686:
774:
inbreeding, the harshness of the environment or of the competitive conditions, etc. The effects of purging were first noted by Darwin in plants, and have been detected in laboratory experiments and in vertebrate populations undergoing inbreeding in zoos or in the wild, as well as in humans. The detection of purging is often obscured by many factors, but there is consistent evidence that, in agreement with the predictions explained above, slow inbreeding results in more efficient purging, so that a given inbreeding F leads to less threat to population viability if it has been produced more slowly.
81:
fitness mean fitness declines less than would be expected just from inbreeding and, after some initial decline, it can even rebound up to almost its value before inbreeding. Another consequence is the reduction of the so-called inbreeding load. This means that, after purging, further inbreeding is expected to be less harmful. The efficiency of purging is reduced by genetic drift and, therefore, in the long term, purging is less efficient in smaller populations. Purging can be increased if individuals mate with relatives more often than expected by random mating.
2521:
2137:
716:=10), and remains that small for many generations. As inbreeding increases, the probability of being homozygous for one (or more) of these lethal alleles also increases, causing fitness to decline. However, as those lethals begin to occur in homozygosis, natural selection begins purging them. The figure to the right gives the expected decline of fitness against the number of generations, taking into account just the increase in inbreeding
73:
probability of being homozygous, it increases the fraction of the potential deleterious effect that is expressed and, therefore, exposed to selection. This causes some increase in the selective pressure against (partially) recessive deleterious alleles, which is known as purging. Of course, it also causes some reduction in fitness, which is known as
785:
In addition, part of the inbreeding depression could be not due to deleterious alleles, but to an intrinsic advantage of being heterozygous compared to being homozygous for any available allele, which is known as overdominance. Inbreeding depression caused by overdominance cannot be purged, but seems
286:
and, therefore, the final reduction in fitness. This implies that, if inbreeding progresses slowly enough, no relevant inbreeding depression is expected in the long term. implies, for example, that the average fitness of a population that has been moderately small for a long time, can be very similar
241:
can also be computed, to a good approximation, using simple expressions in terms of the population size or of the genealogy of individuals (see BOX 1). However this requires some information on the magnitude of the deleterious effects that are hidden in the heterozygous condition but become expressed
711:
As an example of genetic purging, consider a large population where there are recessive lethal alleles segregating at very low frequency in many loci, so that each gamete carries on the average one of these alleles. Although about 63% of the gametes carry at least one of these lethal alleles, almost
273:
for the extreme case of inbreeding depression caused by recessive lethals, which are alleles that cause death before reproduction but only when they occur in homozygosis. Purging is less effective against mildly deleterious alleles than against lethal ones but, in general, the slower is the increase
80:
Purging can reduce the average frequency of deleterious alleles across the genome below the value expected in a non-inbred population during long periods. which reduces the negative impact of inbreeding on fitness. If inbreeding is due just to random mating in a finite population, due to purging the
799:
Understanding genetic purging and predicting its consequences is of great importance in evolutionary and conservation genetics. Endangered populations use to undergo inbreeding due to their reduced numbers, and purging can play a relevant role in determining their extinction risk and the success of
72:
by more than twice than when they occur in heterozygosis (single copy). In other words, part of their potential deleterious effect is hidden in heterozygosis but expressed in homozygosis, so that selection is more efficient against them when they occur in homozygosis. Since inbreeding increases the
33:
Purging occurs because deleterious alleles tend to be recessive, which means that they only express all their harmful effects when they are present in the two copies of the individual (i.e., in homozygosis). During inbreeding, as related individuals mate, they produce offspring that are more likely
777:
Nevertheless, in practical situations, the genetic change in fitness also depends on many other factors, besides inbreeding and purging. For example, adaptation to changing environmental conditions often causes relevant genetic changes during inbreeding. Furthermore, if inbreeding is due to a
773:
When a previously stable population undergoes inbreeding, if nothing else changes, natural selection should consist mainly of purging. The joint consequences of inbreeding and purging on fitness vary depending on many factors: the previous history of the population, the rate of increase of
159:
is the standard measure of inbreeding, and gives the probability that, at any given neutral locus, an individual has inherited two copies of a same gene of a common ancestor (i.e. the probability of being homozygous "by descent"). In simple conditions,
872:
Kleinman-Ruiz, D., Lucena-Perez, M., Villanueva, B., Fernández, J., Saveljev, A. P., Ratkiewicz, M., ... & Godoy, J. A. (2022). Purging of deleterious burden in the endangered
Iberian lynx. Proceedings of the National Academy of Sciences, 119(11),
728:). This example shows that purging can be very efficient in preventing inbreeding depression. However, for non-lethal deleterious alleles, the efficiency of purging would be smaller, and it can require larger populations to overcome genetic drift.
1013:
Mortimer, Robert K.; Romano, Patrizia; Suzzi, Giovanna; Polsinelli, Mario (December 1994). "Genome renewal: A new phenomenon revealed from a genetic study of 43 strains ofSaccharomyces cerevisiae derived from natural fermentation of grape musts".
