Lecture 9 - fossils and the molecular revolution Flashcards
what biological advance was made in the 1900’s?
mendel’s work was rediscovered and theory of heredity was integrated into darwinian evolutionary theory to create neo-darwinian evolution
what biological advance was made in the 1920’s - 30’s?
neo-darwininian evolution hardened into the modern synthesis as mathematics of gene frequencies are explored
1960’s?
genetic code established
1970’s?
technological innovation enables manual DNA sequencing
1980’s?
identification of genes and gene function
2000’s?
whole genome sequencing and evo-devo research intensifies
amber fossils:
- quick preservation
- actively removes water and air
- stops DNA breaking down due to the presence of oxygen and water
- allows preservation of DNA
is the mammoth more closely related to the asian or african elephant?
asian - diverged 6-7 million years ago
what 3 things has the developments in molecular biology helped us to do?
- Molecular taxonomy - improved phylogenetic analysis as can create massive databases of molecular characters
- Molecular biogeography - sequence people from different parts of the world and analyse genetic differences - hugely supports out of africa model
- Molecular clocks
what is a molecular clock?
a technique that uses the mutation rates of biomolecules to deduce the time in prehistory when 2 or more life forms diverged
what dominated the skies within the cretaceous?
pterosaurs
* meant birds were not diverse or common in early cretaceous
Neognathae
the majority of living birds, 8,500 species within 140 families
what does developmental genetics allow us to do?
- look at how evolution works
- understand the nature, speed and effects of genome evolution
what is evo devo?
informal term for evolutionary development
what does evo devo allow us to do?
identify genes and gene functions which can then establish their distribution among living organisms and decipher where they evolved on a phylogeny
*fossil record enables us to date these events
