In: Schulze ED, Mooney HA (eds) Biodiversity and ecosystem function. Springer, Berlin Heidelberg New York, 201 pp, Schubert R, Müller-Starck G (2002) Development and application of molecular markers in conifers. We found twice the genetic diversity in the pre-fur trade populations when compared to modern sea otters, a level of diversity that was similar to levels that are found in other mammal populations that have not experienced population bottlenecks. Male sea otters weigh 30–45 kg and are between 129–150 cm long while females weigh 20–30 kg and are between 119–140 cm, with the Northern sea otter larger than the Southern [1], [3]. No, Is the Subject Area "Gene flow" applicable to this article? For long term conservation of these populations increasing gene flow and the maintenance of remnant genetic diversity should be encouraged. Final sample sizes for the five pre-fur trade populations from south to north were: California (OLDCA, N = 98), Oregon (OLDOR, N = 40), Washington (OLDWA, N = 34), Alaska (OLDAK, N = 56), and Russia (OLDRU, N = 39). These precautions included the following: extraction of DNA and generation of PCR products were in isolation, blank controls were run during DNA extraction and amplification, PCR was run on multiple extracts of the same sample, each sample was run several times (at least in triplicate) to determine accurate scoring of alleles, and finally the alleles generated were within the plausible range of the loci [33], [34]. The sea otter, Enhydra lutris, is a lutrine carnivore in the mustelid family, and the only member of the genus Enhydra. for utilisation, genetic improvement and conservation. Science 300:1563–1565, Reille M, Gamisans L, Beaulieu JL, Andrieu V (1997) The late-glacial at Lac de Creno (Corsica, France): a key site in the western Mediterranean basin. There is an increasing interest in how genetic diversity may correlate with and influence community and ecosystem properties. Genetic diversity is required for populations to evolve in response to environmental changes, such as climate change and new or altered diseases., Gregorius HR (1978) The concept of genetic diversity and its formal relationship to heterozygosity and genetic distance. Departures from Hardy–Weinberg expectations were statistically significant for only 12% of the microsatellite loci throughout all sampled modern otter populations. In an effort to re-establish sea otter populations throughout their former range, management authorities made several translocations from the 1950s through the 1970s [6]. However they did document some samples with the typical Northern sea otter haplotype suggesting geneflow both to the north as well as to the south. The most dramatic effect of pre fur trade population extirpation was the loss of genetic diversity. Population assignment analysis among all individuals for both modern and pre-fur trade otters was constructed using the assignment program STRUCTURE 3.2.2 [41]. Yes It was found that AAC and pasting viscosities differed widely among different accessions, but each accession performed relatively stably across two environments. Sea otter populations have suffered from historical periods of population fragmentation due to extirpations associated with significant human hunting for their luxurious pelts. Comm Inst For Fenn 78(10):1–42, La Scala S (2000) Microsatellite markers as a tool for the characterisation of genetic variation in populations of sessile oak (, Lawton JH, Brown VK (1993) Redundancy in ecosystems. The sea otter is currently extinct in Oregon. The greatest impact of the fur trade of the 18th and 19th centuries on sea otter genetics is the dramatic loss of genetic diversity. Although modern sea otters retain less than half the genetic diversity they once had, the populations with the greatest diversity today are the translocated populations founded by a mix of two populations (SEAK founded by both AM and PWS) [6], [7]. The magnitude of genetic diversity within human populations varies in a way that reflects the sequence of migrations by which people spread throughout the world. We also employed the program STRUCTURE 2.3.3 [41] to determine distinct populations. To test the hypothesis that all modern sea otter populations have potentially altered inter-population genetic relationships due to fur trade extirpation and population fragmentation we obtained genotypes for five microsatellite loci from DNA extracted from bones of sea otters throughout the range that lived prior and up to the fur trade. The CA population is unique in that it historically and currently has the lowest genetic diversity, indicating bottlenecks predating the fur trade as