712:
no individual carry two copies of the same lethal. Therefore, since lethals are considered completely recessive (i.e., they are harmless in heterozygosis), they cause almost no deaths. Now assume that population size reduces to a small value (say
736:
Inbreeding depression and purging play a major role in the evolution of reproductive systems. As an example, they determine when selfing becomes at an advantage compared to outcrossing. Another example is the genomic renewal in yeasts.
119:
Purging reduces inbreeding depression in two ways: first, it slows its progress; second, it reduces the overall inbreeding depression expected in the long term. The slower the progress of inbreeding, the more efficient is purging.
214:) that gives the probability of being homozygous by descent for (partially) recessive deleterious alleles, taking into account how their frequency is reduced by purging. Due to purging, fitness declines at the same rate
34:
to be homozygous so that deleterious alleles express all their harmful effects more often, making individuals less fit. Those less fit individuals pass fewer copies of their genes to future generations. In other terms,
789:
Therefore, predicting the actual evolution of fitness during inbreeding is highly elusive. However, the component of fitness decline expected from inbreeding and purging on deleterious alleles could be predicted using
97:, because inbreeding depression may be a relevant factor determining the extinction risk of endangered populations, and because conservation programs can allow some breeding handling in order to control inbreeding.
268:
can approach a much smaller final value. Hence, it is not just that purging slows the fitness decline, but also that it reduces the overall fitness loss produced by inbreeding in the long term. This is illustrated
287:
to that of a large population with more genetic diversity. In conservation genetics, it would be very useful to ascertain the maximum rate of increase of inbreeding that allows for such efficient purging.
320:, due to (partially) recessive deleterious alleles that were present at low frequencies at different loci. This means that, in the absence of selection, the expected value for mean fitness after
89:
Accounting for purging when predicting inbreeding depression is important in evolutionary genetics, because the fitness decline caused by inbreeding can be determinant in the evolution of
128:
In the absence of natural selection, mean fitness would be expected to decline exponentially as inbreeding increases, where inbreeding is measured using Wright's inbreeding coefficient
481:
383:
935:
Porcher, E., & Lande, R. (2013). Evaluating a simple approximation to modeling the joint evolution of self-fertilization and inbreeding depression. Evolution, 67(12), 3628-3635.
672:
191:
for neutral loci does not apply to deleterious alleles, unless inbreeding increases so fast that the change in gene frequency is governed just by random sampling (i.e., by
1284:
Hedrick, P. W., & Garcia-Dorado, A. (2016). Understanding inbreeding depression, purging, and genetic rescue. Trends in ecology & evolution, 31(12), 940-952.
511:
413:
1452:
765:. Recessive deleterious mutations accumulate during the diploid expansion phase, and are purged during selfing: this purging has been termed "genome renewal".
181:
However, the above prediction for the fitness decline rarely applies, since it was derived assuming no selection, and fitness is precisely the target trait of
2359:
199:
1240:
GarcĂa-Dorado, A. (2015). On the consequences of ignoring purging on genetic recommendations for minimum viable population rules. Heredity, 115(3), 185.
701:) of maintenance with population size N=10 when, in the original population, each gamete carried on the average one rare recessive lethal. Evolution of
944:
GarcĂa-Dorado, Aurora. An explicit model for the inbreeding load in the evolutionary analysis of selfing. Evolution, 2017, vol. 71, no 5, p. 1381-1389.
1312:
68:
organisms have a remarkable trend to be, at least, partially recessive. This means that, when they occur in homozygosis (double copies), they reduce
1560:
1555:
1957:
1789:
2384:
2007:
100:
In brief: due to purging, inbreeding depression does not depend on the standard measure of inbreeding (Wright's inbreeding coefficient
2125:
424:
However, since selection operates upon fitness, mean fitness should be predicted taking into account both inbreeding and purging, as
2059:
45:
Purging reduces both the overall number of recessive deleterious alleles and the decline of mean fitness caused by inbreeding (the
2506:
1987:
52:
The term "purge" is sometimes used for selection against deleterious alleles in a general way. It would avoid ambiguity to use "
290:
826:"Understanding and predicting the fitness decline of shrunk populations: inbreeding, purging, mutation and standard selection"
1305:
140:
instead of linear is just that fitness is usually considered a multiplicative trait). The rate at which fitness declines as
2364:
2208:
2379:
2173:
2042:
1779:
2054:
1432:
93:, sexual reproduction and other main biological features. It is also important in animal breeding and, of course, in
2575:
2022:
1548:
1298:
786:
to be a minor cause of overall inbreeding depression, although its actual importance is still a matter of debate.
2097:
1889:
1828:
1382:
150:) depends on the frequencies and deleterious effects of the alleles present in the population before inbreeding.
1806:
1488:
1372:
1332:
1062:"The consequences of rare sexual reproduction by means of selfing in an otherwise clonally reproducing species"
430:
332:
2565:
2545:
2140:
1879:
1714:
1538:
1518:
685:
291:
Predictive model for the joint effects of inbreeding and purging caused by a reduction in population numbers
2550:
2465:
2102:
1845:
1640:
1635:
1513:
2120:
2027:
2012:
1811:
1696:
1625:
1528:
1422:
722:(red line), or both inbreeding and purging (blue line, computed using the purged inbreeding coefficient
525:, which represents the deleterious effects that are hidden in heterozygosis but exposed in homozygosis.
