And if a man prevail against one, two shall withstand him: a threefold cord is not easily broken.”
Ecclesiastes 4:12, Douay-Rheims
Let us now leave the Kingdoms of the Archaea and of Bacteria and visit two more with many residents that we cannot see with the unaided eye: the Kingdom of the Protists and the Kingdom of Fungi. Like the Kingdoms of the Archaea and of Bacteria, the protists and fungi are full of surprises; unlike the two tiny kingdoms, we can see many of the latter creatures if we search the woods and fields around the world. Probably the strangest kingdom of all, though, is that of the protists.
If something is not an animal, not a plant, not a fungus, not a bacteria, and not an archaea, then it is a protist. This might sound obvious, but it is in fact how scientists decide what belongs in this kingdom! It is like grouping together chocolate chip cookies, a hamburger, and iced tea because they are not Italian, Mexican, or Chinese food. Of course these three foods have very little in common, but if the only remaining option is “Other foods” then they would have to be grouped together.
Flying over the Kingdom of the Protists, you would see much empty-looking soil and water, home to many thriving protists. You would also see oceans filled with towering green spires and fallen logs that are covered with disturbingly bright-colored goop. Some of these protists are plant-like, such as the red algae that sometimes covers the ocean or the giant kelp forests that provide habitat for many ocean species. Others are more animal-like, such as microscopic amoebas that can shift and transform their shape and a deep-sea dwelling creature (a xenophyophorea, if you are brave) that has only one cell but is as large a cereal bowl! There are even some that are fungus-like, such as the brightly colored goop on the logs known as slime mold. This richness of diversity certainly makes the Kingdom of Protists one of the most surprising and intriguing of the Kingdoms of Creation.
Visiting the Kingdom of Fungi brings us back into more familiar territory. Flying overhead, you would see fallen logs and tree stumps, old apples and dried leaves, all covered with gray or green or white fuzziness, or perhaps some white or red or orange mushrooms. Those mushrooms are what we usually think of when we think of fungus, although among the 75,000 known species of fungi, only about 12,000 are mushrooms. Mushrooms appear very similar to plants in that they are stationary and grow in similar environments, but unlike like plants, fungi do not produce their own food. Fungi eat other things, and are one of the chief decomposers in many environments, breaking down dead living things so that new living things can take their place.
There is no denying that mushrooms are intriguing: a delicious pizza topping, a dangerous forest dweller, a tree stairway to the sky. These little creatures seem to pop up out of nowhere and are gone again in just a few days, so it might surprise you to learn that potentially the largest creature in the entire world is a mushroom. This mushroom lives in Oregon, covers over 2000 acres mostly underground (an area two and half times as large as Central Park in New York City), and likely weighs at least 10,000 tons (or as much as about 65 blue whales). Scientists think that this mushroom is not only enormous but also ancient – maybe even growing when the pyramids were being built in Egypt.
Mushrooms come in an astonishing variety. Many mushrooms look like the typical white miniature umbrellas, but others are like shelves coming out of trees or branches reaching for the sky or balls that explode in a cloud of dust when you touch them; they can be yellow, red, or orange and have evocative names like chicken of the woods or cauliflower mushrooms or lion’s mane mushrooms. Many species of mushrooms are grown for us to eat, but others are extremely dangerous, so never eat a mushroom that you find – mushrooms are as beautiful and diverse as they can be dangerous.
In the Kingdom of the Fungi, there are also several types of creatures that are just one cell – yeasts, molds, and mildews. Yeasts have been our great help in the kitchen from the dawn of history, making breads light and fluffy and helping to make other foods, including the savory British spread known as Marmite. Molds and mildews are somewhat less appetizing, such as when they are making fuzzy colonies on our old bread or fruit, doing the important work of decomposition. Molds come in various colors, such as black, red, and blue, while mildews are all white.
Before we leave these two kingdoms, we must visit a creature that is neither here nor there, so to speak. It is a nomad that roams among the kingdoms: the lichen. Lichens grow on trees or rocks, looking kind of like flat leaves or short green branches or even orange dust. These creatures are made up of a fungus and a bacteria or an algae (a kind of protist) living together as one creature. The two working together are stronger than each on its own, allowing them to live in harsh environments like the Arctic and in deserts: the protist or bacteria will make food for the fungus, and the fungus provides water and offers protection. These little creatures are surely a wonder of creation.