Module 2 Flashcards
Natural selection
Adaptive microevolutionary process that works best when there’s large amounts of genetic variation
Phenotype
Physical attributes
Genotype
Genetic attributes
Qualitative trait
Has discrete, described characters e.g. color genes, blood types
Quantitative trait
Additive/subtractive combination of many genes that may be measured, a complex trait e.g. height, weight, size
Quantitative genetics
Linking phenotypes to genotypes using genetic basis of complex traits
Heritability
Population level parameter determining how much genetics is involved as opposed to environmental input for compelled traits, determines response to selection
When low, variance is due to environmental pressures and hard to change via selection. When high, little impact from environment and selection acts as the greatest force
Life history traits
Heritable traits that impact a species/population reproductive strategies
E.g. longevity, reproductive output, size
Stabilizing selection
Favors intermediate or average traits. Most frequent in non-fitness traits
E.g. Birth size
Directional selection
Selection that creates a directional shift b/w generations. Occurs due to specific advantage or disadvantage
E.g. rabbits and disease
Disruptive selection
Favors extremes, once selective pressure is removed population will return to a normal distribution
Clines
Balance b/w directional selection and migration. Common for morphological and quantitative traits
Clines is steep when migration is low and visa versa
E.g. koalas
Heterozygous advantage
Heterozygous has greatest fitness (over dominance)
Heterozygous disadvantage
Heterozygous least fit (outbreeding), under dominance
Mhc
Alerts immune system of foreign bodies
Under balancing selection for heterozygous
Tasmanian devils have reduced genetic diversity of mhc genes and tumors
Mc1r
Color pigmentation gene part of melanin pathway
Different color morphs as a result of sexual selection
E.g. pocket mice
Conservation genomics
Use of genomic techniques to solve problems in conservation biology
Basically factors in environment, selection, and gene expression unto genetics using loci under selection as well as neutral markers
Conservation genetics
Uses selectively neutral loci and may only infer biological activity from genetic info
Illumina
Shotgun sequencing that relies on parallel amplification resulting in 6000 gb data
PacBio
Single molecule sequencing resulting in long reads
Rad-Tag
Type of genetic sequencing that does not depend on reference genomes
Candidate gene approach
Identifying genes through comparative analysis or differential gene expression studies
Best when lots of prior data is available. Uses outlier test to find SNPs of candidate genes
GWAS unordered
Used for unknown candidate genes
Generates 1000-10000 SNPs genome wide randomly followed by outlier test to find non-neutral loci
Used to trace origin of fish in markets
Genomic island of divergence
The sea level is the upper level of expected neutral divergence while anything above is strongly selected for and the island size correlates with strength of selection
Occurs with GWAS approach
GWAS ordered
Used for unknown candidates with known locations . Can determine type of selection
Defining CUs
1) use different markers for ESUs (both types) and MUs (just neutral)
2) test adaptive variation using outlier tests
3) complement genomic data with ecological, phenotypic, end environmental data
Assisted gene flow
Increasing genetic variation/adaptive potential of populations through increased natural gene flow
E.g. travel corridors
Targeted gene flow
Increasing adaptive potential through increased gene flow, increased diversity of traits and related alleles from a particular axis of selection (selective breeding)
Considers adaptive potential in relation to changing environments
Genetic rescue
Increases genetic variation of small inbred pops by artificially introducing outside individuals
Last ditch effort that’s only occurred with 10-20 pops like the Florida panther
Introduction and establishment
1st phase of invasive species establishment. Most important phase because it determines colonization. Dependent on # of individuals and releases
Lag phase
2nd part of invasive establishment. Depends on genetic adaptation and demographic heterogeneity
Expansion and spread
Final stage of invasive colonization. Dependent on fecundity and generation interval that may produce additional founder events
Heterosis
When outbreeding leads to hybrid vigor
Areas of invasive species control
Physical, biological, and genetic
Wildlife forensics
The use of genetic technology to assist in wildlife management/crime