2570:
2213:
1962:
1570:
1362:
534:
2555:
2369:
2354:
2002:
1982:
1967:
1937:
1833:
308:
2374:
2193:
2130:
2047:
2017:
1997:
1605:
1523:
1508:
1498:
1473:
1468:
782:
can become less efficient, and this can induce additional fitness decline in the medium-long term.
739:
1972:
1874:
1821:
1580:
1503:
745:
202:, the decline of fitness can be predicted using, instead of the standard inbreeding coefficient
2166:
2037:
2032:
1952:
1947:
1942:
1932:
1914:
1899:
1753:
1412:
528:
The average "purged inbreeding coefficient" can be approximated using the recurrent expression
56:" in that general context, and to reserve "purging" to its more strict meaning defined above.
2501:
2335:
2300:
1992:
1977:
1798:
1719:
1691:
1686:
1645:
1615:
1610:
1575:
1493:
1437:
1377:
1367:
94:
74:
46:
2400:
2218:
2087:
2077:
1884:
1681:
1630:
1620:
1585:
1483:
1478:
1442:
1407:
1402:
1397:
1342:
1321:
1263:
1197:
1073:
967:
956:"Population genomics of the wild yeast Saccharomyces paradoxus: Quantifying the life cycle"
892:
750:
489:
391:
1186:"Role of inbreeding depression and purging in captive breeding and restoration programmes"
8:
2480:
2470:
2430:
2330:
2310:
2203:
2198:
1894:
1869:
1862:
1784:
1706:
1427:
1417:
1387:
53:
1352:
1201:
1077:
971:
896:
2440:
2325:
2320:
2295:
1850:
1724:
1655:
1447:
1223:
1166:
1153:
1136:
1094:
1061:
1039:
990:
955:
850:
825:
2560:
2524:
2455:
2445:
2435:
2269:
2159:
2107:
1816:
1774:
1660:
1543:
1267:
1215:
1210:
1185:
1158:
1099:
1031:
995:
855:
182:
107:
69:
35:
1227:
1170:
1043:
707:
expected only from inbreeding (red line) or from inbreeding and purging (blue line).
110:
alleles. Instead, fitness decline it depends on the "purged inbreeding coefficient"
2485:
2460:
1838:
1533:
1357:
1259:
1205:
1148:
1089:
1081:
1023:
985:
975:
900:
845:
837:
166:
can be easily computed in terms of population size or of genealogical information.
270:
2345:
1565:
904:
841:
680:
2475:
2415:
2315:
1595:
1117:
1085:
677:
There are also predictive equations to be used with genealogical information.
2539:
2092:
2082:
1855:
1746:
1734:
1729:
192:
980:
2425:
2305:
1769:
1271:
1219:
1162:
1103:
1057:
999:
859:
280:, the smaller becomes the final value of the purged inbreeding coefficient
1290:
1035:
1027:
2405:
762:
84:
2410:
2279:
2259:
2234:
311:
should be used here), leading to a progressive increase of inbreeding.
242:
in homozygosis. The larger this magnitude, denoted purging coefficient
39:
27:
954:
Tsai, I. J.; Bensasson, D.; Burt, A.; Koufopanou, V. (14 March 2008).
1909:
1741:
1250:
Crow, JF (2008). "Mid-century controversies in population genetics".
731:
519:
generations of inbreeding. It depends upon the "purging coefficient"
249:
An interesting property of purging is that, during inbreeding, while
116:, which takes into account how deleterious alleles are being purged.
2450:
2420:
2264:
2254:
2182:
1665:
1392:
1122:
The effects of cross and selffertilisation in the vegetable kingdom
779:
90:
22:
is the increased pressure of natural selection against deleterious
301:. Then, the size of the population reduces to a new smaller value
1137:"Purging the genetic load: a review of the experimental evidence"
758:
754:
415:
is the population mean for Wright's inbreeding coefficient after
65:
23:
778:
reduction in population size, selection against new deleterious
16:
Reduction in frequency of deleterious alleles through inbreeding
2274:
2249:
1650:
178:), but should not be confused with the coancestry coefficient.
1012:
681:
The example of inbreeding depression due to recessive lethals
2151:
953:
749:
have a life cycle that alternates between long periods of
2244:
2239:
295:
Consider a large non-inbred population with mean fitness
220:
than in the absence of selection, but as a function of
537:
513:
is the average "purged inbreeding coefficient" after
492:
433:
394:
335:
85:
The joint effect of inbreeding and purging on fitness
732:Relevance to the evolution of reproductive systems
666:
505:
475:
407:
377:
64:Deleterious alleles segregating in populations of
2537:
1561:Other effective area-based conservation measures
1556:Integrated Conservation and Development Project
1134:
960:Proceedings of the National Academy of Sciences
883:Frankham, R (2005). "Genetics and extinction".
