3.1 Flashcards
What does phylogeny describe?
The evolutionary history of relationships among organisms
How is phylogeny used?
Classify organisms into evolutionarily related groups
True or false: The phylogenetic tree of life shows evolutionary relationships among different groups of organisms
True
Wings and echolocation evolvved at the same time in bats. What are they?
Correlated traits
Wings evolved independently in birds and bats, and were not present in their common ancestor. What are they?
Convergent traits
What kind of evidence constructs phylogenies?
Molecular data, amino acids, DNA, and RNA sequencing all show evolutionary history. Morphology, fossil records, and development are also evidence
What do phylogeny and speciation have in common?
Phylogeny shows the speciation process
What are sister groups?
Two groups that are each other’s closest relative
True or false: Species at the top of a tree are more evolved that other lineages
False, they are not better simple because they developed earlier, additionally the order can be changed
Can lineages be rotated around nodes? Does the vertical order matter?
Lineages can be rotated, order does not matter
“Species that branch off early on the tree of life evolved into other species and are more primitive” What is incorrect about the statement?
They did not evolve, they are just cousin species. Analogy: Two twins grow up identical, but both get married and have kids. The kids of the twins did not become another species or become different in anyway that is not genetic, the are simply cousins
What are three ways phylogenetic trees can be drawn?
Bottom to top, in a circle, or left to right
What are monophyletic groups also called?
Clades or lineages
Which group reflects evolutionary RELATIONSHIPS?
Monophyletic groups
What is a monophyletic group?
Includes all descendants of a common ancestor. A way to test this is by the snip test, if you cut a line in a tree would the detached part include all the descendants of the ancestor?
Are clades one simple thing?
No, they are nested and can be within each other
What are taxonomic categories?
Groups defined by clades
How are organisms classified into clades?
Ancestral and derived traits that are shared
What is an ancestral/basal trait and what is another name for it?
A characteristic that was present in the ancestor, also know as plesiomorphies
What is a derived trait and what is another name for it?
A characteristic that is different from the ancestral trait, also known as apomorphies
What are synapomorphies?
Derived traits shared between groups of organisms.
What is the principle of Parsimony?
Trees with the fewest number of evolutionary changes are preferred
What can interrupt the principle of parsimony?
Additional data is uncovered to support the alternate phylogeny
What are the three domains of life?
Bacteria, Archaea, and Eukarya
