The changing climate has caused shifts in habitats and increase in species interaction and hybridization. Climate change is a widely debated topic, but the science is undeniable, and the consequences sometimes unforeseen. Hybridization is one of these unpredicted consequences that could lead to an even more rapid extinction of endangered species. One of the most pronounced cases is with the polar bear in the Arctic. With the Arctic shrinking and the tundra expanding, grizzly and polar bears are now interacting more, and mating. Which does not sound like too big of a deal, however, with their dwindling numbers, it will only increase the rate at which polar bears disappear from the wild.
Hybridization is not a new phenomenon, in fact, humans themselves are a product of interspecies breeding. Have you ever wondered why you don’t see Neanderthals walking through the streets of Houston? Because humans out-competed Neanderthals nearly 60,000 years ago. Many modern humans of European or Asian descent still have a small amount of Neanderthal DNA. It was not only Neanderthals though. Modern humans interbred with several subspecies such as Homo Erectus and Homo Habilis. Modern Homo Sapiens were the outcome of all this interbreeding.
This is not a singular phenomenon either, it is what slowly shaped the species we see across the globe today. However, climate change is speeding up this process. In particular, with the bears. This may not seem to be an issue, as it has been happening since the beginning of life on earth, but it could pose some problems moving forward. Since the Artic is shrinking, polar bears will get the short end of the stick in this situation. The hybrids will be more likely to roam in Grizzly territory, because it will be much larger due to the warming climate, therefore mating with other grizzlies. This will take all of these opportunities for polar bears to reproduce, cutting short their already dwindling numbers. Paired with the melting of their habitat, oil exploration, toxic pollution and over hunting, the likelihood of polar bear numbers making a comeback is less likely.
The issue comes not only with the loss of individual species, but an overall decrease in global biodiversity. Each species holds a specific niche in their ecosystem. If one species is lost, then their role is vacated and all that they add to their ecosystem lost. For example, if polar bears go extinct, then the population of their prey will sky-rocket. Seals, sea lions, and other populations will grow out of control with nothing limiting the growth rate. This will cause fish population to drastically decline because the large population of seals will have to have a food source. With the wide variety of fish population being close to the base of the chain, it will affect every species that depends on them for food. That decreases the overall stability of the ecosystem.
This is happening all across the wild. Coyotes and wolves are interbreeding in North America. Warming water temperatures in Montana are increasing interaction between different species of trout. Golden-winged warblers and blue-winged warblers are starting to hybridize. Bobcats and lynx in Minnesota are also mingling. The list goes on and on. It is not always bad though. With the case of the Heliconius butterflies in the Amazon, it is proving to be beneficial. They are interbreeding with other butterflies passing on a trait that causes their wings to be brightly colored, showing predators they contain cyanide. So, only time will tell what hybridization does to the overall health of our planet.
The best way to solve this problem, and preserve our planet’s precious biodiversity, is to slow climate change. As a nation, our focus in energy needs to shift away from fossil fuels and towards a source that releases fewer carbon emissions, whether this comes in the form of renewables like solar wind and hydro, or nuclear power. Scientists are also making great progress in the research of biofuels. All of these alternatives will greatly reduce the effect of carbon on climate change. With a new administration in the white house, who seem to ignore the facts of climate change, it is up to the younger generations to bring the issue to the front lines of political debate. Scientifically, we are far and beyond the days of global warming denial. As a society, we must come together to the realization that this is a true science, and work towards a solution.
The human race has come a long way in understanding the world around us, yet we still have a long way to go. Earth is the only example of a planet with life that we have ever seen. We have no other example to compare ourselves to. We really are not sure where we fit in nature, but we are learning. We cannot predict the future or what it holds, but we can use the evidence to predict what the outcome might be. And we cannot ignore the signs that our planet is in peril. If action is not taken soon, it may be too late.