123:
2167:
1306:
923:An Introduction to Population Genetics Theory
823:
1183:
314:Then inbreeding depression occurs at a rate
1320:
1056:
2174:
2160:
1313:
1299:
920:
146:increases (the inbreeding depression rate
134:(the reason why decline is exponential on
1209:
1152:
1093:
989:
979:
849:
1135:Crnokrak, P.; Barrett, S. C. H. (2002).
882:
819:
817:
815:
813:
768:
684:
476:{\displaystyle W_{t}=We^{-\delta g_{t}}}
378:{\displaystyle W_{t}=We^{-\delta F_{t}}}
185:. Thus, Wright's inbreeding coefficient
38:purges recessive deleterious alleles in
2507:List of genetics research organizations
2538:
1264:10.1146/annurev.genet.42.110807.091612
1116:
106:), since this measure only applies to
2155:
1294:
1184:Leberg, P. L.; Firmin, B. D. (2008).
810:
757:that is usually immediately followed
326:generations of inbreeding, would be:
208:, a "purged inbreeding coefficient" (
1249:
1060:; Lyttle, David N. (December 2011).
916:
914:
255:increases approaching a final value
235:This purged inbreeding coefficient
13:
1154:10.1111/j.0014-3820.2002.tb00160.x
172:is often denoted using lowercase (
14:
2587:
1433:Conservation biology of parasites
911:
695:) against number of generations (
246:, the more efficient is purging.
2520:
2519:
2136:
2135:
1549:Tropical rainforest conservation
1453:Vulnerability and susceptibility
1211:10.1111/j.1365-294x.2007.03433.x
667:{\displaystyle g_{t}=\left\left}
59:
2098:NatureServe conservation status
1383:Conservation-induced extinction
1278:
1243:
1234:
1177:
1128:
1110:
921:Crow, J.F.; Kimura, M. (1970).
1489:Conservation management system
1373:Conservation-dependent species
1333:Index of conservation articles
1066:Theoretical Population Biology
1050:
1006:
947:
938:
929:
876:
866:
1:
1715:Assisted natural regeneration
1519:Ecoregion conservation status
803:
2466:Missing heritability problem
2181:
2103:Special Area of Conservation
1641:Landscape-scale conservation
1636:High conservation value area
1514:Community-based conservation
905:10.1016/j.biocon.2005.05.002
689:Average population fitness (
198:Therefore, according to the
7:
2121:List of conservation issues
1529:Evidence-based conservation
1423:Mutualisms and conservation
842:10.1534/genetics.111.135541
800:conservation strategies.
421:generations of inbreeding.
124:A more detailed explanation
10:
2592:
1571:Roadless area conservation
1363:Compassionate conservation
2515:
2494:
2393:
2344:
2288:
2227:
2189:
2116:
2070:
1925:
1762:
1705:
1674:
1594:
1461:
1341:
1328:
1252:Annual Review of Genetics
1086:10.1016/j.tpb.2011.08.004
824:GarcĂa-Dorado, A (2012).
309:effective population size
1958:Central African Republic
1606:Conservation designation
1524:Environmental protection
1509:Conspicuous conservation
1499:Conservation photography
1474:Conservation development
1469:Conservation agriculture
753:as a diploid, ending in
740:Saccharomyces cerevisiae
2576:Rare breed conservation
1697:Human–wildlife conflict
1581:Site-based conservation
1504:Conservation psychology
1322:Conservation of species
981:10.1073/pnas.0707314105
925:. NY: Harper & Row.
885:Biological Conservation
746:Saccharomyces paradoxus
486:In the above equation,
1754:Species reintroduction
1413:Latent extinction risk
1124:. London: John Murray.
708:
668:
507:
477:
409:
379:
153:The above coefficient
2502:List of genetic codes
2126:List of organisations
1780:Hawaiian honeycreeper
1720:Ecosystem restoration
1692:Habitat fragmentation
1687:Fortress conservation
1646:Marine protected area
1616:Conservation easement
1611:Conservation district
1576:Roadside conservation
1494:Conservation movement
1438:Species translocation
1378:Conservation genetics
1368:Conservation behavior
1028:10.1002/yea.320101203
769:Evidence and problems
688:
669:
508:
506:{\displaystyle g_{t}}
478:
410:
408:{\displaystyle F_{t}}
380:
95:conservation genetics
75:inbreeding depression
47:inbreeding depression
2566:Conservation biology
2546:Evolutionary biology
2401:Behavioural genetics
2088:Planetary boundaries
2078:Conservation officer
1682:Conservation refugee
1631:Habitat conservation
1621:Conservation reserve
1586:Wetland conservation
1484:Conservation grazing
1479:Conservation finance
1443:Conservation welfare
1408:In-situ conservation
1403:Extinction threshold
1398:Ex-situ conservation
751:asexual reproduction
535:
490:
431:
392:
333:
2551:Population genetics
2481:Population genomics
2471:Molecular evolution
2431:Genetic engineering
1428:Nature conservation
1418:Marine conservation
1388:Conservation status
1202:2008MolEc..17..334L
1078:2011TPBio..80..317M
972:2008PNAS..105.4957T
897:2005BCons.126..131F
54:purifying selection
2441:Genetic monitoring
1725:Island restoration
1656:Open space reserve
1448:Threatened species
709:
664:
503:
473:
405:
375:
2571:Genetics concepts
2533:
2532:
2456:He Jiankui affair
2446:Genetic genealogy
2436:Genetic diversity
2365:the British Isles
2270:Genetic variation
2149:
2148:
2108:Soil conservation
1661:Wildlife corridor
1544:Forest protection
1539:Forest management
1190:Molecular Ecology
1147:(12): 2347–2358.
