Macroevolution 1 Flashcards
Why do we use DNA?
Allows you to calibrate things in time (see how nucleotide fractions have changed)
Used for extant taxi (still living). The DNA defines species with recent common ancestor. DNA has thousands of characteristics therefore can overcome convergent.
Describe how fossils are formed by petrification (4)
- Death in water
- Sediment on top
- Pressure forms
- Eventually sees bone structures or carbon structures (eg leaves)
What does amber tar do?
Preserves 3D structure
What happens with the radioisotope C12/C14?
Decays over time from C14 to C12
If C14 decays by half etc you can measure the age
What does anatomy reveal?
Movement and speed
What do teeth show?
Diet
What does brainsize show?
Cognition
Why can’t we detect mammals in tar?
Because that has to be in water
What does the amount of preservation show?
If it was dry and cold (would make it well preserved)
How is DNA extracted?
- DNA fragmented
- But can use massive parallel sequencing to obtain deep reads
- Against a modern scaffold
Give an example of taking things from others in history.
Colonial history says Columbus discovered USA but people were already there.
Facts about Neanderthals? (3)
Share mutations with homeosapiens
Pale skin and red hair
Near complete genomes
Pros of de-extinction
Intellectual excitement
Bring back species
Ingrate extinction crisis
Cons of de-extinction (4)
Play god
Deflect conservation efforts
Stop us caring about vulnerable species
Welfare for organisms uncertain
What is de-extinction?
Bring extinct animals back to life
Use synthetic bio and take important bits of sequence to transfer into extant relative
