P Barry Tomlinson from National Tropical Botanical Garden, teamed up with graduate student Brett Huggett from Harvard University to explore the idea that palms may be the longest-lived tree, and whether this might be due to genetic underpinnings.
A component of an organism's life span that biologists have been particularly interested in is whether longevity is genetically determined and adaptive.
Researchers emphasise that in many respects, an organisms' life span, or longevity, is determined by the period of time in which its cells remain functionally metabolically active.
They focused on palm trees because they have living cells that may be sustained throughout an individual palm's lifetime, and thus, they argue, may have some of the longest living cells in an organism.
"The difference in potential cell longevity in plants versus animals is a significant point," said Tomlinson.
"It is important to recognise that plants, which are so often neglected in modern biological research, can be informative of basic cell biological features in a way that impacts human concern at a fundamental level," he said
More From This Section
Researchers found that several species of palm have been estimated to live as long as 100 and even up to 740 years.
The important connection here is that while the "skeleton" of the palm may not be as old as a pine, the individual cells in its trunk lived, or were metabolically active, as long as, or longer than those of the pine's.
Palms do not have secondary growth, and there is no addition of secondary vascular tissue. Instead, stem tissues are laid down in a series of interconnected vascular bundles - thus, not only is the base of the palm the oldest and the top the youngest, but these tissues from old to young, from base to top, must also remain active in order to provide support and transport water and nutrients throughout the tree.
Tomlinson and Huggett point out that sieve tubes and their companion cells are examples of cell longevity as they maintain a long-distance transport function without replacement throughout the life of the stem.
Despite several unique characteristics of palms, including the ability to sustain metabolically active cells in the absence of secondary tissues, seemingly indefinitely, unlike conventional trees, in which metabolically active cells are relatively short-lived, the authors do not conclude that the extended life span of palms is genetically determined.
The study was published in the American Journal of Botany.