1022:(12): 1543–1552.
966:(12): 4957–4962.
761:, with only rare
619:
580:
183:natural selection
36:natural selection
2583:
2556:Applied genetics
2523:
2522:
2486:Reverse genetics
2461:Medical genetics
2176:
2169:
2162:
2153:
2152:
2139:
2138:
2023:Papua New Guinea
1915:Cryopreservation
1880:Gray nurse shark
1534:Flagship species
1358:Captive breeding
1315:
1308:
1301:
1292:
1291:
1285:
1282:
1276:
1275:
1247:
1241:
1238:
1232:
1231:
1213:
1181:
1175:
1174:
1156:
1132:
1126:
1125:
1114:
1108:
1107:
1097:
1054:
1048:
1047:
1010:
1004:
1003:
993:
983:
951:
945:
942:
936:
933:
927:
926:
918:
909:
908:
880:
874:
870:
864:
863:
853:
836:(4): 1461–1476.
821:
795:
727:
721:
706:
700:
694:
673:
671:
670:
665:
663:
659:
658:
657:
625:
621:
620:
618:
607:
602:
601:
586:
582:
581:
579:
568:
547:
546:
524:
518:
512:
510:
509:
504:
502:
501:
482:
480:
479:
474:
472:
471:
470:
469:
443:
442:
420:
414:
412:
411:
406:
404:
403:
384:
382:
381:
376:
374:
373:
372:
371:
345:
344:
325:
319:
306:
300:
285:
279:
267:
261:
254:
240:
231:
225:
219:
213:
207:
190:
177:
171:
165:
158:
145:
139:
133:
115:
105:
2591:
2590:
2586:
2585:
2584:
2582:
2581:
2580:
2536:
2535:
2534:
2529:
2511:
2490:
2389:
2380:the Middle East
2346:Archaeogenetics
2340:
2284:
2223:
2185:
2180:
2150:
2145:
2112:
2066:
1921:
1839:Indian elephant
1758:
1701:
1670:
1666:30 by 30 target
1597:
1590:
1566:Riparian buffer
1457:
1344:
1337:
1324:
1319:
1289:
1288:
1283:
1279:
1248:
1244:
1239:
1235:
1182:
1178:
1133:
1129:
1115:
1111:
1055:
1051:
1011:
1007:
952:
948:
943:
939:
934:
930:
919:
912:
881:
877:
871:
867:
822:
811:
806:
794:
791:
771:
734:
726:
723:
720:
717:
705:
702:
699:
696:
693:
690:
683:
647:
643:
630:
626:
611:
606:
591:
587:
572:
567:
560:
556:
555:
551:
542:
538:
536:
533:
532:
523:
520:
517:
514:
497:
493:
491:
488:
487:
465:
461:
454:
450:
438:
434:
432:
429:
428:
419:
416:
399:
395:
393:
390:
389:
367:
363:
356:
352:
340:
336:
334:
331:
330:
324:
321:
318:
315:
305:
302:
299:
296:
293:
284:
281:
278:
275:
266:
263:
259:
256:
253:
250:
239:
236:
230:
227:
224:
221:
218:
215:
212:
209:
206:
203:
189:
186:
176:
173:
170:
167:
164:
161:
157:
154:
144:
141:
138:
135:
132:
129:
126:
114:
111:
104:
101:
87:
62:
20:Genetic purging
17:
12:
11:
5:
2589:
2579:
2578:
2573:
2568:
2563:
2558:
2553:
2548:
2531:
2530:
2528:
2527:
2516:
2513:
2512:
2510:
2509:
2504:
2498:
2496:
2492:
2491:
2489:
2488:
2483:
2478:
2476:Plant genetics
2473:
2468:
2463:
2458:
2453:
2448:
2443:
2438:
2433:
2428:
2423:
2418:
2416:Genome editing
2413:
2408:
2403:
2397:
2395:
2394:Related topics
2391:
2390:
2388:
2387:
2382:
2377:
2372:
2367:
2362:
2357:
2351:
2349:
2342:
2341:
2339:
2338:
2333:
2328:
2323:
2318:
2316:Immunogenetics
2313:
2308:
2303:
2298:
2292:
2290:
2286:
2285:
2283:
2282:
2277:
2272:
2267:
2262:
2257:
2252:
2247:
2242:
2237:
2231:
2229:
2228:Key components
2225:
2224:
2222:
2221:
2216:
2211:
2206:
2201:
2196:
2190:
2187:
2186:
2179:
2178:
2171:
2164:
2156:
2147:
2146:
2144:
2143:
2133:
2131:List of people
2128:
2123:
2117:
2114:
2113:
2111:
2110:
2105:
2100:
2095:
2090:
2085:
2080:
2074:
2072:
2068:
2067:
2065:
2064:
2063:
2062:
2052:
2051:
2050:
2043:United Kingdom
2040:
2035:
2030:
2025:
