Humans share a closer branch with fungi than with plants
The surprising answer is fungi: humans are more closely related to mushrooms than to trees or flowers. That does not mean people descended from mushrooms. It means the animal and fungal branches of life split from each other more recently than either split from the plant branch.
What “closely related” means on the tree of life
Evolutionary relationships are measured by shared ancestry, not by how much two living organisms look alike. Humans and mushrooms both belong to a broad group of cells whose nuclei hold their DNA. Within that group, animals and fungi are evolutionary neighbors: their lineages trace back to a shared ancestor that lived after the lineage leading to plants had already branched away.
Over time, descendants of that ancient ancestor changed in very different directions. One lineage gave rise to animals, including humans; another produced fungi, including mushrooms. Plants followed a separate path. The common ancestor was not a modern mushroom, human, or plant, but an ancient organism from which those distinct lineages eventually developed.
Why the relationship is easy to miss
A mushroom seems nothing like a person, while plants are familiar and share visible features with us, such as growing on land. But resemblance is a poor guide to evolutionary kinship. Fungi absorb nutrients from their surroundings, while animals take in food and digest it inside their bodies; plants capture light to make sugars. Those differences reflect long, separate histories—not a closer relationship between people and plants.
So the next time a mushroom appears in the woods, the useful comparison is not “a strange plant.” On the evolutionary family tree, fungi occupy a branch closer to ours.
