Carnivorous Respiration

Kohric and I sat beneath the breathing tree for a long while before my lesson began. The slow, bellows-like sound the tree makes is soothing in a way I’m not sure I can describe. If you close your eyes, you can almost imagine you’re hearing the planet itself breathing; and that if you could just center yourself a bit more you could feel its very heartbeat. It’s a restful experience. I can imagine wise old gurus twisting themselves up into pretzels and meditating under this kind of tree.

I was feeling better than I had in weeks. You don’t always notice that you’re under stress or constantly nervous until you get a respite. Then suddenly you feel like you’re expanding after having been squashed for so long. The longer I’d been feeling out of sorts, the less I’d tried to learn about the Azu-nah and Minervan ecology. I impulsively decided to remedy that immediately, and asked Kohric out of the blue why a tree, a plant, would need to breathe at all.

“To eat,” he said.

“To… eat?” I asked, and stared over at the tree in confusion. Kohric seemed to find this highly amusing. The guy is cryptic just to mess with me. I know it! But instead of answering me, he got up and put his hand beside one of the fist-sized openings in the trunk. I followed him, and as I approached he began pointing.

“Here,” he said, gesturing to a thin, shiny strip of clear goo sitting in the base of the opening, “smells of food for small creatures. They fly here. They come close or go inside.” The tree took a “breath” and I could see the glop shiver as air was drawn into the tree. “Tree breathes in, and creatures are caught inside,” Kohric said, “They are trapped.”

Without warning he grabbed my wrist and shoved my fingers up into the opening. For a horrible second I could feel tiny, cold, slimy little nub-like things wiggled along my fingertips. It was like I’d stuck my hand into a nest of baby octopuses, or teeny sea anemones. I jerked my hand back and flapped my wrist in disgust, sending globules of sticky mucus flying.

Ugh!

Kohric found this even funnier than my earlier confusion. I flicked mucus at him.

“Inside here,” he said, returning to his pointing, “are many small... mouths.” He gestured for me to look inside. My image of sea anemones wasn’t that far off; tiny polyps, almost like corals, lined the inside of the opening. I could even see a few tiny animals caught amongst them. It was gross, but I was too fascinated to care.

The tree made its breathing sound again, and this time no air moved in or out of the opening we stood by. I turned to Kohric. “It does not breathe out?” I asked.

He pointed up into the tree’s branches. “Breath comes out up in the leaves.” He gestured to a low-hanging branch, and I could see the leaves rustle. Tiny holes on the underside of the branch above were blowing air down and across the lower leaves.

I was absolutely fascinated; so much so that I immediately pulled my computer pad out and attempted to puzzle out a cross-section. Kohric watched from over my shoulder and explained it to me as I went. He was actually incredibly knowledgeable about the internal structure of this thing. I have no idea where he’d have learned it.

Anyway, here’s what we ended up with: The tree “inhales,” pulling air (and unlucky organisms) into its feeding tubules. Tiny coral-like polyps trap and digest the captured prey. I’m assuming this provides the tree with an otherwise rare/limited nutrient, like a Venus fly trap catches insects to get nitrogen in poor soil.

Once inhaled, the air travels into a large chamber near the base of the trunk. This structure is surrounded by some kind of flexible, muscle-like mass that can expand and contract.


When the plant needs to exhale, the mass expands, drastically shrinking the air chamber, and forces air up into the branches. Tiny air holes on the bottoms of the branches release the air. According to Kohric, there are tiny flaps (just like the epiglottis in the human trachea) that are forced shut against the feeding tubes, so that air only goes out through the upper branch holes. And similar flaps keep air from being inhaled from the branches, so maximum force is applied to trapping food in the feeding tubes.

The feeding tubes are obvious in their structure. But the odd branch openings are more of a puzzle. I do have a hypothesis, though. Now, this is just an assumption of course, but if this tree uses CO₂ (or some other type of gas) to synthesize sugars like Earth plants, then having a way to circulate air over the leaves would significantly increase its growth. It’s the same type of principle that makes Earth plants grow better if you talk to them or play music next to them. The sound waves circulate air, allowing the plant better gas exchange. Except this tree may do it itself.

I love science!