Počasni srčni utrip dreves

Ponoči, v popolni tišini, so znanstveniki usmerili laserje v vrste dreves in čakali. To, kar so našli, je bilo manj podobno rastlini in bolj speči živali: počasen, enakomeren utrip, ki se vsakih nekaj ur dvigne in spusti ter gre hkrati skozi vse drevo.

At night, in complete stillness, scientists pointed lasers at rows of trees and waited. What they found looked less like a plant and more like a sleeping animal: a slow, steady pulse, rising and falling every few hours, moving through the entire tree at once.

Veje so se ritmično premikale gor in dol za približno centimeter, kot da bi celo drevo nalahno dihalo. Raziskovalci zdaj mislijo, da se deblo samo dejavno stiska in pomaga potiskati vodo navzgor po notranjih ceveh, ki jim pravimo ksilem, namesto da bi se zanašalo le na pasivno vpijanje. Za razliko od človeškega srca, ki utripne kakih sedemdesetkrat ali osemdesetkrat na minuto, lahko utrip drevesa za en sam cikel potrebuje več ur.

Branches shifted up and down by roughly a centimetre, rhythmically, as if the whole tree were gently breathing. Researchers now believe the trunk itself may be actively squeezing, helping push water up through internal tubes called xylem rather than simply relying on passive absorption. Unlike a human heartbeat, which repeats around seventy or eighty times a minute, a tree's pulse can take several hours to complete a single cycle.

Nenavadna misel: vrt, poln dreves, in vsako od njih utripa po svojem zasebnem, izjemno počasnem urniku, popolnoma nevidno, razen če slučajno gledaš v temi s pravim instrumentom.

It is a strange thought: a garden full of trees, each one quietly pulsing on its own private, extremely slow schedule, completely invisible unless you happen to be watching in the dark with the right kind of instrument.