On the Idea of Resurrecting Extinct Species

 

The famous "Life finds a Way" quote from Jurassic Park, quoted by Ian Malcolm, played by Jeff Goldbum

(from giphy.com)

When we hear about the idea of resurrecting extinct species, we tend to think of ethic issues and dilemmas that science-fiction books and movies depict. The most popular of these is “Jurassic Park”, the novel by Michael Crichton and the movie by Steven Spielberg, along with the new "Jurassic World" film coming up. Some of these questions asked include “Should we do it?”, “Are we playing God?”, “Is it the right thing to do?”, “Would anything we bring back cause any environmental issues?” etc. Additionally, we would respond to the idea of cloning extinct species as impossible since most scientists claim that ancient DNA is mostly degraded and would not be viable for biological functions. This was true initially, but in the last few years, remarkable breakthroughs have been achieved in science, making the possibility of resurrecting extinct species more feasible by the day. There has already been one great example of an extinct species of ibex (a Pyrenean ibex, or Capra pyrenaica pyrenaica) being cloned (Folch, 2009). There is even a program being run by a group of scientists who are determined to clone species of animals that have died recently. These include the dodo (Raphus cucullatus) and the thylacine (Thylacinus cynocephalus). This group would relocate them back to their original habitats (Heidari, 2013). Therefore, it appears that whether we like it or not, the possibility of resurrecting extinct species is increasing and we may not be able to avoid facing the ethical issues.

Picture and Brief Description of Smilodon Fatalis (wiki)

The question I am asking is not whether cloning species is possible or going to happen, but what would the REAL pros and cons be of cloning extinct species. One hypothetical situation we could review in researching this would be to study the effects of a resurrected ancient species of predator, which was introduced to an island to control a non-native population of modern-day herbivores. The resurrected ancient predator I am referring to would be a saber-toothed cat (Smilodon fatalis or 'Deadly Knife-Tooth') or, sometimes incorrectly called a saber-toothed tiger. This big cat is a specialized predator that hunted in packs that stalked the North American continent during the last Ice Age (over 1 million to 10,000 years ago), hunting only the large game that roamed the continent at the time. These included bison, mammoths, ground sloths, wild horses, etc. Many species of saber-toothed cats are large in size, but this one is about the same size and weight as a modern African lion (Panthera leo), reaching up to 40 inches height at the point of shoulder and weighing in between 300 to 620 lbs. However, the saber-toothed cat is more heavily built than the average lion. Thanks to its bulky build, short-tail, and fore-arms longer than its hind legs, it became an ambush predator, as it was not built for speed (Meachen-Samuels, 2012). In order to stalk its prey, it needs bushes and forest area. The big cat is best known for its two iconic 7 inch long upper canine teeth that the saber-tooth uses to swiftly kill its prey via crushing the windpipe and cutting up major blood vessels and arteries. Ironically, due to their length and narrowness, these canines are actually quite fragile. Due to this, the big cat cannot bite into bone and can only eat the fleshier parts of the carcass, leaving the rest to other scavengers and young cubs (Therrien, 2005). This feeding style means that it couldn’t eat a rabbit, let alone a human. It is theorized that the saber-tooth died out as a combination of climate change, habitat change, and a decrease in big game population. The best sources of DNA that could be used for recreation would be from specimens of the La Brea tar pits of Los Angeles, California (Janczewski, 1992).

The island in question is the Santa Catalina Island, located 22 miles of the coast of Los Angeles, California. The island is about 75 square miles in size and while somewhat populated and a common tourist and recreation area, most of the island is owned by the Catalina Island Conservancy. The island is home of some species of plants and animals

endemic to the area that are found nowhere else in the United States or the world. These species include island fox (Urocyon littoralis), Santa Catalina Island harvest mouse (Reithrodontomys megalotis catalinae), Ornate shrew (Sorex ornatus), Catalina Island ironwood (Lyonothamnus floribundus ssp. floribundus), etc. But, these populations have been threatened by non-native species, such as goats, pigs, cats, etc. While several of these non-natives have been eradicated from the island, there are some of them still residing on the island.


Right: Santa Catalina Island (wiki)

A herd of Bison on Santa Catalina Island (from katherinebelarmino.com)

One such species is a herd of American bison or buffalo (Bison bison), the prey species of the saber-toothed cat. The bison were said to be introduced there by a film production crew in 1924, though this is debated (Lidicker, 1991). Regardless, since their origin on the island, their population has been growing unchecked for decades, from the original 14 or 24 in the 1920s to around 400 individual bison around 1970. At present, as a result of culling, roundups, shipping, and birth control, the population is currently around 150-200 bison (Sweitzer, 2005). That population, according to research, is near the maximum 300 head the island can support, due to its low precipitation. The kind of ecological damage that the bison have caused to the island includes destruction of riparian areas and plant communities, spread of invasive plants (Constible, 2005), overgrazing, and soil erosion. The bison are still present on the island due to the fact that the locals like them, they are important for tourism, and control the amount of wildfire fuel (dry plants) on the island.

