and where they and their ancestors lived in the past.

Biogeographical patterns• Closely related species

differentiate in slightly different climates.

• Very distantly related species develop similarities in similar environments.

Homework and Announcements

Read/Notes 26.3 and pages 902-903Typed Lab Report: turnitin.comUSA TestPrep

Title: Evidence of Evolution – 16.4

How does the geographic distribution of species today relate to their evolutionary history?

How do fossils help to document the descent of modern species from ancient ancestors?

What do homologous structures and similarities in embryonic development suggest about the process of evolutionary change?

How can molecular biology be used to trace the process of evolution?

What does recent research on the Galapagos finches show about natural selection?

SWBAT describe evidence of evolution.

Brain Pop – Charles Darwin

Evidence of EvolutionDarwin hypothesized that animals

evolved because of natural selection… what is that??

BiogeographyPatterns in the distribution of living

and fossil species tell us how modern organisms evolved from their ancestors.

BiogeographyClosely related but different

Distantly related but similar

Alike species with different traits

Different species with same traits (similar environment)

Age of Earth & Fossils

Radioactive data shows Earth to be 4.5 billion years old – supporting Darwin’s theory (lots of time for evolution)

Recent fossil records are filling the gaps, showing that modern species evolved from extinct ancestors.

Comparing Anatomy & EmbryologyEvolutionary theory explains the existence

of homologous structures adapted to different purposes as the result of descent with modification from a common ancestor.

Comparing Anatomy & Physiology

Homologous Analogous

Similar structure Similar function

Comparing Anatomy & EmbryologyVestigial structures aren’t necessary,

but don’t harm the function of the organism and so they remain

Example: Appendix!

Comparing Anatomy & EmbryologySimilar patterns of embryological

development provide further evidence that organisms have descended from a common ancestor.

Genetics & Molecular BiologyAt the molecular level, the universal

genetic code and homologous molecules provide evidence of common descent

Most of the DNA and RNA used from bacteria to humans is the same. We must have come from a common ancestor!

Genetics & Molecular BiologyHomologous proteins are shared from

bacteria to humans – how we make insulin from bacteria for our use.

Homologous genes exist between flies and humans – these same genes direct our head-to-tail development and limbs

Testing Natural SelectionThe Grant’s were able to test Darwin’s

hypothesis by:Analyze that there was enough heritable

variation in the traits for natural selectionThere were enough differences in beak size

and shape to produce differences in fitness

Testing Natural SelectionDry weather = more survival of large beak

birdsTheir data confirmed that competition and

environment drive natural selection

Laughter is an adaptation?PBS What makes us Human NOVA Science

NOWEvolution of Laughter

Class Data Chart- Opposable thumb Texting

Groups With ThumbAverage Time in seconds

Without ThumbAverage Time in seconds

Group 1

Group 2

Group 3

Group 4

Group 5

Group 6

Hi my name is Bob and I like to use my thumbs.

Graphing – Remember TAILS

Group 1 Group 2 Group 3 Group 4 Group 5 Group 60

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Opposable Thumb Texting

Texting With Thumb Texting Without Thumb

Tim

e in s

eco

nds

Y

X

Independent WorkRead/Notes 26.3 and pages 902-903Typed Lab Report: turnitin.comUSA TestPrep