what is a synapomorphy?. terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree...
TRANSCRIPT
![Page 1: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/1.jpg)
What is a synapomorphy?What is a synapomorphy?
![Page 2: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/2.jpg)
TermsTerms
systematics [taxonomy, phylogenetics]phylogeny/phylogenetic treecladogram tips, branches, nodeshomologyapomorphysynapomorhyautapomorphyplesiomorphysymplesiomorphyhomoplasyconvergencereversal of trait
systematics [taxonomy, phylogenetics]phylogeny/phylogenetic treecladogram tips, branches, nodeshomologyapomorphysynapomorhyautapomorphyplesiomorphysymplesiomorphyhomoplasyconvergencereversal of trait
monophyleticparaphyleticpolyphyletictree polarityoutgroupancestral groupsister groupcharacter congruencetopological congruencemaximum parsimony
monophyleticparaphyleticpolyphyletictree polarityoutgroupancestral groupsister groupcharacter congruencetopological congruencemaximum parsimony
PeoplePeopleWilli HennigWilli Hennig
![Page 3: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/3.jpg)
Principles of Phylogenetics:Tree Thinking
Wings
NoYes
![Page 4: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/4.jpg)
PHYLOGENETIC INFERENCE
Seeks to recover the historical genetic patterns of relationships among organisms
![Page 5: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/5.jpg)
PHYLOGENETIC INFERENCE
Principles: Assumes similar features are homologous until shown otherwise
![Page 6: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/6.jpg)
correspondence(morphological,molecular, behavioral)inherited through common ancestry
HOMOLOGY
![Page 7: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/7.jpg)
F&H Fig 2.1
Structural homologies
![Page 8: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/8.jpg)
PHYLOGENETIC INFERENCE
Assumes similar features are homologous until shown otherwise
Willi Hennig(1950s-1960s)
Principles:
Uses shared derived features, not shared ancestral ones (Hennig formalized this)
![Page 9: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/9.jpg)
synapomorphy
shared derived character
HomoAustralopithecus
Large braincases
![Page 10: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/10.jpg)
autapomorphy
uniquely characterderived
H. sapiensAustralopithecus
High forehead
![Page 11: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/11.jpg)
symplesiomorphycharacterancestral shared
HomoAustralopithecus
bipedal
![Page 12: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/12.jpg)
synapomorphy
shared derived character
autapomorphy
uniquely characterderived
symplesiomorphycharacterancestral shared
![Page 13: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/13.jpg)
PHYLOGENETIC INFERENCE
Uses shared derived features, not shared ancestral ones (Hennig formalized this)
Assumes similar features are homologous until shown otherwise
Treats shared derived features (character states) as markers of historical relatedness
Principles:
![Page 14: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/14.jpg)
PHYLOGENETIC INFERENCE
Uses shared derived features, not shared ancestral ones (Hennig formalized this)
Assumes similar features are homologous until shown otherwise
Treats shared derived features (character states) as markers of historical relatedness
Same basic logic used for comparative morphology or DNA
Principles:
![Page 15: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/15.jpg)
Tree-speak
node
tip
branch
branch
tip tiptip
![Page 16: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/16.jpg)
BUMBLE BEEexternal skeletonwings6 legshair“cold-blooded”
TANAGERinternal skeletonwings2 legsfeathers“warm-blooded”
TREE FROGinternal skeletonno wings4 legsno hair or feathers“cold-blooded”
OPOSSUMInternal skeletonno wings4 legshair“warm-blooded”
A simple example…..
![Page 17: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/17.jpg)
First taking one character at a time….
Skeleton
External Internal
Character
Character State Character State
(0) (1)
![Page 18: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/18.jpg)
First taking one character at a time….
Skeleton
External Internal
(0) (1)(1)(1)
![Page 19: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/19.jpg)
Wings
NoYes
But….
![Page 20: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/20.jpg)
bird wings are homologous to front legs of frogs andopossum.and NOT towings of bee
so…
![Page 21: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/21.jpg)
Wings
NoYes, but convergent
![Page 22: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/22.jpg)
But….Legs
2 4 6
![Page 23: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/23.jpg)
so…
bird wings are homologous to front legs of frogs andopossum.so birds have 4 legs!
![Page 24: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/24.jpg)
Legs
4 6
really….
