A Wild Earth or a Cloned Zoo? You Decide.
Biology Senior Seminar
November 26, 2003
Stan Grove
Thesis: Cloning endangered species will not be the entire answer for saving them from extinction but only a possible solution to save those that are endangered today.
Outline:
Imagine an earth where every animal lives within an enclosed area where all humankind can see them. Yet, within these enclosures are the only places humans can see these animals alive. Why? It is because the animals' habitats have been damaged and completely destroyed for the needs and usage of human kind. These enclosed areas are called Cloned Zoos: The Final Stronghold of the World's Biodiversity. These cloned zoos are full of cloned animals that have been brought back from the dead or from the edge of extinction. Humankind has come to a point where all life on earth is controlled by human hands and where without the help of humans no animals will survive.
Can you imagine a world where this instance has become reality? Could humankind allow this atrocity to happen? Will they allow this atrocity to happen? Well, some scientists are trying to avert this tragedy from occurring by using cloning to preserve those animals that are endangered or rapidly approaching the brink of extinction. The technology for cloning is improving and some scientists are turning to this technology as a way to preserve the genes of species faced with extinction due to weak reproductive abilities or a population, which is split and unable to reach another population. A member of an endangered species can be cloned and reintroduced into the original or a distant and unreachable population. Another option is the member being cloned can be brought back to life after it has died in order that its genes are still part of the gene pool.
An estimated one hundred species go extinct each and every day, which means that approximately 36,500 species would go extinct every year (British Broadcasting Corporation, 2003). This extinction trend could come to an end one day by the use of cloning technology to preserve and protect endangered species from dying out. Yet cloning is not the final solution because other problems exist and would not be solved by this technology. Therefore, cloning endangered species will not be the entire answer for saving them from extinction but only a possible solution to save those who are endangered today. It is not a complete solution because other factors are involved in the protection of a species and will be discussed later in the paper.
Cloning is a very expensive and time-consuming process that is done in a laboratory. The process also has a very low success rate and requires many eggs and trials to get several live births. John Rennie, the editor for Scientific American magazine, says that "Cloning depends on merging DNA from a body cell into an egg cell stripped of its own DNA, then implanting this composite into a female for gestation," (2000, p. 1). Today scientists are using two differing methods for cloning, the nuclear transfer process and a newer technique called "handmade" cloning.
The nuclear transfer process is the standard technique that has been used by scientists for the majority of cloning procedures. First, the eggs are placed in a culture where they mature. Secondly, a needle is placed into the egg and removes the polar body and genetic material of the egg leaving behind only cytoplasm. Next, the skin cells of the endangered species are grown in a culture. A single skin cell is then pulled up into the needle and inserted in between the zona pellucida [1] and the egg wall. Then, a small electrical shock is administered to the egg and the skin cell and egg fuse together to form a new egg from two different species. Finally, within a few hours after fusion is complete cell division begins (Lanza, Dresser, Damiani, 2000, p. 86-87). This technique produces an egg that is only half the size of the original egg because some of its cytoplasm was removed along with the polar body and nucleus at the beginning of the process.
The other method that is beginning to be used for the cloning process is called handmade cloning because it is much easier to do, less expensive, and more successful. This method was "developed by Gabor Vajta at the Danish Institute of Agricultural Sciences in Tjele together with Ian Lewis, programme leader for the Cooperative Research Centre for Innovative Dairy Products in Australia," (Westphal, 2002, p. 16). Handmade cloning is done by first cutting the egg in half and removing the half that contains the genetic material. Then the other half, called a cytoplast, is fused with a cell from the animal to be cloned. Finally, another cytoplast is fused with this egg to produce a cloned egg of the same proportions as a natural egg (Westphal, 2002, p. 16).
These two processes for cloning differ in several ways; one being the size of the resulting egg is different. Additionally, the second method is cheaper and faster then the first method. Why is the second method cheaper and faster? The equipment needed is inexpensive as is the process, which can be done in either the field or the lab. A Bunsen burner, a very thin blade, and an electofusion machine is required. The machine is the most expensive piece of equipment. The older method must be done within a lab setting because it requires expensive equipment, a micromanipulator for example. The success rate for the nuclear transfer process is twenty five percent of pregnant females at thirty days and the success rate for handmade cloning is a little higher at fifty percent of pregnant females at thirty days (Westphal, 2002, p. 16-17).
