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another edit to another page http://en.wikipedia.org/wiki/Small_population_size Examples of genetic consequences that have happened in inbred populations are bone abnormalities, low infant survivability, and decrease in birth rates. Some populations that have these consequences are cheetahs, who suffer with low infant survivability and a decrease in birth rates due to having gone through a population bottleneck. Northern elephant seals, who also went through a population bottleneck, have had cranial bone structure changes to the lower mandibular tooth row. Then the wolves on Isle Royale, a population restricted to the island in Lake Superior have bone malformations in the vertebral column in the lumbosacral region. These wolves also have syndactyly, which is the fusion of soft tissue between the toes of the front feet. These types of malformations are caused by inbreeding depression or genetic load. [1]

edits http://en.wikipedia.org/wiki/Inbreeding Malformations or harmful traits can stay within a population due to a high homozygosity rate and it will cause a population to become fixed for certain traits, like having too many bones in an area, like the vertebral column in wolves on Isle Royale or having cranial abnormalities in Northern elephant seals, where their cranial bone length in the lower mandibular tooth row has changed. Having a high homozygosity rate is bad for a population because it will unmask recessive deleterious alleles generated by mutations, reduce heterozygote advantage, and it is detrimental to the survival of small, endangered animal populations [10]. When there are deleterious recessive alleles in a population it can cause inbreeding depression. The authors think that it is possible that the severity of inbreeding depression can be diminished if natural selection can purge such alleles from populations during inbreeding [11]. If inbreeding depression can be diminished by natural selection than some traits, harmful or not, can be reduced and change the future outlook on a small, endangered populations.

