The higher death rate of the female striped maple will put the number of trees in these populations into decline over the long-run.
Striped maple trees (acer pensylvanicum ) change sex from year to year, researchers - who conducted a study published in the journal Annals of Botany, Rutgers University-New Brunswick - found.
The study showed that some 54% of the striped maple trees changed sexes over a four-year period, with some carrying out the process at least twice. This adaptation, according to the scientists, aids the longevity of the striped maple plant.
Understory trees, like the striped maple, grow beneath the forest canopy and can become less healthy because of they are more vulnerable to animals and adverse environmental factors, which could have prompted the plant to switch sex in a bid to survive.
One other understory plant, the Jack-in-the-pulpit, also switches sex.
As a result, males flowers outnumber female trees, three to one. Since the study started in 2014, approximately 75% of trees that died were female.
https://t.co/HVU4uJSAc7 Striped maple trees can change sex from year to year, and male trees grow more but female trees are more likely to die. Study finds that 54% of striped maple trees changed sexes over a 4-year period, with some switching at least twice. Male trees usually… pic.twitter.com/b0BYYeXj6Q
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"We found that, contrary to previous scientific knowledge, unhealthy trees have a higher likelihood of being female, and the size of the tree doesn't seem to influence what sex a tree is," lead author and Princeton botanist Jennifer Blake-Mahmud, explained.
The higher death rate of the female striped maple will put the number of trees in these populations into decline over the long-run.
More than 90 percent of flowering plant species combine both sexes in one plant, while in the less than 10% of plant species where female and male flowers exist separately, the plant retains its gender for a lifetime.
The scientists are investigating the cause of the rare phenomenon in the striped maple, specifically sugar concentration levels, loss of branches or other environmental factors, to determines if they vary by the sex of the plant.