Parasites In Your Ecosystem
Guest post by Jerry C. Hinn, MS Zoology
Have you considered whether or not your species gets worms? Because parasites are interested in your species. Humans have textbooks full of parasites who either accidentally end up in us and cause harm, or purposefully seek us out as their preferred host. Parasitism is a strategy a surprisingly diverse group of earth animals engage in, for either part or all of their life cycle, and whether you steal a blood meal and fly off, lay your eggs in the nest of a host species for them to raise, or live inside their digestive system and feed on your “share” of the bounty, you can show up right next to an apex predator and say “hey buddy, can me and a hundred of my friends have a word with you?”
Of all the animal phyla on earth, the only ones who do not have examples of parasites in their ranks are simple filter feeders and chordates... but if you count brood parasites like cuckoos, then it just goes down to the filter feeders. Even clams, who are filter feeders, spend part of their lives as parasites clamping down on fish gills and feeding on blood and secretions from them. There are butterflies who are parasites that feed on tears and blood from large mammals who can’t get them off their faces. Sure, leeches, ticks, hookworms and liver flukes are all sexy examples of parasites who depend entirely on the lifestyle, but they are hardly the only ones.
Even parasites get parasites. This is called hyperparasitism, and one of earth’s best examples is Wolbachia bacteria. These bacteria are parasites of insects, but are much more easily passed to other insects when laid in eggs. Male insects can get Wolbachia but don’t pass it along to their children. So, the bacteria has a little solution to that slight problem: Infected insects don’t produce sons. The bacteria interferes with their reproductive system and in some cases selectively offs eggs that are male so that mom puts more energy laying eggs that are plump and full of daughters. Which in turn spreads the bacteria to another group of females who do the same. The reason this is interesting is because mosquitoes have these parasites, too. Imagine the possibility of wiping out every single male mosquito on the planet so that there’s nobody left to fertilize eggs?
Perhaps your species IS a parasite. Now we don’t have to worry about farming our own food or even raising our own young. Don’t be shy. When the world provides you with all you need, its your right, nay, your duty, to spread as many infectious eggs into the environment as you can. After all, you can’t be asked to leave a warm comfy gut lining and face the harsh elements like some... free living mongrel. Better you make ten thousand eggs and a few of them find their way into a host than for you to die fruitlessly tending them. After all, it isn’t as if you’re struggling to get nutrition to make those eggs, what with the boundless generosity of your host. Why, if you didn’t take your share, it would really be a waste, wouldn’t it?
One last thought: Drinking milk from a species that you are not might technically be parasitism. That cow didn’t make the milk for you, it made it because it had a calf, and mammals nurse their young. That we continue to stimulate the cow to make milk long after its calf weaned is, in a real way, stealing nutrients from the cow to feed to us without killing and eating the cow. What if instead of milking animals, we kept herd animals around to feed on their blood? If your species evolved from blood feeding parasite ancestors, perhaps that’s exactly what they would do!
Title image by Erik Karits from Pexels and used with their kind permission.