Lec 22: Phylogenic and Macroevolution Flashcards
What is important for speciation to occur?
Reproductive isolation, keeps species apart and lets it evolve it different directions.
What is taxonomy?
the theory and practice of classification and naming
What is Systematics?
The study of biodiversity and evolutionary relationships among organisms.
What are the parts of a phylogenic tree?
Out group
In group
Terminal nodes (Taxa)
Terminal branches
Internal branches
Internal nodes
What is a paraphyletic group?
It contains some but not all the species derived from the common ancestor
How are traits changed as species changed on a phylogenic tree?
More closer share more similar traits, while the ones further away have very few similar traits.
What is the difference between paraphyletic group and monophyletic group?
A paraphyletic group, are a taxon whose members are derived from two or more ancestral forms not common to all the members.
Monophyletic group: A single ancestor gave rise to all the species in that taxon and no other species
Why are monophyletic groups preferred?
Because they link taxon names to evolutionary history.
What are ancestral traits?
A trait shared with common ancestor
What are derived traits?
A trait that differs from an ancestral trait in lineages, derived traits are MORE important to determine how organisms are more closely related to each other.
What is a challenge of using derived trait to make a phylogenic tree?
There are two types of derived traits:
Homology: Similarity due to shared traits
Homoplasy: similarity in traits due to convergent evolution.
If there was more convergent evolution it would be hard to determine how a trait is related.
What is convergent evolution?
The independent evolution of structures that resemble one another and perform similar functional tasks due to shared ancestory
What is the idea of key evolution?
Origin of a novel trait result in adaptive radiation
Carriers of trait can exploit new resources and sets of habitat
Usually associated with rapid evolution diversification
This can result in higher speciation or lower extinction
