Conservation Genetics By: Capaccio, Rose Foschetti, Olivia Howland, Yvette Shahmehri, Nadia Strazzera, Josephine Younus, Muhammad
Conservation Biology + Genetics = Conservation Genetics Conservation biology is the study of individual species and populations that have been impacted by various human behaviors such as habitat loss and exploitation and/or environmental changes (learn.genetics.utah.edu) and finding ways to maintain and restore biodiversity. Conservation genetics is a mixture of ecology, molecular biology, population genetics, mathematical modeling and evolutionary systematics (learn.genetics.utah.edu). Once scientists understand the genetic relationships of an organism, they may proceed with an appropriate management technique to preserve the biological and genetic diversity of a species. http://learn.genetics.utah.edu/archive/conservation/index.html
Genetic management of small populations Conservation Genetics Frankham et al. 2002. Introduction to Conservation Genetics. Cambridge Univ. Press Conservation genetics is the application of genetics to preserve species as dynamic entities capable of coping with environmental change Genetic management of small populations Resolution of taxonomic uncertainties Identifying and defining units of conservation within and between species Use of genetic information for wildlife forensics Address genetic factors that affect extinction risk and genetic management to minimize or mitigate those risks
Importance / Goals of Conservation Genetics Genetics is a valuable resource towards conservation by reducing the amount of time spent of conserving the wrong population or on a population that may not be endangered (learn.genetics.utah.edu). Conservation genetics provides new information about the diversity among the individuals in a population. It is a tool to help maintain and restore population variability. Without genetic diversity, biodiversity may be lost.
5 broad categories of conservation genetics publications (Allendorf and Luikart) Management and reintroduction of captive populations, and the restoration of biological communities Description and identification of individuals, genetic population structure, kin relationships, and taxonomic relationships Detection and prediction of the effects of habitat loss, fragmentation and isolation Detection and prediction of the effects of hybridization and introgression Understanding the relationships between adaptation or fitness and the genetic characters of individuals or populations
Evolutionary genetics Taxonomic uncertainties Understanding species biology Introgression Conservation Genetics Population structure & fragmentation Forensics Small populations Outbreeding Inbreeding Mutational accumulation Loss of genetic diversity Reproductive fitness Extinction Genetic management Identify mgmt units Adaptation to captivity Wild Captive Reintroduction
Use of Conservation Genetics 1. Habitat Destruction A population is targeted by conservation managers when their habitat is or may be destroyed by human interference such as building homes or natural phenomena such as hurricanes. 2. Change in Population Size When a population is reduced in size, genetic diversity may be adversely affected. The smaller the population, the more likely to be susceptible to random or unexpected events. http://learn.genetics.utah.edu/archive/conservation/when.html
11 major genetic issues in conservation biology (Frankham et al.) Inbreeding and inbreeding depression Loss of genetic diversity and adaptive potential Population fragmentation and loss of gene flow Genetic drift becomes more important than natural selection as main evolutionary force Accumulation of deleterious mutations (lethal equivalents) Adaptation to captivity and consequences for captive breeding and reintroductions Taxonomic uncertainties masking true biodiversity or creating false biodiversity Defining ESUs and management units within species Forensic analyses Understand species biology Outbreeding depression
Tools 1. Protein Electrophoresis It compares the similar proteins between species found in a portion of the DNA sequence. 2. Chromosome Analysis It shows the differences in the number of chromosomes between closely related species. http://learn.genetics.utah.edu/archive/conservation/tools/index.html
Reduction in Gene Flow/ Metapopulation Gene flow is the gradual exchange of alleles between populations with the dispersal of gametes or the migration of individuals. Migration is the main route for gene flow in animals and cross pollination and seed dispersion in plants.
