Lecture 6: Evolution, Genes, and Ecology Flashcards
Mutations that arise in what regions of the DNA are often eliminated by Natural selection?
noncoding
If mutations accumulate in noncoding regions at a constant rate, differences in the DNA sequences can serve as what?
a molecular clock
What does a molecular clock do?
It indexes the time at which two species diverged
Large difference imply divergence in the distant ____
past
Small differences in DNA sequences imply a more _____ common ancestor
recent
How are molecular clocks calibrated?
The fossil record and biogeographically with independent data
Phylogenies can help reveal what type of convergence?
Homoplastic
Similar traits have evolved independently in different ____
clades
What can phylogenies illuminate?
The stepwise evolution of complex characters
How do the initial stages of a character evolve?
as an adaptation to some environmental selective pressure
How can we map character transitions onto phylogenies?
using the principal of parsimony
What was used to understand how COVID- 19 spread?
phylogenetic analysis
What did the phylogenetic analysis of COVID-19 show?
that there were at least 9 introductions of the strains
What eon and around what year was the formation of the earth and moon?
The Hadean eon and around 4.5 BYA
What were the eras in the Archean Eon?
- Eqarchean
- Paleoarchean
- Meoarchean
- Neoarchean
What era and eon did prokaryotes appear?
The paleoarchean era in the Archean eon
What era and eon was the oldest fossil found and what was it?
It was in the paleoarchean era in the archean eon and it was a stromalites
What era and eon did the appearance of eukaryotes occur?
The neoarchean era in the archean eon
What eras are in the Proterozoic eon?
Paleoproterozoic
mezoproterozoic
neoproterozoic
When was the first multicellular life found, name the era and eon?
The Neoproterozoic era in the proterozoic eon
What eras are in the phanerozoic eon?
- Paleozoic
- Mesozoic
- Cenozoic
What periods are in the Paleozoic era?
- cambrian
- Ordovician
- Silurian
- Devonian
- Carboniferous
- Permian
What happened in the cambrian period?
The first true vertebrates appear
What happened in the ordovician period, and what era is it part of ?
Plants began to colonize land and it is in the palezoic