So, what happens when a small pack of saber-toothed cats have been introduced to Santa Catalina Island to hunt the buffalo? What are the pros and cons?

Believe it or not, there are actual pros associated with introducing saber-toothed cats in this situation. One such pro is that a small pack of saber-tooth cats can easily keep the population of bison in check without spending time and money on roundups and birth control. The saber-toothed cats would control the population by taking down a bison once or twice every week. We can verify this by researching and understanding the hunting patterns of lions and other big cats. Also, since saber-tooth cats are ambush predators, they would only hunt bison in forested areas and in riparian areas. These are the areas that bison are causing ecological damage to. With the threat of being pounced upon in those areas apparent, the bison will only visit these areas for only a short period of time; just long enough to get the amount of water needed, which will minimize any sort of damage to those certain areas. Also, the effects of introducing predators would have other positive effects on their behavior. One of which is that they will graze more closely to each other (Grandin) and this would control the distribution of wildfire fuel more effectively, while minimizing the continued eco-damage and creating an environment for more rapid recovery of these areas. We know this to be true by observing the effects of reintroduced wolves to Yellowstone National Park.

When not having fish, bald eagles prefer to have carrion

The predation of the saber-tooth will also benefit the native species as well. With the reintroduction of bald eagles (Haliaeetus leucocephalus) happening currently on the island (Garcelon, 1988), the eagles seem to have some issues recovering from their local extinction. As mentioned earlier, saber-tooth cats only consume the fleshier part of their kills and leave the rest to the elements and scavengers. On the mainland, the carrion is a big part of the bald eagles’ diet during certain parts of the year (Mersmann, 1992). With the saber-tooth cats leaving excess meat all over the island, the eagles can use this as an alternative food source during times of food scarcity. This may also be an exceptional food source for the island foxes, though this is not as certain.

Along with being an ecological benefit to the island, this proposal could also be an economic benefit to the inhabitants as well. In Africa, tourists from all over the world come to see the many beautiful animals there, with big cats being among the most popular and desired. In this situation, it is not different, but it has a twist. The twist is where else on earth would you get to see saber-toothed cats resurrected and in the wild? Tourists will no doubt pay to go to Santa Catalina Island, not just to enjoy the sunshine and bison, but to experience their own “Jurassic Park”-ish tour (from a safe distance or in the safety of a tour bus, of course).

While this situation would have considerable pros, it also would have quite a few cons, as well. One of which is that while the saber-toothed cats would definitely control the bison population, the saber-toothed cat population would have to be controlled by humans. In African models, you would need about 200 horse-sized prey items or more to support one lion pride its life time (Schaller). As mentioned earlier, Santa Catalina Island cannot support more than 300 bison on the whole island (at least the parts that the bison are free to roam on). With this in mind, we would have to either sterilize the cats, birth control them, or annually take any new cubs from their mother and put them into captivity.

Also, there is the issue of the cats possibly preying on domestic livestock. But this issue is pretty low on the list of concerns because there are no longer any cattle operations on the island, as the island's conservation group has relocated all cattle and other livestock to the mainland. The only livestock that is of concern are horses, which natives and tourists use to ride around the island on. Since isotopic analysis has confirmed that saber-toothed cats have hunted horses during their reign, this is a concern. And this leads to the next concern: possible predation on humans.

As mentioned earlier, it is unlikely that saber-toothed cats would view humans as a potential food source, since they are more designed for big animals and humans are too small. But there are two factors that would still make it a concern, all the same. One is that paleontological evidence has shown that young saber-toothed cats’ fangs are smaller than those of a fully grown adult and can eat carcasses and prey items that adult cats would find to bony for them to eat. And, in modern big cats, it is usually the younger individuals that become potential man-eaters, so reason would indicate that this would be the same for the saber-toothed cats. The second factor is that as with modern big cats, saber-toothed cats could go after prey even if they were not hungry. Like a lot of predators, big cats can be motivated to hunt something due to sudden movements (Mysterud, 1980). A basic example would be your dog chasing a car. There have been cases that illustrate a leopard going after another object of prey, even though it has just killed one prey. This is stimulated by the second object of prey’s movement. So, a jogger, mountain biker, or a running hiker would probably trigger the prey response in the saber-tooth and a dangerous and fatal encounter could occur.

Like with cougars, Smilodon's hunting instinct could be triggered by the bicyclists' movements
(Los Angeles Times)

There are three things that could be done to avoid such encounters. One would be to educate the tourists and community about these big cats and all the tips about how to avoid these cats or how to act around them. Another would be to place tracers in all the saber-toothed cats. Since there would be a small controlled number, this should be practical. The second would be to develop a hand-held (or belt/wrist held for bikers and joggers) device that tourists would rent and have so it would warn them that they are close to a saber-tooth, maybe 50-100 yards away. The final one would be to give each tourist a can of pepper spray or other deterrent, in case of an unavoidable attack.