Habitat fragmentation has also led to a decline in gene flow among populations of threatened or endangered species due to the small separate colonies in which they exhist and their connection to their remaining habitat. Habitat fragmentation by isolated population of species, affects the gene flow because surviving population do not have movement between the populations to encourage gene flow. Metapopulation describes the occurrence of spatially separated subpopulations with limited gene flow that results in extinction or replacements over time. (W.Klug, M. Cummings, C. Spencer, M. Palladino; Essentials of Genetics; Seventh Edition; Pearsom Education, Inc. 2010; pp. 514-515)
Many studies of current gene flow are aimed at understanding gene movement on a regional or landscape scale. As continuous populations become fragmented, they may assume metapopulation dynamics, through extinction and recolonization events of the different fragments. Populations implicated in the metapopulation suffer genetic diversity and result in inbreeding depression. It is not clear whether recent modeling approaches in metapopulation biology and landscape ecology offer viable insight on gene movement. (http://www.nceas.ucsb.edu/nceas-web/projects/2057/nceas-paper3/data/Gfpart1.html). References: (W.Klug, M. Cummings, C. Spencer, M. Palladino; Essentials of Genetics; Seventh Edition; Pearsom Education, Inc. 2010; pp. 514-515) http://www.amjbot.org/cgi/content/full/94/1/128 http://www.nceas.ucsb.edu/nceas-web/projects/2057/nceas-paper3/data/Gfpart1.html
DNA Sequence Evolution -3O,OOO yrs -20,000 yrs -10,000 yrs today AAGACTT AGGACTT AAGATTT AGGACTT AAGATTT AAGGTTT AAGATTC AGGACTC AAGATTC AGGACTC AAGGTTT AAAGTTT AGGGCTC AGGATTC GAGATTC AAAGTTT GAGATTC AGGATTC AGGATTC AGGGCTC
Glossary biodiversity – the biological variation represented by different plants and animals genetic diversity – a measure of the possible choices of information provided by a gene Back to slide Back to slide
AAAGTTT AGGGCTC AGGATTC GAGATTC
DNA Sequence Evolution AAGACTT AGGACTT AAGATTT AGGACTT AAGATTT AAGGTTT AAGATTC AGGACTC AAGATTC AGGACTC AAGGTTT AAAGTTT AGGGCTC AGGATTC GAGATTC AAAGTTT GAGATTC AGGATTC AGGATTC AGGGCTC Homoplasy
Seeds of rare crop varieties, cryogenically preserved at the US Department of Agriculture National Seed Storage Laboratory
Growth in human population over the past 2000 years and projected through 2100
A coastal marsh in North Carolina exemplifies an ecosystem with low interspecific diversity
Phenotypic variation in seed color and markings in the common bean (Phaseolus vulgaris) reveals high levels of intraspecific diversity
The cheetah (Acinonyx jubatus)
Change in frequencies over ten generations for two sets of alleles, A/a and B/b, in a theoretical population subject to genetic drift
Increase in inbreeding coefficient (F) in theoretical populations as the population size (N) decreases
The Isle Royale gray wolf (Canis lupus)
The red-cockaded woodpecker (Picoides borealis)
Effects of bottlenecks in various populations on evolutionary potential in Drosophila, as shown by distributions of NaCl {Table Salt} concentrations at extinction
Effect of captive-population founder number on the probability of maintaining both A1 and A2 alleles at a locus
The black-footed ferret (Mustela nigripes)
The Florida panther (Puma concolor coryi)
Bibliography 1. The following article is a review of conservation of genetics. http://www.sciencedirect.com.library.esc.edu/science?_ob=MImg&_imagekey=B6TCY-4YKKK22-1-5&_cdi=5183&_user=683075&_pii=S016895251000003X&_origin=search&_zone=rslt_list_item&_coverDate=04%2F30%2F2010&_sk=999739995&wchp=dGLzVlb-zSkWb&md5=9d5e6caeb47dee13e1b235a80583303a&ie=/sdarticle.pdf Ouborg, N., Pertoldi, C., Loeschcke, V., Bijlsma, R., & Hedrick, P. (2010). Conservation genetics in transition to conservation genomics . Trends in Genetics, 26(4), 177-187. 2. This article is a review of the challenges and opportunities faced in conservation genetics from management to breeding systems. http://www.sciencedirect.com.library.esc.edu/science?_ob=MImg&_imagekey=B6V5X-508FKVH-1-2&_cdi=5798&_user=683075&_pii=S000632071000234X&_origin=search&_zone=rslt_list_item&_coverDate=09%2F30%2F2010&_sk=998569990&wchp=dGLzVlb-zSkWb&md5=3b982b4fc9aa31d0367f2aadc8d457c5&ie=/sdarticle.pdf Frankham, R. (2010). Challenges and opportunities of genetic approaches to biological conservation. Biological Conservation, 143(9), 1919-1927. 3. The following website is about “The AMNH Center for Conservation Genetics (ConGen) employs cutting-edge techniques in genetics, molecular biology, population biology, molecular ecology, and forensics to identify and ameliorate genetic threats to endangered species and to develop and support conservation strategies for retaining genetic diversity.” http://research.amnh.org/genomics/Programs/Conservation-Genetics 4. Conservation Genetics By Kris Hundertmark 5. Essentials of Genetics (7th Edition) ISBN: 0321618696