FINAL DRAFT STARTS HERE! Sometimes in small populations inbreeding is inevitable. Inbreeding occurs when related family members, like aunt and nephew or mom and son, breed with each other and produce offspring and the offspring reproduce with other family members. There are populations that have gone through a population bottleneck reducing their numbers drastically, like cheetahs and northern elephant seals. Disease has also affected some populations and so has overhunting, which is the reason the northern elephant seal went through a population bottleneck. Population bottleneck occurs when there has been an environmental catastrophe for example an earthquake, tornado, flood, etc. and reduces the population so there are only a few surviving organisms left of that species. Founder effect is another possibility for inbreeding, a new, small population with no similar species around. Founder effect can also happen when species are introduced to new areas, like an island. A downside to founder effect is it reduces the genetic variation in a population. There are genetic consequences however to inbreeding, such as decrease in birth rates, low infant survivability, bone structure abnormalities, and low genetic diversity. Inbreeding also causes the loss of genes in a population, which in return could make a population go from being heterozygotes to homozygotes in the Hardy-Weinburg Equation. When there is a low genetic frequency there is a higher chance that genes will be lost in the earlier generations (Hill 1979). When there is a small population that means there are not many different genes to be passed around the population causing low frequency. Examples of these consequences will be given in more detail later. Inbreeding is related to evolution because genetic consequences start to occur after several generations. These genes are passed on generation to generation; some of the genes will show negative aspects of inbreeding, like wrongly shaped hips or vertebra. When inbreeding occurs there is a chance that inbreeding depression will occur. If inbreeding depression does occur then there is a reduction of fitness in a population, such as a decrease in reproductive output and a decrease of survivability. (Szulkin, et al. 2013). Inbreeding depression can cause an animal to become lame therefore increasing its chance to become prey and reduce its aspects of reproducing and spreading its genes onto the next generation. There are three examples that will be described that have had genetic consequences due to inbreeding. Many years ago the cheetah went through a population bottleneck reducing the population drastically. Now most of the cheetahs are inbred and there are no new genes to be brought into the population. Because of the generations of inbreeding, cheetahs have dealt with low infant survivability and a decrease in birth rates. Some causes of juvenile mortality, which is considered death of cubs to be under six months of age, are stillbirth, neonatal problems, and congenital problems (Wielebnowski 1996). With no new genes coming in the outlook for an improvement of birth rates and survivability is low. Northern elephant seals are the second example. In the 1800s the seals were hunted for their blubber, which was used for oil to heat homes and as a light source. The seals went through population bottleneck when the population went from hundreds to 10-20 individuals due to overhunting. Because the seals are inbred they have had cranial structure changes. The cranial changes were the length of the lower mandibular tooth row. It showed significantly greater fluctuating asymmetry in modern elephant seals compared to southern elephant seals (Hoelzel, 1999). A third example is wolves that live on Isle Royale in Lake Superior. Low gene flow on the island has caused genetic consequences in the bone structure of this population. The only way for wolves to be introduced to the island is by human intervention or for the winter to get so cold that the lake freezes and the wolves can walk on the ice. The last time the lake froze a new wolf was introduced to the population bringing new genes. The bone structure problem that these wolves have is in their vertebral column. There have been incidences where wolf skeletons were studied and there were more vertebrae than there is supposed to be. There are also congenital malformations in the lumbosacral region and cases of syndactyly, which is the fusion of soft tissue between the toes of the front feet. These types of malformations are caused by inbreeding depression or genetic load. Genetic load is the reduced fitness in small, isolated populations (Raikkonen, 2009). These malformations or harmful traits can stay within a population due to a high homozygosity rate and it will cause a population to become fixed for certain traits, like having too many bones in an area or having cranial abnormalities. Having a high homozygosity rate is bad for a population because it will unmask recessive deleterious alleles generated by mutations, reduce heterozygote advantage, and it is detrimental to the survival of small, endangered animal populations (Meagher 2000). When there are deleterious recessive alleles in a population it can cause inbreeding depression. The authors think that it is possible that the severity of inbreeding depression can be diminished if natural selection can purge such alleles from populations during inbreeding (Swindell 2006). If inbreeding depression can be diminished by natural selection than some traits, harmful or not, can be reduced and change the future outlook on a small, endangered populations. There are ways to help reduce inbreeding in both the wild and captive populations. One is by keeping studbooks so zoos and other conservation centers will have access to an animal’s genetic records and keep form breeding animals with close family members. Inbreeding can be minimized in social mammal populations by a direct result of behaviors that promote active avoidance of incestuous mating or as an indirect outcome of sex-biased dispersal (Storz, et al. 2001). Some of these behaviors can be a result of a pair of mates staying together for life and not going mate to mate every breeding season. Inbreeding has been reduced in captive breeding and manipulation of productivity of animals in the wild by a program for the conservation of the bird, Mauritius Kestrel. In this program the Mauritius Kestrel were introduced to a new area and their genes would be new genes for the population that was already living there. (Ewing, et al. 2008). So by introducing new genes to a population it decreases the likelihood of inbreeding. One study that involved Takahe, a bird in New Zealand, was moved by scientists to different islands so they can be introduced to new populations and different genes can be spread throughout the population. This was done so it would avoid close inbreeding in an island population (Jamieson, et al. 2003). A population on an island has a low gene flow because of being separated from the mainland where there is an abundance of genes. The abundance of genes has no way to get to the islands without human interference or the birds have enough strength to fly out to the islands. Another way inbreeding can be reduced is by educating the people. If they know what is going on they might be able to help, maybe not in a big way but a little help can go a long way. Although some inbreeding is inevitable for some populations it can be avoided in some. Prevention is always important. Keeping animals alive and not on the threatened or endangered species list is a start to help keep from inbreeding, but that is not always possible. There will always be something or someone that affects the population in one way or another. Population bottleneck that has affected so many species will keep happening especially with the growing population of humans, the need to survive, and the changing environment. Genetic consequences of inbreeding still needs to be studied and material needs to be learned. There are many consequences that populations are dealing with and humans are deciding whether it is better by intervening by introducing new animals to an area so new genes can be spread or taking an inbred population and spreading them out so they will stop breeding with each other causing more complications. Complications that are happening within the populations are low birth survivability, low fecundity, cranial malformations, and bone deformities. Multiple things need to be done but there are still many things that are unknown to people and how to stop inbreeding or at least reduce the effects may take time.