![Page 25: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/25.jpg)
(actually bumble bees can be endothermic temporarily…)
metabolism
Poikilothermic(“cold-blooded”)
Endothermic(“warm-blooded”)
![Page 26: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/26.jpg)
Body covering
Just skin Feathers Hair
But….
![Page 27: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/27.jpg)
Hair
Is hair of opossum and bee really homologous?
We can test whether these groups share common ancestry using other characters….
![Page 28: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/28.jpg)
Skeleton
External Internal
Legs
4 6
Metabolism
Poikilothermic(“cold-blooded”)
Endothermic(“warm-blooded”)
Body covering
Just skin Feathers Hair
Character state trees
Wings
NoYes, but convergent
![Page 29: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/29.jpg)
How can we combine the information from different characters to infer an overall phylogeny?
Skeleton
External Internal
Wings
NoYes, but convergent
Legs
4 6
Metabolism
Poikilothermic(“cold-blooded”)
Endothermic(“warm-blooded”)
Body covering
Just skin Feathers Hair
![Page 30: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/30.jpg)
How can we combine the information from different characters to infer an overall phylogeny?
If for only a few characters with no conflict, you can do this in your head, but
Quantitative methods are now implemented by computer to do this!
![Page 31: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/31.jpg)
First, make up a [character x taxon] matrix,
converting ancestral states to 0’s and derived to 1’s or 2’s
Bumble bee
Tree frog
Tanager
Opossum
LegsSkeleton Wings Metabolism Covering
0 1 1 0 2
1 0 0 0 0
1 2 0 1 1
1 0 0 1 2
![Page 32: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/32.jpg)
How do we know which state of a character is the ancestral one and which is derived?
--Fossils may help show earlier appearance!
--Outgroup AnalysisStates found within a group and also in related groups (outgroups) are more likely to be ancestral than those found only within the group
![Page 33: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/33.jpg)
Poikilothermy is likely to be ancestral in frog/bird/mammal group
States found within a group and alsoin related groups (outgroups) are morelikely to be ancestral than those foundonly within the group (ingroup)
outgroup
ingroup
poikilothermicendothermic
![Page 34: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/34.jpg)
Bumble bee
Tree frog
Tanager
Opossum
LegsSkeleton Wings Metabolism Covering
0 1 1 0 2
1 0 0 0 0
1 2 0 1 1
1 0 0 1 2
![Page 35: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/35.jpg)
These are then “optimized” onto possible phylogenetic trees, and the tree that requires the fewest total changes of character stateis chosen as the most likely(basic parsimony analysis)
(It is also possible to make decisions among treesbased upon the likelihood of alternative changes, rather than simply the evolutionarily “shortest” tree (we’ll see this with molecular data)
![Page 36: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/36.jpg)
Using only the shared derived states….!
skeleton
1
wings
1
2
legs
1
metabolism
1
2
covering
21
Bumble bee
Tree frog
Tanager
Opossum
0 1 1 0 2
1 0 0 0 0
1 2 0 11
1 0 0 1 2
Skel Wing Leg Metab Cov
![Page 37: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/37.jpg)
How do we resolve differences in relationships implied by different characters (character state conflict)?
Metabolism
Poikilothermic(“cold-blooded”)
Endothermic(“warm-blooded”)
Body covering
Just skin Feathers Hair
![Page 38: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/38.jpg)
skeleton
1
wings
1
2
legs
1
metabolism
1
2
covering
2
This tree requires 8 steps, including an extra step (homoplasy) due to convergence in covering character
1
![Page 39: What is a synapomorphy?. Terms systematics [taxonomy, phylogenetics] phylogeny/phylogenetic tree cladogram tips, branches, nodes homology apomorphy synapomorhy](https://reader033.vdocuments.us/reader033/viewer/2022061610/56649f285503460f94c40664/html5/thumbnails/39.jpg)
CoverBumble bee
Tree frog
Tanager
Opossum
0 1 1 0 2
1 0 0 0 0
1 2 0 1 1
1 0 0 1 2
Skel Wing Leg Metab
Using only the shared derived states….!
11
2
1
1
21
2
8 steps
steps steps
How many steps or evolutionary changes result from mapping the different character states onto these two other tree topologies?
Using the principle of maximum parsimony, which tree would be selected as the more likely ?
(See next pg.)