So what did we learn from this discussion and what is our conclusion? My conclusion is that resurrecting any extinct species would have both a balance of good and bad consequences, as with most real life situations. While resurrecting species should not be feared as it often is, it should be taken very seriously and must be monitored and regulated. Of primary importance is to regulate which extinct species should be allowed in cloning experiments and a well thought out and researched plan for the future of the cloned species so that “Jurassic Park” situations are not created.

And, what is the moral or ethical issue here? The real issue with this sort of project or anything else like it is not whether we are playing God or whether we should we do it, but if we do bring species back from extinction, we should only do it if there is an ecosystem the species could release to without causing an ecological disturbance. The species would be brought back not just to live in a zoo but become a sort of "trophy" species, and would have some sort of practical value to us and the present day ecosystems. For example, the thylacine or Tasmanian tiger has been wiped out only just recently. The last one died in a Tasmanian zoo in 1936, and the niche or top predator in its native habitat is still open. If the thylacine was brought back to life, grew in numbers and genetic diversity, and was reintroduced to the wilds of Tasmania, it would have a profound effect on the ecosystem. Some possibilities would be the regulation of several native and non-native prey species and provide a more readily supply of carrion for its smaller, scavenging cousin, the Tasmanian devil (Sarcophilus harrisii).

What are my feelings about the idea of cloning extinct species? Well, for one part, I've been interested in the idea ever since I've watched "Jurassic Park" when I was a wee lad. In fact, that movie and idea was what had set me into my current major: Animal Science. And for another part, it scared me at the time. As a Christian, I used to have conflicts about that idea of cloning extinct species, worrying that we may be playing God and should not do this to creation. That was until these questions came up in my mind: Did we play God when we wiped out species, did we play God when we selectively bred our livestock for our uses, did we play God when we shaped the land to make our cities and crops, did we play God when we created the atomic bomb, did we play God when we developed artificial insemination, etc?

Along with those questions, one book I have read that has actually convinced me that all of this is okay, as long as we're responsible and smart about out decisions, is the Bible itself. As I've read and studied the Bible, I've come to learn that since God has given us the abilities to have some dominion over creation, we are able to do things that nature would not do on its own. With this power, we have destroyed nature in several ways, but we have used this power to heal nature as well. So, I now see the power to clone extinct species not as a defiling act against God but as a tool that God has given us help heal this hurt planet and to help ourselves in the process.

References

-Constible, J. M., et al. "Dispersal of non-native plants by introduced bison in an island ecosystem." Biological Invasions 7.4 (2005): 699-709.

-Folch, J., et al. "First birth of an animal from an extinct subspecies (< i> Capra pyrenaica pyrenaica</i>) by cloning." Theriogenology 71.6 (2009): 1026-1034.

-Garcelon, David K. The reintroduction of bald eagles on Santa Catalina Island, California. Diss. Humboldt State University, 1988.

-Grandin, Temple, and Catherine Johnson. Animals make us human: Creating the best life for animals. Houghton Mifflin Harcourt, 2009.

-Heidari, Nader. "Reviving The Dead." CHEMICAL & ENGINEERING NEWS 91.14 (2013): 34-34.

-Janczewski, Dianne N., et al. "Molecular phylogenetic inference from saber-toothed cat fossils of Rancho La Brea." Proceedings of the National Academy of Sciences 89.20 (1992): 9769-9773.

-Lidicker, W. Z. "Introduced mammals in California." Biogeography of Mediterranean Invasions. Cambridge University Press, Cambridge (1991): 263-271.

-Meachen-Samuels, Julie A. "Morphological convergence of the prey-killing arsenal of sabertooth predators." Paleobiology 38.1 (2012): 1-14.

-Mersmann, Timothy J., et al. "Assessing bias in studies of bald eagle food habits." The Journal of wildlife management (1992): 73-78.

-Mysterud, Ivar. "Bear management and sheep husbandry in Norway, with a discussion of predatory behavior significant for evaluation of livestock losses." Bears: Their Biology and Management (1980): 233-241.

-Schaller, George B. The Serengeti lion: a study of predator-prey relations. University of Chicago Press, 2009.

-Sweitzer, RICK A., et al. "History, habitat use and management of bison on Catalina Island, California." 6th California Islands Symposium, Institute for Wildlife Studies, Ventura, CA. 2005.

-Therrien, Francois. "Feeding behaviour and bite force of sabretoothed predators." Zoological Journal of the Linnean Society 145.3 (2005): 393-426.

-Valkenburgh, B., Mark F. Teaford, and Alan Walker. "Molar microwear and diet in large carnivores: inferences concerning diet in the sabretooth cat, Smilodon fatalis." Journal of Zoology 222.2 (1990): 319-340.