Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
55 Cards in this Set
- Front
- Back
Gradualism |
Constant evolutionary change through time |
|
Punctuated Equilibrium |
Short bursts of change. Fossil records favor punctuated |
|
Evolutionary-Developmental Biology (Evo-Devo) |
Integrates developmental biology, paleontology, and anatomy with molecular biology, and genetics. |
|
HOX Genes |
Genes that control development (more HOX genes = more complex organism) |
|
Gene duplications |
Create more HOX genes - Paralog |
|
Orthologs |
A homologous gene in separate species that share common ancestry |
|
Parolog |
Gene copies within same species |
|
Mutations that affect spatial/temporal expression in HOX genes |
-Turns regulatory genes for HOX genes on/off -Results: Changes in structures Existing structures not to form existing structures to form in new places
|
|
Allometric growth |
A change in the rate of growth of a feature relative to other features. -ex. giraffe necks/vertebrate |
|
Paedomorphosis |
Retention of juvenile/larval characteristics in adults |
|
Using orthologs to infer evolutionary relationships of structures |
Ex. eyes in animals (Pax6 in mice vs eyeless in flies) |
|
Examples of regulatory gene mutations that cause morphological change |
-Chicken & duck have webbed embryos · BMP4A = tissue to generate · Gremlin = protein to inhibit BMP4 expression -Ubx in arthropod appendages -Hox d11 expression in fish vs limb buds |
|
Monophyletic Group |
Ancestor and all its descendants; good |
|
Paraphyletic Group |
Group with common ancestor but only some if its descendants; bad (missing some) |
|
Polyphyletic Group |
Groups of species with different common ancestors; worst |
|
Polytomy Phylogentic tree |
More than 2 groups emerge from a node (star phylogeny) |
|
Adaptive radiation |
Appears in phylogenies as polytomy = rapid speciation |
|
Colonization Event -Adaptive radiation Mechanism
|
habitat unoccupied = colonization by competitors |
|
Morphological Innovation -Adaptive radiation Mechanism
|
Allows new resources to be exploited
|
|
Mass Extinction -Adaptive radiation Mechanism |
Remove major competitors = allows survivors to exploit resources previously unavailable |
|
Fossil record |
Total collection of fossils that have been discovered |
|
Fossil Advantages |
Provides direct evidence |
|
Habitat Bias -Fossil disadvantages |
Burrowing/soft body organisms = more fossils |
|
Taxonomic Bias -Fossil disadvantages |
Organisms with hard body = more fossils |
|
Temporal Bias -Fossil disadvantages |
Older organisms are recycled into geology |
|
Abundance Bias -Fossil disadvantages |
More numerous organisms = more fossils |
|
Organically Preserved fossil |
pollen, insects in amber |
|
Compressed fossil |
Carbon rich film |
|
Permineralized fossil |
Ex. petrified wood |
|
Cast fossil |
Bone, branch, shell |
|
Molecular Clock |
Uses neutral mutation to estimate divergence of lineage -Cons: Caveats: difference in mutation rate of species |
|
Cladistics |
Tool for estimating phylogeny -input from: morphology, biogeography, development, paleontology, molecular data |
|
Sympleisomorphy |
Trait shared with ancestor |
|
Synapomorphy |
Shared derived trait (no ancestor) |
|
Ingroup |
Clade that shares synapomorphy |
|
Outgroup |
Closest ancestor of ingroup (lacks synapomorphy) |
|
Homoplasies -Potential problems |
Traits that are not homologous -Causes: Covergent evolution (bat + bird wing), evolutionary reversal (loss of traits) |
|
Maximum Parsimony |
The simplest explianation is the right one |
|
Phylogenetic Inference |
Uses phylogenies to understand evolutionary history and proccesses |
|
Hadean Eon |
formation of earth, primordial soup |
|
Archaen Eon |
origin of life, radition of prokaryotes |
|
Proterozoic Eon |
radiation of Eukaryotes |
|
Phanerozoic Eon |
radiation and diversification of multicellular organisms |
|
Cambrian Explosion |
rapid appearance/diversification of phyla |
|
Paleozoic Era |
Cambrian explosion first vertebrates invasion of land first amphibians, reptiles, insects, |
|
Mesozoic Era |
first dinosaur gymnosperms radiate first flowering plants
|
|
Cenozoic Era |
radiation of flowering plants/insects mammals, hominids
|
|
Mass Extinction |
60% species lost |
|
Permian Extinction |
90-95% marine taxa lost Causes: rapid climate shift, massive volcanic eruptions |
|
Cretaceous Extinction |
85% species lost... mainly dinasours cause: meteor |
|
Allopatric Speciation |
population become geopgraphically isolated
|
|
Dispersal/Colonization -Allopatric |
Small number of individuals disperses to a new habitat
|
|
Vicarriance -Allopatric |
large population split in two |
|
Sympatric Speciation |
Speciation without geographic isolation -natural selection overwhelms gene flow
|
|
Mechanisms that reduce gene flow |
Spatial, temporal, behavioral, polyploidy |