2020:
2015:
2010:
2005:
2000:
1995:
1990:
1985:
1980:
1975:
1970:
1965:
1960:
1955:
1950:
1945:
1940:
1935:
1929:
1927:
1923:
1922:
1920:
1919:
1918:
1917:
1912:
1904:
1903:
1902:
1897:
1892:
1890:Painted turtle
1887:
1882:
1877:
1867:
1866:
1865:
1860:
1859:
1858:
1848:
1843:
1842:
1841:
1831:
1826:
1825:
1824:
1814:
1809:
1807:American bison
1801:
1796:
1795:
1794:
1793:
1792:
1782:
1772:
1766:
1764:
1760:
1759:
1757:
1756:
1751:
1750:
1749:
1739:
1738:
1737:
1727:
1722:
1717:
1711:
1709:
1703:
1702:
1700:
1699:
1694:
1689:
1684:
1678:
1676:
1672:
1671:
1669:
1668:
1663:
1658:
1653:
1648:
1643:
1638:
1633:
1628:
1623:
1618:
1613:
1608:
1602:
1600:
1592:
1591:
1589:
1588:
1583:
1578:
1573:
1568:
1563:
1558:
1553:
1552:
1551:
1546:
1536:
1531:
1526:
1521:
1516:
1511:
1506:
1501:
1496:
1491:
1486:
1481:
1476:
1471:
1465:
1463:
1459:
1458:
1456:
1455:
1450:
1445:
1440:
1435:
1430:
1425:
1420:
1415:
1410:
1405:
1400:
1395:
1390:
1385:
1380:
1375:
1370:
1365:
1360:
1355:
1349:
1347:
1339:
1338:
1336:
1335:
1329:
1326:
1325:
1318:
1317:
1310:
1303:
1295:
1287:
1286:
1277:
1242:
1233:
1196:(1): 334–343.
1176:
1127:
1109:
1072:(4): 317–322.
1049:
1005:
946:
937:
928:
910:
891:(2): 131–140.
875:
865:
808:
807:
805:
802:
792:
770:
767:
733:
730:
724:
718:
703:
697:
691:
682:
679:
675:
674:
662:
656:
653:
650:
646:
642:
639:
636:
633:
629:
624:
617:
614:
610:
605:
600:
597:
594:
590:
585:
578:
575:
571:
566:
563:
559:
554:
550:
545:
541:
521:
515:
500:
496:
484:
483:
468:
464:
460:
457:
453:
449:
446:
441:
437:
417:
402:
398:
386:
385:
370:
366:
362:
359:
355:
351:
348:
343:
339:
322:
316:
307:(in fact, the
303:
297:
292:
289:
282:
276:
274:of inbreeding
264:
257:
251:
237:
228:
222:
216:
210:
204:
187:
174:
168:
162:
155:
142:
136:
130:
125:
122:
112:
102:
86:
83:
61:
58:
49:for fitness).
42:individuals.
15:
9:
6:
4:
3:
2:
2588:
2577:
2574:
2572:
2569:
2567:
2564:
2562:
2559:
2557:
2554:
2552:
2549:
2547:
2544:
2543:
2541:
2526:
2518:
2517:
2514:
2508:
2505:
2503:
2500:
2499:
2497:
2493:
2487:
2484:
2482:
2479:
2477:
2474:
2472:
2469:
2467:
2464:
2462:
2459:
2457:
2454:
2452:
2449:
2447:
2444:
2442:
2439:
2437:
2434:
2432:
2429:
2427:
2424:
2422:
2419:
2417:
2414:
2412:
2409:
2407:
2404:
2402:
2399:
2398:
2396:
2392:
2386:
2383:
2381:
2378:
2376:
2373:
2371:
2368:
2366:
2363:
2361:
2358:
2356:
2353:
2352:
2350:
2347:
2343:
2337:
2334:
2332:
2329:
2327:
2324:
2322:
2319:
2317:
2314:
2312:
2309:
2307:
2304:
2302:
2299:
2297:
2294:
2293:
2291:
2287:
2281:
2278:
2276:
2273:
2271:
2268:
2266:
2263:
2261:
2258:
2256:
2253:
2251:
2248:
2246:
2243:
2241:
2238:
2236:
2233:
2232:
2230:
2226:
2220:
2217:
2215:
2212:
2210:
2207:
2205:
2202:
2200:
2197:
2195:
2192:
2191:
2188:
2184:
2177:
2172:
2170:
2165:
2163:
2158:
2157:
2154:
2142:
2134:
2132:
2129:
2127:
2124:
2122:
2119:
2118:
2115:
2109:
2106:
2104:
2101:
2099:
2096:
2094:
2093:IUCN Red List
2091:
2089:
2086:
2084:
2083:De-extinction
2081:
2079:
2076:
2075:
2073:
2069:
2061:
2058:
2057:
2056:
2055:United States
2053:
2049:
2046:
2045:
2044:
2041:
2039:
2036:
2034:
2031:
2029:
2026:
2024:
2021:
2019:
2016:
2014:
2011:
2009:
2006:
2004:
2001:
1999:
1996:
1994:
1991:
1989:
1986:
1984:
1981:
1979:
1976:
1974:
1971:
1969:
1966:
1964:
1961:
1959:
1956:
1954:
1951:
1949:
1946:
1944:
1941:
1939:
1936:
1934:
1931:
1930:
1928:
1924:
1916:
1913:
1911:
1908:
1907:
1905:
1901:
1898:
1896:
1893:
1891:
1888:
1886:
1883:
1881:
1878:
1876:
1873:
1872:
1871:
1868:
1864:
1861:
1857:
1854:
1853:
1852:
1849:
1847:
1844:
1840:
1837:
1836:
1835:
1832:
1830:
1827:
1823:
1820:
1819:
1818:
1815:
1813:
1810:
1808:
1805:
1804:
1802:
1800:
1797:
1791:
1788:
1787:
1786:
1783:
1781:
1778:
1777:
1776:
1773:
1771:
1768:
1767:
1765:
1761:
1755:
1752:
1748:
1745:
1744:
1743:
1740:
1736:
1735:afforestation
1733:
1732:
1731:
1730:Reforestation
1728:
1726:
1723:
1721:
1718:
1716:
1713:
1712:
1710:
1708:
1704:
1698:
1695:
1693:
1690:
1688:
1685:
1683:
1680:
1679:
1677:
1673:
1667:
1664:
1662:
1659:
1657:
1654:
1652:
1649:
1647:
1644:
1642:
1639:
1637:
1634:
1632:
1629:
1627:
1624:
1622:
1619:
1617:
1614:
1612:
1609:
1607:
1604:
1603:
1601:
1599:
1593:
1587:
1584:
1582:
1579:
1577:
1574:
1572:
1569:
1567:
1564:
1562:
1559:
1557:
1554:
1550:
1547:
1545:
1542:
1541:
1540:
1537:
1535:
1532:
1530:
1527:
1525:
1522:
1520:
1517:
1515:
1512:
1510:
1507:
1505:
1502:
1500:
1497:
1495:
1492:
1490:
1487:
1485:
1482:
1480:
1477:
1475:
1472:
1470:
1467:
1466:
1464:
1460:
1454:
1451:
1449:
1446:
1444:
1441:
1439:
1436:
1434:
1431:
1429:
1426:
1424:
1421:
1419:
1416:
1414:
1411:
1409:
1406:
1404:
1401:
1399:
1396:
1394:
1391:
1389:
1386:
1384:
1381:
1379:
1376:
1374:
1371:
1369:
1366:
1364:
1361:
1359:
1356:
1354:
1351:
1350:
1348:
1346:
1340:
1334:
1331:
1330:
1327:
1323:
1316:
1311:
1309:
1304:
1302:
1297:
1296:
1293:
1281:
1273:
1269:
1265:
1261:
1257:
1253:
1246:
1237:
1229:
1225:
1221:
1217:
1212:
1207:
1203:
1199:
1195:
1191:
1187:
1180:
1172:
1168:
1164:
1160:
1155:
1150:
1146:
1142:
1138:
1131:
1123:
1119:
1118:Darwin, C. R.
1113:
1105:
1101:
1096:
1091:
1087:
1083:
1079:
1075:
1071:
1067:
1063:
1059:
1058:Masel, Joanna
1053:
1045:
1041:
1037:
1033:
1029:
1025:
1021:
1017:
1009:
1001:
997:
992:
987:
982:
977:
973:
969:
965:
961:
957:
950:
941:
932:
924:
917:
915:
906:
902:
898:
894:
890:
886:
879:
869:
861:
857:
852:
847:
843:
839:
835:
831:
827:
820:
818:
816:
814:
809:
801:
797:
787:
783:
781:
775:
766:
764:
760:
756:
752:
748:
747:
742:
741:
729:
715:
687:
678:
660:
654:
651:
648:
644:
640:
637:
634:
631:
627:
622:
615:
612:
608:
603:
598:
595:
592:
588:
583:
576:
573:
569:
564:
561:
557:
552:
548:
543:
539:
531:
530:
529:
526:
498:
494:
466:
462:
458:
455:
451:
447:
444:
439:
435:
427:
426:
425:
422:
400:
396:
368:
364:
360:
357:
353:
349:
346:
341:
337:
329:
328:
327:
312:
310:
288:
272:
247:
245:
233:
201:
196:
194:
193:genetic drift
184:
179:
151:
149:
121:
117:
109:
98:
96:
92:
82:
78:
76:
71:
67:
60:The mechanism
57:
55:
50:
48:
43:
41:
37:
31:
29:
25:
21:
2426:Genetic code
2360:the Americas
2336:Quantitative
2306:Cytogenetics
2301:Conservation
2194:Introduction
1856:Bengal Tiger
1812:Arabian oryx
1803:Land mammal
1790:Golden eagle
1626:Gap analysis
1353:Biodiversity
1343:Conservation
1280:
1255:
1251:
1245:
1236:
1193:
1189:
1179:
1144:
1140:
1130:
1121:
1112:
1069:
1065:
1052:
1019:
1015:
1008:
963:
959:
949:
940:
931:
922:
888:
884:
878:
873:e2110614119.
