26 - Phylogenetics - Using Trees Flashcards
1
Q
What is a gene tree?
A
- within phylogenetic trees
- shows the spread of different alleles
2
Q
What are the possible outcomes of hybridisation?
A
- nothing - offspring infertile or unfit
- forms hybrid zones - specific areas of hybridisation
- exchanges a few genes - introgression
- form a new hybrid species
3
Q
What is allopolyploid speciation?
A
- hybridisation of two species
- keeps both copies of gametes
- increase in ploidy
4
Q
What is homoploid hybrid speciation?
A
- Where there is no genome duplication
- F1 hybrid has incompatibilities but is still fit enough
- BDMIs selected against in future generations
- only compatible combinations remain
5
Q
What is incomplete lineage sorting
A
- just because 2 species share the same allele, does not mean they are the closest related
6
Q
What is a monophyletic clade?
A
includes and most recent common ancestor and all of its dependents
7
Q
What is a polyphyletic clade?
A
does not include the common ancestors
8
Q
What is a paraphyletic clade?
A
Most recent common ancestor but not all of its decendents
9
Q
What is the effect of Neanderthal integression on toll-like receptors?
A
- increases their expression
- associated with an increase in allergies