Due to the fact that the nuclear transfer process can only be used in the lab, the new method of handmade cloning may be very helpful to scientists who are trying to clone endangered species in the field. Also, because handmade cloning is an inexpensive method, smaller laboratories with smaller budgets can get involved with this science. Although handmade cloning in the field is good, a new problem arises. This is an ethical problem because it asks whether or not it is right to use the females of an endangered species to raise a cloned fetus. Since the cloning process could result in the death of the female decreasing the population and gene pool of the species. This is a problem scientists are trying to avoid. One way scientists can solve this problem is to use "closely related common species" as a source for eggs and surrogate mothers (Westphal, 2002, p. 17). A closely related common species is a species that is genetically similar and has a large, unthreatened population. Another advantage of handmade cloning, "is that it may bypass existing patents" that would regularly block smaller labs from using the nuclear transfer process for cloning (Westphal, 2002, p. 17). Another possible disadvantage of this method is that in the wrong hands the ease of this method would allow a scientist to attempt human cloning (Westphal, 2002, p. 17).
The Idea of Gene BanksÝ (Frozen Zoos):
Our society has a system of blood banks that preserves blood for medical usage when a person needs a blood transfusion. One idea for which scientists are trying to create awareness, are gene banks that are full of the preserved tissues of the world's animals and plants that are endangered. There are already several gene banks running but some scientists want many more to be established (British Broadcasting Corporation, 2003). They would act just like blood banks by allowing the gene pool of a species to be periodically refilled with genes that have disappeared from the existing population. That is, if those genes would have already been stored within a gene bank for preservation.
British scientists have created a gene bank called the Millennium Seed Bank and it is "one of the largest conservation projects ever undertaken," (British Broadcasting Corporation, 2003). This bank has been set up to collect plant seeds and tissue instead of animal tissue. Yet, it is one example of how scientists are working at preserving the tissues of a species so that the possibility of extinction can be averted. Another program being done by British scientists is called the Rare Breeds Survival Trust. This program "is aiming to maintain genetic variation in rare farm animals like the Gloucester Old Spot pig and the Beef Shorthorn cow, by freezing semen and embryos in a vast gene bank," (British Broadcasting Corporation, 2003). This program could also be used for wild species that are endangered and could be a good example of the usefulness of gene banks in helping preserve animals from extinction.
Cloning and gene banks may be a last hope for many species. At this time cloning is not a savior technology, but in the future it may play an important role in helping to keep viable populations of a species alive. Gene banks, with their preserved tissues and genetic material, will help these populations retain a strong gene pool. If the collecting of tissue samples from endangered species does not begin today, when cloning technology is perfected in the future, the chance to save endangered species will have been lost. This is because the "access to declining levels of genetic diversity is more readily available now than in the future," (Ryder, 2002, p. 232). Gene banks could be a supporting player in conservation because the "identification of the [species] at risk and the systematic collection of samples as opportunities arise, consistent with the conservation management of threatened and endangered species, offer increased opportunities for preventing extinction and for the preservation of gene pools," (Ryder, 2002, p. 232). This statement gives the reason for why gene banks are a good idea. A final advantage these banks provide are the benefits future generations would receive from the frozen tissues for research and possibly for cloning (Ryder, 2002, p. 232).
One problem with gene banks is the fact that the preservation of an entire ecosystem is not addressed. Meaning the plants, insects, fungi, bacteria, and animals of the entire ecosystem are not being preserved by these banks. Without all of the species within a habitat, a cloned animal cannot survive in the wild because its' habitat has been completely destroyed and cannot be recreated by human hands. Even with the preservation of every single organism within the habitat the intricacies of the habitat could not be recreated once it is lost. Let alone the difficulty in collecting every single organism when scientists do not even know how many organisms there are in the specified habitat. Therefore any cloned animal would be destined to a life within a zoo.
The Advantages of Cloning Endangered Species:
Cloning has its advantages and its disadvantages for the preservation of endangered species. Some scientists say that cloning will be the best way to preserve endangered species and will provide humans with the means to bring extinct species back from the dead, so even conservation will not be necessary. While other scientists say that cloning will relax the conservation efforts of governments and organizations and be more disastrous then helpful to endangered species. Even other scientists see cloning as a technology, which will be helpful up to a certain point, but regular conservation efforts will still be needed to protect the biodiversity of the earth (Rennie, 2000, p. 1; Coghlan, 2000, p. 5; Ryder, 2002, p. 231-232). The scientists that are worried about conservation efforts being relaxed and the ensuing problems that will occur are focusing on the health of the environment today. They are worried about the habitat destruction that is occurring and where cloned animals will live if their habitat is completely destroyed.