868:
833:
829:
798:
788:
784:
776:
772:
744:
738:
735:
713:
710:
676:
527:
485:
423:
387:
313:
294:
248:
243:
234:
197:
180:
152:
147:
127:
118:
99:
88:
79:
63:
51:
44:
32:
26:prompted by
19:
18:
2406:Epigenetics
2028:South Sudan
2013:New Zealand
1707:Restoration
763:outcrossing
226:instead of
2540:Categories
2411:Geneticist
2385:South Asia
2331:Population
2311:Ecological
2280:Amino acid
2260:Nucleotide
2235:Chromosome
1963:Costa Rica
1926:By country
1846:Slow loris
1822:Polar bear
1675:Key issues
1462:Approaches
804:References
28:inbreeding
2326:Molecular
2321:Microbial
2296:Classical
2003:Mauritius
1983:Indonesia
1968:Hong Kong
1938:Australia
1910:Seed bank
1900:Sea otter
1770:Arthropod
1742:Rewilding
1596:Protected
1141:Evolution
780:mutations
652:−
635:−
596:−
565:−
459:δ
456:−
361:δ
358:−
2561:Breeding
2525:Category
2451:Heredity
2421:Genomics
2265:Mutation
2255:Heredity
2219:Glossary
2209:Timeline
2183:Genetics
2141:Category
2048:Scotland
2018:Pakistan
1998:Malaysia
1834:Elephant
1763:By taxon
1393:Endemism
1272:18652542
1258:: 1–16.
1228:28421723
1220:18173505
1171:20689054
1163:12583575
1120:(1876).
1104:21888925
1044:11989104
1000:18344325
860:22298709
830:Genetics
91:diploidy
2204:History
2199:Outline
2071:Related
2060:forests
2008:Namibia
1988:Ireland
1973:Iceland
1885:Manatee
1875:Dolphin
1829:Cheetah
1345:biology
1198:Bibcode
1095:3218209
1074:Bibcode
1036:7725789
991:2290798
968:Bibcode
893:Bibcode
851:3316656
759:selfing
755:meiosis
108:neutral
70:fitness
66:diploid
24:alleles
2370:Europe
2355:Africa
2289:Fields
2275:Allele
2250:Genome
2038:Uganda
2033:Sweden
1953:Canada
1948:Brazil
1943:Belize
1933:Angola
1906:Plant
1895:Salmon
1870:Marine
1785:Raptor
1747:marine
1651:Marxan
1270:
1226:
1218:
1169:
1161:
1102:
1092:
1042:
1034:
998:
988:
858:
848:
388:where
317:δ
217:δ
40:inbred
2495:Lists
2375:Italy
2214:Index
1993:Italy
1978:India
1851:Tiger
1799:Fungi
1598:areas
1224:S2CID
1167:S2CID
1040:S2CID
1016:Yeast
271:below
200:model
1863:Wolf
1817:Bear
1775:Bird
1268:PMID
1216:PMID
1159:PMID
1100:PMID
1032:PMID
996:PMID
856:PMID
743:and
2245:RNA
2240:DNA
1260:doi
1206:doi
1149:doi
1090:PMC
1082:doi
1024:doi
986:PMC
976:doi
964:105
901:doi
889:126
846:PMC
838:doi
834:190
260:= 1
195:).
2542::
2348:of
1266:.
1256:42
1254:.
1222:.
1214:.
1204:.
1194:17
1192:.
1188:.
1165:.
1157:.
1145:56
1143:.
1139:.
1098:.
1088:.
1080:.
1070:80
1068:.
1064:.
1038:.
1030:.
1020:10
1018:.
994:.
984:.
974:.
962:.
958:.
913:^
899:.
887:.
854:.
844:.
832:.
828:.
812:^
796:.
262:,
232:.
77:.
30:.
2175:e
2168:t
2161:v
1314:e
1307:t
1300:v
1274:.
1262::
1230:.
1208::
1200::
1173:.
1151::
1106:.
1084::
1076::
1046:.
1026::
1002:.
978::
970::
907:.
903::
895::
862:.
840::
793:g
725:g
719:F
714:N
704:W
698:t
692:W
661:]
655:1
649:t
645:F
641:d
638:2
632:1
628:[
623:]
616:N
613:2
609:1
604:+
599:1
593:t
589:g
584:)
577:N
574:2
570:1
562:1
558:(
553:[
549:=
544:t
540:g
522:d
516:t
499:t
495:g
467:t
463:g
452:e
448:W
445:=
440:t
436:W
418:t
401:t
397:F
369:t
365:F
354:e
350:W
347:=
342:t
338:W
323:t
304:N
298:W
283:g
277:F
265:g
258:F
252:F
244:d
238:g
229:F
223:g
211:g
205:F
188:F
175:f
169:F
163:F
156:F
148:δ
143:F
137:F
131:F
113:g
103:F
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