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;
42 Cards in this Set
- Front
- Back
Hybrids
|
Results when isolated populations reconnect and produce viable offspring
|
|
Hybrid Zones
|
Areas of overlap where interbreeding of separate species occurs. The viability of the hybrid increases the hybrid zone
|
|
Gradualism
|
Genetic change is continuous and it slowly accumulates through time. Lots of transitional forms
|
|
Punctuated Equilibrum
|
Change in genetics occurs in short bursts. There exists long periods of little genetic change. Predicts that new species will appear rapidly
|
|
Fossil Records support?
|
Punctuated Equilibrum
|
|
Molecular Data supports?
|
Gradualism
|
|
Evolutionary-Developmental biology
|
where paleontology, anatomy, developmental biology, molecular biology, and genetics attempt to explain rapid development of new body plans
|
|
Hox Genes
|
Specific genes the regulate body development. Acts like a switch board to turn genes on and off. Hox genes are controlled by other regulatory genes
|
|
Cambrian Explosion
|
Major radiation of multicellular animals at the beginning of the paleozoic era. Almost every modern phyla appears during this time.
|
|
Hox Genes Continued
|
More Hox genes = more complex body. Gene duplication mutations produce more Hox genes (paralog)
|
|
Mutations and Hox Genes
|
Can cause changes in body structure. Ex: Ubx gene causes wings to grow in different thoracic segments on insects
|
|
Orthologs
|
Arise from developmental and molecular evolution
|
|
Paralogs
|
A result of gene duplication
|
|
Regulatory Gene mutation examples
|
Gremlin gene in chickens and ducks for webbed feet. Ubx in insect wings. D11 expression in fish vs. limb buds
|
|
Allometric Growth
|
differences in growth rates. Ex: chimp vs. human skull growth
|
|
Paedomorphosis
|
Retention of juvenile characteristics in adults. Ex: copepod crustaceans
|
|
Orthologs continued
|
Eyeless genes in flies and Pax6 gene in mice. Transplant of pax6 gene into a fly caused eye growth
|
|
Phylogenies
|
An evolutionary history for a group of organism.
|
|
Branch
|
Populations through time
|
|
Node
|
Diverged lineage
|
|
Tip
|
extinct or still living species
|
|
Root
|
Common ancestor of all organisms in the tree
|
|
Polytomy
|
more than 2 groups emerge from a node
|
|
Sister Taxa
|
Groups that occupy adjacent branches linked by a node
|
|
Outgroup
|
Taxon that diverged prior to a most ancient node of a tree
|
|
Ingroup
|
Clade taxa that are the closest related
|
|
Monophylenetic
|
Ancestor and all of the descendants (good)
|
|
Polypheletic
|
Group of species with different common ancestors (bad)
|
|
Paraphyletic Group
|
group with common ancestors, but only some of its descendants (bad)
|
|
Adaptive Radiations
|
Represents a period of rapid speciation. Colonization, morphological innovation, and mass extinctions
|
|
Colonization
|
Habitat unoccupied by competitors is colonized by a species. Ex: Hawaiian islands and rose finches
|
|
Morphological Innovation
|
New innovations all for new resources to be exploited. Ex: Flowers, feathers, mouth part modifications.
|
|
Tools used to create phylogenies
|
Fossil Records
Molecular Biology (DNA) Anatomy/embryology |
|
Fossils
|
Physical trace of an organism that lived in the past.Organically preserved in amber, compressed carbon film, casts, permineralization
|
|
Fossil Limitations
|
Habitat Bias, Taxonomic flaw, temporal bias, abundance bias
|
|
Habitat bias
|
Burrowing organisms and soft bottom organisms more likely to make fossils
|
|
Taxonomic Flaw with Fossils
|
Organisms with hard parts more likely to leave fossils that soft animals like sponges and slugs
|
|
Temporal Bias
|
Older organisms less likely to leave fossils
|
|
Abundance Bias
|
More numerous organisms are more likely to leave fossils
|
|
Molecular Clock
|
Neutral mutations are used to estimate the time of divergence for lineages. In non-coding DNA
|
|
Flaws with the Molecular Clock
|
Some species have very quick generatoins. Mutations can be affected by the environment. Species mutate at different rates. Reverse mutations are possible
|
|
Examples of using the Molecular Clock
|
Short term analysis-introns of mitochondrial DNA. High rate of change.
Long Term Analysis-Short subunit of RNA. Slowly changes, conserved pieces of DNA |