I love hippopotamuses. They have the strongest bite force of any mammal, skin so thick that fangs and claws cannot penetrate it, antibacterial sweat, and one of the most terrifying intimidation displays of any animal. Despite looking like a diabetic marshmallow the approximate size and weight of an SUV, hippos can run up to 30 miles per hour (48 kph), faster than the fastest human sprinter. This speed is not reserved for land either—hippos are equally fast in the water due to their incredible density, allowing them to sink and gallop along the bottom of rivers. All things considered, hippos are essentially indestructible killing machines, capable of shrugging off attacks from Africa’s top predators and obliterating them with a bite strong enough to crush cinder blocks. It’s no wonder that hippos kill more humans every year than any other African animal, beating out the likes of lions, hyenas, cobras, and crocodiles.
All that being said, if you were a hippopotamus, spending your days eating river grass, Batista bombing lions, and just generally being a badass, what would make you want to abandon that lifestyle? What evolutionary pressures would drive your offspring to become smaller, more solitary foragers as opposed to grazing behemoths, abandoning much of what makes you so dominant within the ecosystem of African rivers? This might seem like a terrible idea to us humans, but evolution doesn’t have good or bad ideas; animals that are able to reproduce in their environment persist, and those that cannot don’t. Through the process of natural selection, one animal changed the survival strategy of the hippo, abandoning their dominant river niche to become swamp-dwelling nocturnal foragers within the forests of West Africa. Consider: the Pygmy Hippopotamus. Choeropsis liberiensis
These delightful mini-marshmallows have quite a few traits that delineate them from their larger, chunkier cousins. They are, as the name suggests, quite a bit smaller than river hippos, weighing between 350 and 600 pounds (158-272 kg), around the same weight as a domestic pig. That might still seem pretty big, but river hippos usually weigh about 4000 pounds (1800 kg), with the largest specimen ever recorded clocking in at a scale-busting 9900 pounds (4500 kg), over a thousand pounds heavier than the heaviest consumer vehicle in the US. This means that, on average, pygmy hippos are about 1/10th the size of a river hippo. The differences between pygmy and river hippos don’t end at the size, though. Pygmy hippos typically have rounder heads than a river hippo. Their eyes are on the sides of their heads, unlike a river hippo’s, which sit on the top of the head. Pygmy hippos also have longer legs for their body size and less webbing between their toes.
In total, the differences between pygmy hippos and river hippos follow a theme of less reliance on water overall, and this is reflected in pygmy hippo behavior. While river hippos spend most of their time grazing along the bottom of rivers, pygmy hippos actually forage for food on dry land. They eat a variety of vegetation, such as fruit, roots, leaves, and ferns. As they traverse the forest, they do what bears do in the woods, and their shit acts as an excellent fertilizer for the seeds that pass through their digestive systems. By day, pygmy hippos wallow in swamps, where they rest and hide until nightfall returns. This behavior is aided by their natural bobbing reflex, which allows pygmy hippos to sink to the bottom of their swamps and then involuntarily bob to the surface to breathe. While river hippos tend to live in large groups called bloats (I’m serious—that’s what it’s called), pygmy hippos are mainly solitary, never hanging out in groups of more than two. They have a much shier temperament as well, preferring to flee to their swamps than face confrontation. This makes studying pygmy hippos a real pain in the neck, as they are spooked easily and can hide well within their deep forest ecosystems.
Don’t get it twisted, though—pygmy hippos can and will still fuck you up. Pygmy hippos yawn when threatened, revealing a pair of incisor teeth that look like a weapon out of Mortal Kombat. Their bite force clocks in at around 12.4 megapascals (1800 PSI), strong enough to obliterate cinder blocks and turn even the strongest human bone into confetti. Pygmy hippos know how to use these tremendous teeth, too; in 2012, a Czech zookeeper sustained a pygmy hippo bite that landed her in the ICU and nearly required her leg to be amputated. That being said, pygmy hippos have one thing to worry about that river hippos do not: predators. While no predator in its right mind would dare mess with a river hippo, the smaller size and forest habitat of pygmy hippos open them up to attacks by one of Africa’s premier carnivores: the African Leopard. With their incredible strength, ambush tactics, and impressive swimming abilities, leopards are capable of taking down pygmy hippos.
There is, of course, another animal that threatens the pygmy hippo: the human. Pygmy hippos are currently classified as Endangered by the International Union for the Conservation of Nature (IUCN), with a population of fewer than 2500 individuals in the wild. They have been completely driven to extinction in Nigeria, though populations still exist in Liberia, Sierra Leone, Côte D'Ivoire, and Guinea. Deforestation and other forms of land development, such as gold mining, heavily affect the hippos’ habitat. Pygmy hippos are also heavily hunted for their meat by locals, and attempts to put any kind of harvest control into place have failed. Since you’re dying to know, pygmy hippo meat is said to taste similar to beef, but with more fat and gamey undertones. While I would argue that there is nothing inherently wrong with indigenous subsistence hunting, the act may cause the already-tenuous grip conservationists have on wild pygmy hippo populations to slip. Luckily, pygmy hippos are relatively easy to keep in zoos (when I was a kid, the Maryland Zoo in Baltimore had one), but as of yet there have been no attempts to reintroduce them to their natural environment.
A lot of conservation efforts for pygmy hippos have focused on identifying where the hippos live. As they are so shy and sparsely-populated, finding a pygmy hippo’s habitat takes a lot of time and resources. In 2007, the Zoological Society of London, Fauna and Flora International, and the Liberian Forestry Development Authority began a project to identify pygmy hippo habitats across Liberia and develop grassroots conservation efforts to help prevent hunting of the hippo. Since then, the three organizations have succeeded in acquiring some protection for the hippos in various natural parks and wildlife refuges within Liberia and Guinea. Sapo National Park, the oldest and largest protected wildlife area in Liberia, contains a plurality of the pygmy hippos left on Earth, and as such protecting the park has become a major focus for conservation.
Another focus for conservationists has been connecting the largely-disparate wildlife reserves for pygmy hippos in order to increase the species’ biodiversity. When small populations of animals are isolated from each other, populations can become very similar to one another, resulting in them becoming more prone to disease or developing genetic problems due to inbreeding. While Liberia has many conservation areas for pygmy hippos, these areas are not connected to each other, raising concerns that the species’ biodiversity could plummet. You can find a link to donate to Fauna and Flora International’s pygmy hippo conservation project below.
The pygmy hippo is yet another unique and wonderful animal that human activity has driven to the brink of extinction. As one of the only two remaining species of hippopotamus on Earth, losing the pygmy hippo would be a major blow to biodiversity for our planet, removing a creature that cannot be replaced. Furthermore, the hippos are important to their local habitats, helping to distribute seeds through the forests in which they live. Losing these delightful, chunky fellas could cause many other species to decline as well as their seeds become harder to disperse or their food sources vanish. We as a species have the time and resources necessary to save pygmy hippos, but we must now show responsibility for our actions and protect them from extinction.
Sources and More Information:
Video Resources:
Zoos Victoria: Pygmy Hippo Baby Makes a Splash (BABY ALERT: BABY ALERT)
ZSL: Adorable Baby Pygmy Hippo Born (BABY ALERT: BABY ALERT)
コメント