References Ewing, S, et al., 2008. Inbreeding and Loss of Genetic Variation in a Reintroduced Population of Mauritius Kestrel. Conservation Biology. 22: 395-404. Hill, G, William. 1979. Genetic and Phenotypic Consequences of Inbreeding. Journal of Toxicology and Environmental Health. 5: 27-42. Hoelzel A. Russell. 1999. Impact of Population Bottlenecks on Genetic Variation and the Importance of Life-History; A Case Study of the Northern Elephant Seal. Biological Journal of the Linnean Society. 68: 23-39. Jamieson, I. et al. 2003. Sex-Specific Consequences of Recent Inbreeding in an Ancestrally Inbred Population of New Zealand Takahe. Conservation Biology. 55: 708-716. Meagher, Shawn. Et al. 2000. Male–male competition magnifies inbreeding depression in wild 	house mice. PNAS. 97: 3324-3329. Raikkonen, J. et al. 2009. Congenital Bone Deformities and the Inbred Wolves (Canis lupus) of Isle Royale. Biological Conservation. 142: 1025-1031. Stroz, J. et al. 2001. Genetic Consequences of Polygyny and Social Structure in an Indian Fruit Bat, Cynopterus Sphinx. Inbreeding, Outbreeding, and Population Subdivision. Evolution. 55: 1215-1223 Swindell, William R. et al. 2006. Selection and Inbreeding Depression: Effects of Inbreeding 	Rate and Inbreeding Environment. Evolution. 60: 1014-1022 Szulkin, M, et al. 2013. Inbreeding Avoidance, Tolerance, or Preference in Animals? Trends in Ecology and Evolution. 28: 205-211. Wielebnowski, Nadja. 1996. Reassessing the Relationship between Juvenile Mortality and Genetic Monomorphism in Captive Cheetahs. Zoo Biology. 15: 353-369.

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Bumblebees Less Successful to 'Ineffiecient' Males. (2009). BioMed Central Limited. Retrieved September 14,2014, from http://www.sciencedaily.com/releases/2009/07/090701190414.htm this article tells how bumblebees can be affected by inbreeding. with the population of bumblebees already decreasing the fear of inbreeding may become a problem Cnokrak, P.,& Roff,D.A. (1999). Inbreeding Depression in the Wild. Heredity, 260-270. doi:10.10381sj.hdy.6885530 this article describes how inbreeding is a direct consequence causing inbreeding depression. it talks about captive versus wild and the number of inbred animals

Ellstrand, N.C., & Elam, D.R. (1993). Population Genetic Consequences of Small Population Size: Implications for Plant Conservation. Annual Review of Ecology and Systematics, 24, 217-242. Retrieved September 14.2014, from http://www.jstor.org/stable/2097178 this article dives into helping plants who are in need of help against inbreeding. explains how inbreeding can affect a population

Lee, J.J. (2014, August 20). Can Artifical Insemination Save Endangered Species? Retrieved September 14,201, from http://newswatch.nationalgeographic.com/2014/08/20/can-artificial-insemination-save-endangered-species/ this article informs readers taht artificial insemination may be able to help against inbreeding by freezing sperm and eggs and use them for future use. can lead to mre genetically diverse populations in the future.

Species Conservation Poised to Benefit from DNA Advances. (2014, February 24). Retrieved September 14,2014, from http://wwww.sciencedaily.com/releases/2014/02/140224171328.htm this article writes about how genetic family trees can help reduce the number of inbred animals by having the DNA of populations on record

http://en.wikipedia.org/wiki/inbreeding Artificial insemination (AI) has been helping farmers with their animals in where they can select what kind of offspring they want produced. I wonder how this can help with inbreeding by collecting different samples and then freeze them and use them when a population may be getting inbred so new genes can be introduced and then a whole population won't be affected. AI could possible help with animals that are becoming endangered or threatened and have samples in a lab that could be used to help endangered animals from being inbred.

http://en.wikipedia.org/wiki/bottleneck Cheetahs are one of the most famously known animals that have gone through a populaton bottleneck that reduced their population dramatically, because of that reduction, most if not all cheetahs are inbred. Inbred meaning that they reproduce with relatives. For the cheetah population cousins, sisters, uncles, etc. are the only ones left to mate with. A consequence of inbreeding is no new genes are being introduced into the population and could cause genetic problems like low survival rate and infertility.

http://en.wikipedia.org/wiki/conservation_biology There are probably many ways in which scientists and medicine can help endangered species. one way that could possibly help is artificial insemination. it is known, especially on farms where a farmer choses what kind of offspring they would like and chose a sperm donor to inseminate a female with. what if today's animals had sperm collected and froze, so that it can be used in the future. that may help in reducing the amount of animals that have a chance of becoming inbred.

Wielebnowski, N. (1996). Reassessing the Relationship Between Juvenile Mortality and Genetic Monomorphism in Captive Cheetahs. Zoo Biology, 15(4), 353-369. doi: 10.1002/(SICI)1098-2361(1996)15:43.0.CO;2-A (one source and one sentence added to wikipedia page) added to inbreeding page Cheetahs are another example of inbreeding. Thousands of years ago the cheetahs went through a population bottleneck that reduced their population considerably so the animals alive today area ll related to one another. A consequence from inbreeding for this species has been high juvenile mortality, low fecudity, and poor breeding success.