The advantages of cloning are that it helps preserve and propagate a species that has a difficult time reproducing in captivity, for example the Giant panda. Cloning provides scientists with the ability to reintroduce genes into a wild population after they have been lost. It would also free the few remaining females of an endangered species from the risks of pregnancy (British Broadcasting Corporation, 2003, p. 3). It provides the opportunity for species that have gone extinct recently to be cloned and resurrected too. An example of this is the Burcado, a species of mountain goat that lived in Spain. A falling tree killed the final member of the species, a female, and scientists immediately preserved its tissue. In 1999, the genetic material in the preserved tissue was fused with an egg of a subspecies of the Burcado and transferred to a domestic goat for the pregnancy. The pregnancy was successful and produced several kids, but the problem is they are all female because the cloned animal was female. This example stresses the importance of gene banks and how the banks would have been able to help this animal survive (Lanza, Dresser, Damiani, 2000, p. 85, 88). Cloning technology could serve as a "safety net" for future generations too, by allowing future scientists the ability to help endangered species because of having access to their stored genetic material.
Cloning also has disadvantages. It might allow people to see extinction as only temporary and not a big deal. Therefore, the preservation of rare habitats might cease because of a false sense of security accepted by people. Continuing with that idea, some people might see cloning as an easier method for conservation then habitat conservation. This could then lead to a continuation of the damaging way of life human beings live today instead of a change to a way of life where humans and the environment live in harmony (Endangered Species Coalition, 2003). Or it may lead to "the mass cloning of a very few individuals in zoos [which] could reduce the worldwide genetic diversity of a species," (British Broadcasting Corporation, 2003, p. 3). The decrease in genetic diversity could lead to many unforeseen problems. Another possible problem is inbreeding and its effects upon a population."In saluting the wonderful value of cloning as a conservation tool, let's not forget that real conservation involves preserving the life and lands we might least think to save," therefore avoiding a false sense of security (Rennie, 2000, p. 1).
Looking past the advantages and disadvantages of cloning allows an inquisitive person to see the success stories of cloning technology. Endangered animals that have been cloned are the mouflon (wild sheep), the gaur (an oxlike species), the banteng (a wild cattle species), and the burcado mountain goat (extinct at the time of cloning). The unthreatened animals that have been cloned are domestic sheep, mice, cows, goats, pigs, rabbits, cats, mules, horses, rats, and rhesus monkeys. All of these animals required many failed births before they were successfully carried to term and born. For example, when the rat was first successfully cloned to produce Ralph, 129 cloned embryos were implanted into two rats and this resulted in one pregnancy and four live births. Other successes have varied greatly in the amount of eggs used, number of embryos created, pregnancies, and amount of live births (Weise, 2003, p. 1-7). This example shows why cloning is not a simple technology and illustrates that it requires many trials and is very time consuming to have a successful pregnancy that results in a live birth. Thus handmade cloning has brought simple cloning technology nearer to reality (Westphal, 2002, p. 16).
The above-mentioned animals have been cloned using a technique called interspecies embryo transfer. Interspecies embryo transfer is a cloning technique that has been used to clone endangered species and is a process in which "a related, usually domestic, species" provides the needed eggs and is the surrogate mother for the pregnancy (Soma Foundation, 2003). This is the best process for helping endangered species reproduce because it is the least stressful for the animals and the availability of surrogate hosts is plentiful. The only limiting factor is the amount of cells stored in a lab for an endangered species. The animals this technique has been used with, today and probably in the near future, are the endangered animals whose reproductive processes are already well understood (Lanza, Dresser, Damiani, 2000, p. 86).
Advanced Cell Technology (ACT) is the one of the main companies using interspecies embryo transfer and Dr. Robert P. Lanza is one of the main individuals involved in this research. ACT was also the company to facilitate the cloning of the first endangered species using this technique. This company focuses upon cloning domestic animals, like transgenic cows, for medicinal purposes. They clone "animals for use in tissue and cell transplants," and for cloning human stem cells for medicinal purposes (Anderson, 2001, p. 1). ACT recently turned their eye upon cloning endangered species and succeeded when a baby gaur was born from a domestic cow in 2001 (Soma Foundation, 2003).
