A few age ago , a radical of researchers made a strange uncovering : No matter where they are on Earth , Cook true pine tree diagram lean toward the equator .
Cook pines ( Araucaria columnaris ) have a clear-cut inclination to them . In fact , according to the researchers that discovered the equatorial skimpy , " when grown alfresco of its native range , this species has a pronounced lean so ubiquitous that it is often used as the identify characteristic for the coinage . "
Matt Ritter , now director at Cal Poly Plant Conservatory , was writing about the pines for a book when he notice that the trees he had studied all seemed to tip to the south , New Scientistreported . Ritter began echo co-worker around the world to see which way their cook pines were leaning , and shortly found that they all seemed to be leaning toward the equator .
Ritter and his team quantify 256 trees across five continents on a chain of mountains of latitudes to try the phenomenon further .
" We evidence that the Cook pine ’ lean is non - random : trees in the Northern Hemisphere skimpy south , and those in the Southern Hemisphere skimpy north , " the team write in their study . " Additionally , the magnitude of the lean is more pronounced at higher latitudes in both hemisphere . "
On mediocre , the Sir Herbert Beerbohm Tree lean 8.05 degree toward the equator , but the leans were more pronounced further out from the equator , and only 9 per centum of tree move off from the portend focusing .
Usually , trees grow vertically in response to the contradict influences of gravity ( gravitropism ) and light ( phototropism ) .
" The leading hypothesis for the molecular mechanism of gravitropism is that alluviation of amyloplasts on actin microfilaments trip a sign transduction nerve pathway resulting in asymmetric transport of auxin in the stem , causing it to straighten itself parallel with the gravity vector , " the bailiwick authors compose .
In more competitive or challenging environments , tree may grow in other directions , as they raise toward the useable light . While immature plant life may grow toward the Sun , however , they tend to correct themselves as they develop due to the influence of gravity . It ’s not readable why cook pine have their classifiable lean , though the team suggest it could be an unhelpful , non - adaptive quirk of their genetics or something else .
" The mechanisms underlying directional lean ofAraucaria columnarismay be relate to an adaptative tropic response to the relative incidence angles of annual sunlight , gravity , magnetism , or any combination of these , " the team concludes .
" It is interesting that the pronounce lean inA. columnarisis rarefied in other species , including otherAraucarianative to New Caledonia . It is possible that the biophysical restraint of leaning for a tall tree ultimately prevail over any benefits of additional light interception gained by leaning . "
The squad adds that the phenomenon call for more report , as the " plants are responding to their global environment in a way not yet full empathise . "
The study is published inEcology .
