Two holobionts enjoying each other's company. Sara peacefully sleeps in the "arms" of a beech tree on the Amiata mountain. She is obviously happy to be embraced in this way; we are tempted to think that the tree thinks the same.
Do trees perceive the world around them? Absolutely yes, but in a very different way from how we humans do. Trees have no eyes, no muscles, no above-ground nerves. But they perceive chemical signals, light signals, vibrations, and, probably, things that we don't even imagine could be perceived. So, the tree gently holding Sara cannot "see" her. But it can perceive her presence in the form of vibrations and chemical signals. The tree perceives Sara more or less how we could perceive a ghost.
And what does the tree think of Sara? The brain of the tree is below ground; it is the vast network of connections of the root system, boosted by the help of fungi. It is called the mycorrhizal system. Maybe this alien brain can form an image of the strange creature resting near its trunk, although, for us, it is nearly impossible to understand in which form. Maybe the tree is asleep, too. And what does it dream? We can't know, just as we can't know what Sara is dreaming. The only thing we can say is that there is no reason to think that holobionts can't be in love with each other.
h/t Sara
