1 Tiktaalik Discovered in 2004 on Ellesmere Island, Canada. Fossil dated to 385 - 359 million years...

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Tiktaalik

TiktaalikDiscovered in 2004 on Ellesmere Island, Canada.

Fossil dated to 385-359 million years ago

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Archaeopteryx

Fossil dated to 150 Million years ago

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Nostrils

Source: evolution.berkeley.edu

“Fossil” beta globinScientists have discovered that The Antarctic Ice Fish (Chaenocephalus aceratus) does not have any red blood cells. Instead of transporting oxygen through their blood, they absorb oxygen from the water through their skin and large gills.

It is discovered that the ice fish genome contains a segment that looks like the beta globin gene found in closely-related fish, but is not functional.

Ice fish genome

Looks like a broken down beta globin gene

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Human chromosome 2

Human chromosome 2

Chimp chromosomes 2q and 2p

Looks like a centromere

Humans have 23 pairs of chromosomes. All other ape species have 24 pairs.

centromeres

Vestigial parts• Humans have much smaller appendices than herbivorous animals. • In herbivorous animals, but not in humans, the appendix serves to aid digestion of plant material. • It is still unclear what function, if any, the appendix serves in humans.

• Humans have a small immobile tail made up of four fused vertebrae.• In other primates, these vertebrae are not fused and allow the tail to move, aiding in balance and mobility.

Guppy experiment #1

Initial observations: Scientists observe that male guppies that stand out from their surroundings attract more females

evolution.berkeley.edu

Guppy experiment #2

evolution.berkeley.edu

Staphylococcus aureus

• Bacteria commonly found on mucous membranes and skin

• Can cause infections (Staph infections)• Penicillin introduced as antibiotic in 1940– very effective against Staph in the early 1940’s

• 95% of staph strains now resistant to penicillin• Many strains are now resistant to multiple

antibiotics: penicillin, methicillin, tetracycline– MRSA: Methicillin-resistant Staphylococcus aureus

Nested traitsNucleus Chloroplast Seeds Nervous

systemJaws Placenta Feathers

Bacteria

Algae X X

Corn X X X

Palm Tree X X X

Jellyfish X

Starfish X X

Human X X X X

Cow X X X X

Crocodile X X X

Robin X X X X

Cardinal X X X X

Comparing DNA

Species Partial sequence of beta globin gene

Human ATGGTGCATCTGACTCCTGAGGAGAAGTCTGCCGTTACTGCCCTGTGG

Macaque ATGGTGCATCTGACTCCTGAGGAGAAGAATGCCGTCACCACCCTGTGG

Mouse ATGGTGCACCTGACTGATGCTGAGAAGGCTGCTGTCTCTGGCCTGTGG

Rat ATGGTGCACCTGACTGATGCTGAGAAGGCTGCTGTTAATGGCCTGTGG

Dog ATGGTGCATCTGACTGCTGAAGAGAAGAGTCTTATCTCCAGCATGTGG

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