All attempts with interspecies embryo transfer have resulted in live births and it has been performed upon six endangered species. These species are the African wildcat, the gaur, the Indian desert cat, the bongo antelope, the mouflon sheep, and a rare red deer. The closely related species that have been used as surrogates are domestic cats, sheep, cows, an eland, and "a common white-tailed deer," (Lanza, Dresser, Damiani, 2000, p. 86). Two other species, which scientists desire to use this method upon, are the giant panda and the Asiatic cheetah; which would use black bears and leopards as the surrogate hosts. So far this research is looking very promising. Although there are those who think the money being spent on cloning research for the cheetah is wasteful. "Gajendra Singh, a big-cat expert," questions "the wisdom of bringing back the cheetah when much of the environment where [it] could roam freely has been lost," (McMillan, 2003, p. 5). In this statement Singh has expressed the reasoning behind the idea that the money being spent on rescuing the Asiatic cheetah from extinction is a waste. This is an ethical question that is being asked and answered by scientists today and in upcoming years because this issue will begin to become more important with the continued destruction of the worldís ecosystems.
Another problem with interspecies embryo transfer is that the resulting animals may no longer be a pure species. Instead they may now be a mix of their species DNA and of the surrogate species' DNA. Where would the surrogate species' DNA come from? The mitochondria of the cloned endangered species would not be of its own species' DNA, but of the surrogate's DNA. In addition it is unknown whether or not a common species can raise an endangered species to survive in the wild (McMillan, 2003, p. 2). Nevertheless, an advantage of this technique is it could help bring back extinct species that have intact genetic material stored in a gene bank and have a closely related common species that could be a surrogate (Cloning: Bringing..., 2000, p. 1).
The first endangered species to be cloned using the interspecies embryo transfer technique was a gaur. This baby gaur was born on January 8, 2001, in Iowa and was named Noah. Noah, being the first animal born by the interspecies embryo transfer procedure, opened up "a new day in the conservation of his kind as well as in the preservation of may other endangered species," (Lanza, Dresser, Damiani, 2000, p. 85). Noah lived for only two days and died on January 10, 2001, due to dysentery. Noah's death illustrates that cloning has a long way to go before it can bring live animals into the world with similar problems similar to a natural system (Tobin, 2003, p. 2).
The long path towards an ideal technology for cloning will be a path full of problems needing to be fixed. One problem being faced now is the fitness [2] of cloned animals. For example, in cloned mice "[a]bnormal morphology and lack of developmental success...is associated with abnormal regulation of imprinted genes," (Ryder, 2002, p. 231). Therefore, the question scientists are asking now is not whether the first animal cloned will be healthy but: Whether its descendants will have a good level of fitness or if their genes will be damaged in some way (Ryder, 2002, p. 231)?
Therefore, cloning endangered species will not be the entire answer for saving them from extinction, yet only a possible solution to save those that are endangered today. Cloning is a very helpful technology to have working on the side of conservationist although it still has many problems that must be fixed. There are multiple ways in which cloning can be used to help preserve endangered species including the use of gene banks. Cloning may help preserve those species, which are endangered today but it should not be a process that is relied upon to save all the living creatures upon the earth. It can not be the only process because cloning can not replicate an animal's habitat and every animal needs an environment to live within. Without it they will be confined to a zoo and will always remain captive.
Through the research I have done on this subject I have realized cloning is playing with things humans do not fully understand or ever will. I believe God created this intricate world and we, as humans, will never completely understand it. I think humans are trying to work beyond the limits we were given by God when He created us. These limits are the ability to selectively breed plants and animals to get a desired result but not be able to take genetic material and create with it what we will. Cloning, in my opinion, is messing with creation and it is something God did not intend for humans to do. I feel this technology is going against Christian ethics and morals because God commanded us to be caretakers of His creation and to not destroy it. I perceive cloning as providing people with an excuse to not preserve the environment and that conservation is no longer a necessary act. I see cloning as presenting us with a choice of using it either for good or for evil. I think that Richard T. Wright expresses this well in his book Biology: Through the Eyes of Faith when he says: "We are managers, but not owners. We may put God's property to use. But not misuse. As stewards, we are managers of God's household "for the welfare of the creation and the glory of God," as Earthkeeping records it. So we are to serve the creation and care for it," (1989, p.173).
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[1] The zona pellucida is "the extracellular matrix of the egg," (Campbell, Reece, Mitchell, 1999, p. 940), a protective layer of the egg.
[2] "Fitness is a measure of potential success," (English 107), for a species within a given environment.