Tiktaalik

1
Tiktaalik
Tiktaalik Discovered in 2004 on Ellesmere Island,
Canada.
Fossil dated to 385-359 million years ago
2
Archaeopteryx
Fossil dated to 150 Million years ago
3
Nostrils
Source evolution.berkeley.edu
4
(No Transcript)
5
Fossil beta globin
Scientists 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.
Looks like a broken down beta globin gene
Ice fish genome
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.
6
Human chromosome 2
Human chromosome 2
Looks like a centromere
centromeres
Chimp chromosomes 2q and 2p
Humans have 23 pairs of chromosomes. All other
ape species have 24 pairs.
7
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.

8
(No Transcript)
9
Guppy experiment 1
Initial observations Scientists observe that
male guppies that stand out from their
surroundings attract more females
evolution.berkeley.edu
10
Guppy experiment 2
evolution.berkeley.edu
11
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 1940s
• 95 of staph strains now resistant to penicillin
• Many strains are now resistant to multiple
  antibiotics penicillin, methicillin,
  tetracycline
• MRSA Methicillin-resistant Staphylococcus aureus

12
(No Transcript)
13
Nested traits
Nucleus Chloroplast Seeds Nervous system Jaws 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
14
Comparing DNA
Species Partial sequence of beta globin gene
Human ATGGTGCATCTGACTCCTGAGGAGAAGTCTGCCGTTACTGCCCTGTGG
Macaque ATGGTGCATCTGACTCCTGAGGAGAAGAATGCCGTCACCACCCTGTGG
Mouse ATGGTGCACCTGACTGATGCTGAGAAGGCTGCTGTCTCTGGCCTGTGG
Rat ATGGTGCACCTGACTGATGCTGAGAAGGCTGCTGTTAATGGCCTGTGG
Dog ATGGTGCATCTGACTGCTGAAGAGAAGAGTCTTATCTCCAGCATGTGG