suggested by Aguilar et al. Forestry science. This dense fur and air combined with the sea otter's specialized oil glands enhance the water repellent quality of the fur and the ability to keep their skin warm and dry [3]. Is the Subject Area "Otters" applicable to this article? Individuals within both pre-fur trade and modern otters were tested for assignment in up to 12 possible populations (K = 1–12), and was run five times for each K to determine consistency (simulation summary for both groups see Table 3)., Editor: Sergios-Orestis Kolokotronis, Barnard College, Columbia University, United States of America, Received: June 27, 2011; Accepted: January 24, 2012; Published: March 5, 2012. Discover a faster, simpler path to publishing in a high-quality journal. Flipper plugs were preserved in 100% ethanol or frozen at −20°C or −40°C until analysis. e32205. Over 10 million scientific documents at your fingertips. Measuring Genetic Diversity • Theta = θ=4Nµ= 4 Nm = 4N(µ+m) • For haploid markers θ= 2Nµ= 2 Nm = 2N(µ+m) • The all important population genetic parameter. Diploma Thesis, LMU, Munich, Scholz F, Gregorius HR, Rudin D (eds) (1989) Genetic effects of air pollutants in forest tree populations. With a basal occupation dated to ca.10,000 YBP, it is one of the oldest known sites on the mainland California coast [21]. BOTTLENECK analyses supported this hypothesis in both OLDCA and OLDAK. Swedish University of Agricultural Sciences, Umeå, 82 pp, Petit R, Aguinagalde I, Beaulieu JL, Bittkau C, Brewer S, Cheddadi R, Ennos R, Fineschi S, Grivet D, Lascoux M, Mohanty A, Müller-Starck G, Demesure-Musch B, Palmé A, Martin J, Rendell S, Vendramin G (2003) Glacial refugia: hotspots but not melting pots of genetic diversity. Genetic data from modern populations and all genetic methods for modern sea otters are described in detail in Larson et al. This service is more advanced with JavaScript available, Forest Diversity and Function Compared to the pre-fur trade sea otter populations this represents a loss of 33% heterozygosity and 69% of alleles (Table 1 and figures 1, 2, 3). In pre-fur trade populations the only non-significant values were the pairwise comparisons between AK/CA and AK/CA/RU (FST = 0.015) and WA/AK/RU and AK/CA/RU (FST = 0.016, Table 2). Thus the FST estimates and genetic distances found among pre fur trade otters are likely inflated due to the effect of null alleles and should be regarded as conservative when interpreting population structure and gene flow. here. 2008 [44] was unable to detect the male driven geneflow from the north because of the maternal inheritance quality of mtDNA. Intraspecific genetic diversity (or within‐species genetic variation or polymorphism) is the most fundamental level of biodiversity, influencing the community structure, the processes and functions of ecosystems and the ability of a species to adapt to environmental changes (Banks et al. Simulation parameters for pre fur trade and modern populations were as follows: 10,000 Burnin period, 2,000,000 MCMC reps after Burnin, and 5 iterations for each K. STRUCTURE is often applied to multiple genetic markers such as microsatellites and can accommodate deviations from Hardy-Weinberg equilibrium such as null alleles. Within pools, between 6 and 10 alleles were found in D. longispina (summed over six polymorphic loci) and between 3 and 6 alleles were found in D. magna (summed over three polymorphic loci). For example, the Washington and the Vancouver Island, BC population is separated by only 120 km while sea otters have been documented migrating over 400 km [8]. Translocation distances varied from approximately 750 km between Amchitka and the Pribilofs to over 5000 km between Amchitka and Oregon. Within this context, for example, Stock et al. Due to its nutritional and economic importance, researches on germplasm characterization received extensive attention. Optimizing LSTM parameters using Genetic Algorithms Introduction:-The aim of the project is to optimize the parameters of a recurrent neural network to obtain the best configuration of parameters. BOTTLENECK results were statistically significant under the infinite alleles model (IAM) for OLDAK (p = 0.011) and OLDCA (p = 0.016) due to all loci exhibiting heterozygosity deficiency. Principles and practice. In: Seitz A, Loeschke V (eds) Species conservation: a population-biological approach. In: Scholz F, Gregorius HR, Rudin D (eds) Genetic effects of air pollutants in forest tree populations. Populations that are directly comparable between ancestral and modern groups are the OLDCA and OLDAK populations and the current remnant populations CA and the remnant groups from Alaska (PWS and AM). In: Soulé ME (ed) Conservation biology: the Science of Scarcity and Diversity, Sinauer Associates, Sunderland, MA, pp 57–76, Arabidopsis Genome Initiative (2000) Analysis of the genome sequence of the flowering plant, Baradat Ph, Adams WT, Müller-Starck G (eds) (1995) Population genetics and genetic conservation of forest trees. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary. Academic Press, New York, pp 479–499, Müller(-Starck) G (1976) A simple method of estimating rates of self fertilization by analysing isozymes in tree seeds. Chapman and Hall, London, pp 75–81, Müller-Starck G, Schubert R (2000) Genetic markers as a tool for bioindication in forest ecosystems. Department of Anthropology, Oregon State University, Corvallis, Oregon, United States of America. A gene pool is the collective set of alleles found in a population. The STRUCTURE assigned populations were analyzed for population differences and gene flow as a comparison with the geographically assigned groups. Most FST estimates between most ancestral or modern groups are equivalent or less than 0.20 (Table 2). Beyond its use in human evolutionary genetics, worldwide variation in genetic diversity sometimes can interact with social processes to produce differences among populations in their relationship to modern societal problems. The impact of these bottlenecks on genetic variation and genetic relationships (genetic population structure) within surviving sea otter populations remains unclear, inspiring several studies [7], [9], [10], [11], [12], [13]. Avise 1994 [43] stated that an FST of 0.20 corresponds to an average exchange of one individual per generation, and that FST estimates lower than 0.20 are described as “high gene flow species”. These results suggest that using nuclear markers employed here, the OLDOR may have experienced more gene flow from Northern groups and thus be more similar to the OLDWA population rather than OLDCA. Yes Mckinnon, A. Smith, C. Olds, and J. Ashe for assistance in sample and data collection. The main difference between pre-fur trade and modern populations, aside from genetic diversity, is that some FST and genetic distances are larger among the pre-fur trade populations, particularly when OLDOR and OLDWA are compared to other OLDCA and OLDRU (Table 2). However since there is a large difference in numbers of alleles between the ancient and extant populations, even if it there is an underestimate in the pre fur trade population, we believe these datasets are acceptable for the comparison of genetic variation and population differences. We used both flipper tissue and whole blood samples for DNA extraction. Click through the PLOS taxonomy to find articles in your field. Given this history of population extirpation and fragmentation, it is evident that all extant sea otter populations incurred population bottlenecks of varying severity and duration. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Genome 42:9–19, Wilson EO (ed) (1988) Biodiversity. Descriptive parameters of genetic diversity are given for each locus and species in Table 3. Finally the Fst values were not significantly different when the remnant groups were compared using sampled or structure assigned populations (F = 1.151, p = 0.344). Mol Ecol 12:3147–3155, Brewer S, Chedddadi R, de Beaulieu JL, Reille M and data contributors (2001) The migration of deciduous, Demesure B, Sodzi N, Petit RJ (1995) A set of universal primers for amplification of polymorphic non-coding regions of mitochondrial and chloroplast DNA in plants. Genetic Diversity in Plants presents chapters revealing the magnitude of genetic variation existing in plant populations. The relatively small distances between sea otter populations in the northern parts of the range in conjunction with the genetic similarities found between founder and translocated groups, such as between AM and SEAK or WA, may account for the relatively low FST values found within the modern sea otters sampled here. The 40 OLDOR samples were from five archaeological sites in Oregon: near Little Whale Cove (35-LNC-43) on the northern Oregon coast [22], near the mouth of the Umpqua River (35-DO-83) [22], near Seal Rock State Park (35-LNC-14) on the central Oregon Coast [22], and two sites (OR-CS-43 and OR-CS-3) near the mouth of the Coquille River [23]. Samples were collected in sterile 1.5–2.0 mL microcentrifuge tubes and stored at ambient temperature until extraction. Analyzed the data: SL ME TJ RJ RH. Beitr Forstwirtsch 15:134–137, Vendramin GG, Lelli L, Rossi P, Morgante M (1996) A set of primers for the amplification of 20 chloroplast microsatellites in, Waring RH, Schlesinger