BIOL 3130 Lecture Notes - Lecture 3: Conservation Genetics, Tandem Repeat, Genetic Drift
Conservation genetics encompasses genetic management of small
populations, resolution of taxonomic uncertainties and management units, and
the use of molecular genetic analyses in forensics and to understanding
species' biology (2003)
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Conservation genetics encompasses the use of genetic theory and techniques
to reduce the risk of extinction in threatened species (2010)
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Conservation genetics is an interdisciplinary subfield of population
genetics that aims to understand the dynamics of genes in populations
principally to avoid extinction. Therefore, it applies genetic methods to
the conservation and restoration of biodiversity (2017)
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Conservation genetics is an interdisciplinary science that aims to apply
genetic methods to the conservation and restoration of biodiversity (2013)
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What is conservation genetics?
How much genetic variation is available in endangered and threatened species
for adaption to future environmental change?
1.
How do genetic factors (random genetic drift, inbreeding depression and
mutation) directly affect current population viability and extinction risk?
2.
What is the unit or group to be conserved?
3.
Three Categories of Conservation Genetics Questions:
"….population genetics and population dynamics problems faced by a population at
risk of extinction because its numbers are small and those numbers are capped."
(Graeme Caughley 1994)
Thomson Reuters…
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Meta-analysis of concepts, methodologies, and taxa in Conservation Genetics
Tandem repeats of short DNA sequences = slight length variation
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Estimates heterozygosity in presumably neutral loci
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Hard to design for more than one species
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Microsatellites
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Mitochondrial DNA
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Techniques of Conservation Genetics:
Europe > NA > Australia > Africa > Asia > SA > Antarctica > Central
America
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Microsatellites > mDNA > ….
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Publications:
Measured by concept, methodology, or taxa, the publications are directed
towards sub-specific problems
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However, these problem are only tractable when you know what the 'it' is
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….
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Conservation Genetics:
"Stated bluntly, unless species are known to science and recognized by scientists, no
appreciable progress is possible in basic or applied biology"
Issues currently obstructing progress in taxonomy
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Lacking the taxonomic expertise to adequately describe biodiversity on
the planet
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To increase our base taxonomic expertise to handle to biodiversity that
exists yet to be described
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To get those already trained as taxonomists to publish their findings
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Canada's constrained capacity to analyze biodiversity information
impedes the nation's ability to achieve the goals set out in these policy
instruments
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This stagnation constrains Canadian research scientists, biasing…
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The "taxonomic impediment"
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"no one definition has yet satisfied all naturalists' yet every naturalist
knows vaguely what he means when he speaks of a species" (Darwin)
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"groups of actually or potentially interbeeding natural populations
which are reproductively isolated from other such groups"
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"…what a good taxonomists says"
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A species is…
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Definitions (being and reality)
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What precisely is a species (ontology)
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Concepts (what we might know)
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What precisely is in a species (epistemology)
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"Species problem"
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However, the "species" problem is plagued by two problems:
Four unique states
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Over 600 positions
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DNA-based identification system (DNA barcoding)
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DNA barcode acts as a standardised word
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DNA barcodes are known for 12.7% expected animal diversity
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Genomes known only for .015% of described animal species
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An Epistemology Tool:
How many species of giraffe --> 6-11
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Forest vs. Savannah
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How many species of African Elephants --> 2 (potentially 3)
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How many species of orca --> 5+
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DNA barcodes can be used to prevent poaching
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What can DNA barcodes do for conservation?
Most are invertebrates (arthropods)1.
Most have no name2.
Without names, cannot accomplosh first two categories3.
More effort needs to be spent on taxonomy 4.
What is the unit or group to be conserved?
Guest Lecture: Conservation Genetics
Thursday,+ March+ 16,+2017
10:25+AM