Just some elephant play time from August 2005... ENJOY!
One of the reasons, which I have mentioned before, a decline in carnivore populations can be detrimental to an ecosystem is the spread of disease. Without the proper balance of large wildlife populations (which includes your large carnivores), smaller, disease carrying species (primarily rodents) can overrun an ecosystem causing an increase in disease for local wildlife and humans alike. A study published last week looked at this phenomenon in an area in Africa called the KLEE (the Kenya Long-Term Exclosure Experiment; a well-controlled, replicated large herbivore removal experiment based in central Kenya - an area which includes species such as elephant, giraffe, zebra and lion). Through three years of sampling, this project determined that declines in large wildlife increased the occurrence of landscape-level rodent-borne disease.
The concept is pretty simple (although the analysis from the study is fairly complicated); loss of large wildlife causes a loss in the regulation of the rodent population which, in turn, causes an increase in rodents and their parasite carrying friends, the flea, which increases the amount of disease found in humans and other wildlife. The difficult part is figuring out how to counter this effect (aka prevent disease). The options – prevent the loss of large wildlife so the rodent population can naturally regulate itself or artificially regulate the rodent population. Setting out a few rodent traps out in the middle of the African savannah probably won’t do the trick so, I say, let’s try letting the megafauna do its job and keep working on large wildlife conservation to keep those large wildlife numbers where they should be.
In honor of Jurassic Park opening in 3D today, I thought I would share with everyone the new developments in science which could make this science fiction, science fact. While it will be a LONG time (if ever) until we will be able to clone a T-rex, it is a very real possibility that we will be able to clone more recently extinct animals to create an “insert time period here” park.
Natural decay rates make it impossible to retrieve the whole genome of animals that went extinct tens of millions of years ago but animals that have gone extinct within the past 50,000 years or less could contain enough viable DNA to piece together a fully sequenced genome. The ability to bring back extinct animals is so within reach there was a TEDx conference held in Washington D.C. on March 15th of this year where they discussed the ethics of “De-Extinction.”
After the successful, yet very short lived, cloning of an extinct Ibex in 2003, scientists have been improving and perfecting the process. Now, cloning the megafauna which went extinct during the last ice age is no longer just conjecture. After finding well-preserved mammoths in the Siberian tundra, scientists at the Sooam Biotech Research Foundation in Seoul teamed up with mammoth experts from a university in Siberia to find mammoth tissue buried in the cliffs of the Permafrost. From the bone marrow, hair, skin and fat they found, the scientists are looking for a live cell they can reprogram to grow into an embryo cell then clone. If they can’t find a live, viable cell, their next plan of action is going to be to transfer a mammoth nucleus into an emptied elephant egg cell. But, even if they found a viable cell today, we are still a number of years away from a mammoth being born. After implantation into an elephant surrogate, it would still be 2+ years before any offspring would grace us with its presence (elephant gestation is 645 days).
But, even though the ten year old inside of me thinks this is the COOLEST idea ever, however amazing it would be to see a real, live mammoth, saber-toothed cat or Jefferson’s sloth, what’s the real purpose other than pure entertainment value? There was a reason these species went extinct 10,000 years ago and, while humans may have been a factor and some people may feel “responsible”, we have to remember, it’s been 10,000 years. The ecosystem has had a chance to adapt, change and evolve. Adding those megafauna back into the mix could end up causing more problems than solving. The list of objections and potential conflicts far outweighs the perceived benefits, and this is without adding de-extinction into the equation. But, just because I don’t think a mammoth should be brought back to life, doesn’t mean this research is for not. While I believe it is more important for us as intellectual beings to focus our efforts on pre-extinction than de-extinction, I CAN see the benefits of being able to bring back a species which has recently been wiped off the earth because of human thoughtlessness. Would this research make it possible to see a western black rhino, which was declared extinct only a year and a half ago, on the plains of Africa again? It will be interesting to see where this research takes us in the next decade whether its to a Pleistocene Park or a new population of rhinos in Africa.
A recent study published in the 'Biotropica' journal has revealed that megaherbivores, such as elephants and rhinoceroses, are essential in maintaining the biodiversity of the tropical rainforests of South-East Asia, suggesting they be protected and even reintroduced into areas where have disappeared due to illegal human activity. The megaherbivores’ ability to disperse seeds from the flora they consume far exceeds the abilities of smaller seed-dispersing herbivores, making them an important factor contributing to the structural integrity of the rainforest and the variety found within that type of environment. The tight quarters due to the density of plant species within the rainforest make it difficult for the plants to disperse their seeds themselves so they rely on animals to aide in their dispersal. But plants, such as the mango tree, whose seeds are very large cannot rely on smaller animals to distribute their seeds. Elephants and rhinos are special in that they ingest the whole fruit, seeds and all, and digest them slowly and inefficiently. So, when they poop (it always comes back to poop!), most of the seeds come out and they come out virtually unharmed. This allows them to disperse the seeds across the forests, helping to solve the forest’s own density issue.
The underlying message of the study is to stop illegal hunting. The International Union for Conservation of Nature (IUCN) says that the elephants of South-East Asia are in “danger of extinction” and the two rhinoceros species are “critically endangered”. Elephant and rhino populations world-wide, not just in Asia, are drastically decreasing. The Western Black Rhino of Africa was officially declared extinct on November 10, 2011 with the Northern White Rhino of central Africa “possibly extinct” in the wild and the Javan Rhino in Vietnam “probably extinct” (MSNBC). It is heart wrenching that within the last year we have seen three species of Megafauna go extinct. Every animal has a profound effect on the environment in which they live; otherwise, they wouldn’t have adapted to be there. It’s a shame we have to “discover” why they are important to find it necessary to preserve them.
I am a biologist and my life is crap!