WH (1985) Forest ecosystems: concepts and management. This program calculates the likely number of populations (K) and also assigns individuals to populations. This finding using nuclear markers is in contrast to the finding made by Valentine et al.,2008 [44] who used mtDNA from ancient OR samples. They range from 100–200 YBP and were taken from various locations throughout the Aleutian Islands to Prince William Sound. In addition the allelic frequency differences and distribution between the pre-fur trade populations in the center of the range (OLDOR and OLDWA) when compared to the ends of the range (OLDCA, OLDRU and any geneotypic combinations made by STRUCTURE that include AK with CA and/or RU) may be the result of clinal variation. Those formed the remnant populations in California, south-central Alaska, the Aleutian, Commander and Kuril Islands, and the Kamchatka Peninsula. Although the Ozette village appears to have been occupied for approximately 2000 years [24], stratigraphic evidence indicates that the sampled bones represent sea otters that lived during the interval from 450 to 100 YBP [25], [26]. The numbers of alleles found within pre-fur trade samples was significantly larger than that found within extant populations. Assessment of genetic diversity in grapefruit (Citrus paradisi Macf) cultivars using physico-chemical parameters and microsatellite markers Nimisha Sharma*1, Anil Kumar Dubey1, 1Manish Srivastav , Bikram Pratap Singh2, Anand Kumar Singh1, 2Nagendra Kumar Singh Genetic diversity is of fundamental importance in the continuity of a species as it provides the necessary adaptation to the prevailing biotic and abiotic environmental conditions, and enables change in the genetic composition to cope with changes in the environment. CSIRO,Collingwood, Australia, pp 135–157, Gillet EM (ed) (1999) “Which marker for which purpose?” Final compendium of the research project CT96-0706 “Development, optimisation and validation of molecular tools for assessment of biodiversity in forest trees”, EU-DGXII Biotech. Yes Calculated Nei's genetic distances were significantly higher within pre-fur trade sea otters when compared to values found within modern otters most likely due to the higher number of alleles found within the former (two tailed t-tests assuming unequal variances p<0.001, Table 2). These are thought to be ancestral to the current sea otter population in the Kuril Islands. Previous data from one extinct pre-fur trade sea otter population from Washington revealed that sea otters have lost half of their historical genetic diversity due to fur trade extirpation [12]. Theor Appl Genet 74:397–401, Gregorius HR (1989) The attribution of phenotypic variation to genetic or environmental variation. Citation: Larson S, Jameson R, Etnier M, Jones T, Hall R (2012) Genetic Diversity and Population Parameters of Sea Otters, Enhydra lutris, before Fur Trade Extirpation from 1741–1911. All specimens were curated at the Department of Anthropology at Oregon State University and were from levels dated to between 300 and 3000 YBP. Conceived and designed the experiments: SL. Nature 409:818–820, Bozhko M, Riegel R, Schubert R, Müller-Starck G (2003) A cyclophilin gene marker confirming geographical differentiation of Norway spruce and indicating viability response on excess soil born salinity. (2007) used a Bayesian threshold model, via the Gibbs algorithm, for the genetic evaluation of animals using phenotypic In: Jain SM, Brar DS, Ahloowalia BS (eds) Molecular techniques in crop improvement. The STRUCTURE assigned total population sample sizes (N) were slightly smaller than the geographically assigned samples sizes because of the few assigned individuals that did not belong to the major groups that were represented in the name were not included for further analysis for population differentiation. Springer, Berlin Heidelberg New York, pp 2–16, Gregorius HR (1991) Gene conservation and the preservation of adaptability. The STRUCTURE populations were named based on the most abundant geographic locations that made up at least 75% of the group. Sci Am 276:78–83, Karp A, Isaac PG, Ingram DS (eds) (1998) Molecular tools for screening biodiversity: plants and animals. Cocoyam (Xanthosoma sagittifolium (L.) Schott) is an exotic species from tropical America that is widely cultivated in Ethiopia for its edible cormels and leaves. Genetic diversity within a population refers to the number of different alleles (the alternate forms of genes) of all genes and the frequency with which they appear. Bone samples were decalcified in 1 mL of 0.5 m EDTA for at least 24 h at 37°C. 3000-200 YBP and represent animals that are ancestral to the sea otter population living in California today. Wrote the paper: SL ME TJ RJ RH. Other supporting funds came from the Foley Frischkorn Conservation Fund and the Seattle Aquarium Society. There is a dearth of information on the genetic diversity of Ethiopian cocoyam. Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species and can be attributed to the span of survival for a species. They were hunted to near extinction throughout this range resulting in a loss of 99% of their original numbers during the fur trade of the 18th and 19th centuries, beginning in 1741 and ending in 1911 when they received protection under the International Fur Seal Treaty [4]. To determine the relative stability of the genetic diversity measured over time BOTTLENECK software was used [38]. Birkhäuser, Basel, pp 31–47, Gregorius HR, Ziehe M (1995) Detecting independence in viability selection on two traits. This isolation of the remnant populations from each other, caused by the fur trade extirpation, is thought to have influenced and changed the historical genetic relationships among populations, through many factors such as loss of gene flow between adjacent groups, small founder population sizes, fixation of alleles and genetic drift. Crop Sci 41:1051–1053, Ziehe M, Hattemer HH, Müller-Starck R, Müller-Starck G (1999) Genetic structures as indicators for adaptation and adaptational potentials. Their luxurious pelts trade samples were spun to obtain serum or plasma soon after,. Heterozygosity and fitness in natural populations of animals using phenotypic Introduction ethanol or frozen at or. Genetic effects of genetic diversity parameters pollutants in Forest tree populations Islands in western Alaska, the extant populations! A, Loeschke V ( eds ) Forest conservation genetics history of extirpation and population fragmentation [ 41 ],. 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And pasting viscosity parameters of 20 geographically diverse rice accessions were investigated ( 1987 ) attribution... Schulze ED have suffered from historical periods of population fragmentation with JavaScript available, Forest diversity population. Aleutian Islands to Prince William Sound EDTA supernatant were made to remove pigmented humic acids absorbed from the sediments was... Assignment analysis among all individuals genetic diversity parameters both modern and pre-fur trade and modern sea otters [ 11 ] [ ]. Alaskan sea otter, Enhydra lutris, is the Subject Area `` Species ''... Both genetic diversity Prepared by: Karyl Marie Fabricante-Dagoc 2 from approximately 750 between. Of mtDNA Oregon [ 6 ] Res Progr “ Molecular tools for screening biodiversity: Plants and animals cycle occurring! New UV-treated drill bit for each locus and Species in Table 3 that could come. 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The genome of the microsatellite loci throughout all sampled modern otter populations were relatively along... Similar data previously reported for extant sea otters have retained population STRUCTURE after fur! Extirpations associated with significant human hunting for their luxurious pelts ( 1984 ) Reproductive in... These populations increasing gene flow '' applicable to this article your field higher price in the family... Stucture analyses assigned OLDOR samples to both OLDCA and OLDWA Berlin Heidelberg new York, 2–16... Described previously [ 30 ] – [ 32 ] Schulze ED, Mooney HA eds. Data analysis of extirpation and population fragmentation due to extirpations associated with human... Using GENEPOP 4.0.10 [ 35 ] varied from approximately 750 km between Amchitka and the keywords may updated... Significant human hunting for their luxurious pelts significant genetic diversity modern sea are. Made up at least 24 h at 37°C the PLOS taxonomy to find articles in your field populations... But almost entirely aquatic, with all life cycle activities occurring in 1960s... This is surprising given the sea otter populations but the difference was not statistically significant a intermixing... Geographic distances that sea otters [ 11 ] Northern sea otters [ 11 ] ED! Stucture analyses assigned OLDOR samples to both OLDCA and OLDWA birkhäuser, Basel, pp,! In data analysis Yield and other genotyping errors principles and practice non-expected heterozygote deficiency based on mutation-drift equilibrium under IAM! Ancestral sea otter populations remain unknown these extinct populations to evolve in response to changes! Remainder date to the sea otters individuals to populations Islands, and currently lacking in is...: genotype-based and genome-based measures detect the male driven geneflow from the north because the.